OpenShift Container Platform 3.3

Installation and Configuration

OpenShift Container Platform 3.3 Installation and Configuration

Red Hat OpenShift Documentation Team

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Abstract

OpenShift Installation and Configuration topics cover the basics of installing and configuring OpenShift in your environment. Use these topics for the one-time tasks required to get OpenShift up and running.

Chapter 1. Overview

OpenShift Container Platform Installation and Configuration topics cover the basics of installing and configuring OpenShift Container Platform in your environment. Configuration, management, and logging are also covered. Use these topics for the one-time tasks required quickly set up your OpenShift Container Platform environment and configure it based on your organizational needs.

For day to day cluster administrator tasks, see Cluster Administration.

Chapter 2. Installing a Cluster

Planning

Initial Planning

For production environments, several factors influence installation. Consider the following questions as you read through the documentation:

Which installation method do you want to use? The Installation Methods section provides some information about the quick and advanced installation methods.

How many hosts do you require in the cluster? The Environment Scenarios section provides multiple examples of Single Master and Multiple Master configurations.

How many pods are required in your cluster? The Sizing Considerations section provides limits for nodes and pods so you can calculate how large your environment needs to be.

Is high availability required? High availability is recommended for fault tolerance. In this situation, you might aim to use the Multiple Masters Using Native HA example as a basis for your environment.

Which installation type do you want to use: RPM or containerized? Both installations provide a working OpenShift Container Platform environment, but you might have a preference for a particular method of installing, managing, and updating your services.

Installation Methods

Both the quick and advanced installations methods are supported for development and production environments. If you want to quickly get OpenShift Container Platform up and running to try out for the first time, use the quick installer and let the interactive CLI guide you through the configuration options relevant to your environment.

For the most control over your cluster’s configuration, you can use the advanced installation method. This method is particularly suited if you are already familiar with Ansible. However, following along with the OpenShift Container Platform documentation should equip you with enough information to reliably deploy your cluster and continue to manage its configuration post-deployment using the provided Ansible playbooks directly.

If you install initially using the quick installer, you can always further tweak your cluster’s configuration and adjust the number of hosts in the cluster using the same installer tool. If you wanted to later switch to using the advanced method, you can create an inventory file for your configuration and carry on that way.

Sizing Considerations

Determine how many nodes and pods you require for your OpenShift Container Platform cluster. Cluster scalability correlates to the number of pods in a cluster environment. That number influences the other numbers in your setup.

The following table provides the maximum sizing limits for nodes and pods:

Type
Maximum

Maximum nodes per cluster

1000

Maximum pods per cluster

120,000

Maximum pods per node

250

Maximum pods per core

10

Important

Oversubscribing the physical resources on a node affects resource guarantees the Kubernetes scheduler makes during pod placement. Learn what measures you can take to avoid memory swapping.

Determine how many pods are expected to fit per node:

Maximum Pods per Cluster / Expected Pods per Node = Total Number of Nodes

Example Scenario

If you want to scope your cluster for 2200 pods per cluster, you would need at least 9 nodes, assuming that there are 250 maximum pods per node:

2200 / 250 = 8.8

If you increase the number of nodes to 20, then the pod distribution changes to 110 pods per node:

2200 / 20 = 110

Environment Scenarios

This section outlines different examples of scenarios for your OpenShift Container Platform environment. Use these scenarios as a basis for planning your own OpenShift Container Platform cluster.

Note

Moving from a single master cluster to multiple masters after installation is not supported.

Single Master and Multiple Nodes

The following table describes an example environment for a single master (with embedded etcd) and two nodes:

Host Name
Infrastructure Component to Install

master.example.com

Master and node

node1.example.com

Node

node2.example.com

Single Master, Multiple etcd, and Multiple Nodes

The following table describes an example environment for a single master, three etcd hosts, and two nodes:

Host Name
Infrastructure Component to Install

master.example.com

Master and node

etcd1.example.com

etcd

etcd2.example.com

etcd3.example.com

node1.example.com

Node

node2.example.com

Note

When specifying multiple etcd hosts, external etcd is installed and configured. Clustering of OpenShift Container Platform’s embedded etcd is not supported.

Multiple Masters Using Native HA

The following describes an example environment for three masters, one HAProxy load balancer, three etcd hosts, and two nodes using the native HA method:

Host Name
Infrastructure Component to Install

master1.example.com

Master (clustered using native HA) and node

master2.example.com

master3.example.com

lb.example.com

HAProxy to load balance API master endpoints

etcd1.example.com

etcd

etcd2.example.com

etcd3.example.com

node1.example.com

Node

node2.example.com

Note

When specifying multiple etcd hosts, external etcd is installed and configured. Clustering of OpenShift Container Platform’s embedded etcd is not supported.

Stand-alone Registry

You can also install OpenShift Container Platform to act as a stand-alone registry using the OpenShift Container Platform’s integrated registry. See Installing a Stand-alone Registry for details on this scenario.

RPM vs Containerized

An RPM installation installs all services through package management and configures services to run within the same user space, while a containerized installation configures installs services using container images and runs separate services in individual containers.

The default method for installing OpenShift Container Platform on Red Hat Enterprise Linux (RHEL) uses RPMs. Alternatively, you can use the containerized method, which deploys containerized OpenShift Container Platform master and node components. When targeting a RHEL Atomic Host system, the containerized method is the only available option, and is automatically selected for you based on the detection of the /run/ostree-booted file.

The following table outlines the differences between the RPM and Containerized methods:

Type
RPM
Containerized

Installation Method

Packages via yum

Container images via docker

Service Management

systemd

docker and systemd units

Operating System

Red Hat Enterprise Linux

Red Hat Enterprise Linux or Red Hat Atomic Host

The Containerized Installation Preparation section provides more details on configuring your installation to use containerized services.

Prerequisites

System Requirements

The following sections identify the hardware specifications and system-level requirements of all hosts within your OpenShift Container Platform environment.

Red Hat Subscriptions

You must have an active OpenShift Container Platform subscription on your Red Hat account to proceed. If you do not, contact your sales representative for more information.

Important

OpenShift Container Platform 3.3 requires Docker 1.10.

Minimum Hardware Requirements

The system requirements vary per host type:

Masters

Physical or virtual system, or an instance running on a public or private IaaS.

Base OS: RHEL 7.1 or later with "Minimal" installation option, or RHEL Atomic Host 7.2.6 or later.

2 vCPU.

Minimum 16 GB RAM.

Minimum 40 GB hard disk space for the file system containing /var/.

Nodes

Physical or virtual system, or an instance running on a public or private IaaS.

Base OS: RHEL 7.1 or later with "Minimal" installation option, or RHEL Atomic Host 7.2.6 or later.

NetworkManager 1.0 or later

1 vCPU.

Minimum 8 GB RAM.

Minimum 15 GB hard disk space for the file system containing /var/.

An additional minimum 15 GB unallocated space to be used for Docker’s storage back end; see Configuring Docker Storage.

External etcd Nodes

Minimum 20 GB hard disk space for etcd data.

Important

OpenShift Container Platform only supports servers with x86_64 architecture.

Note

Meeting the /var/ file system sizing requirements in RHEL Atomic Host requires making changes to the default configuration. See Managing Storage in Red Hat Enterprise Linux Atomic Host for instructions on configuring this during or after installation.

Production Level Hardware Requirements

Test or sample environments function with the minimum requirements. For production environments, the following recommendations apply:

Master Hosts

In a highly available OpenShift Container Platform cluster with external etcd, a master host should have 1 CPU core and 1.5 GB of memory, on top of the defaults in the table above, for each 1000 pods. Therefore, the recommended size of master host in an OpenShift Container Platform cluster of 2000 pods would be 2 CPU cores and 5 GB of RAM, in addition to the minimum requirements for a master host of 2 CPU cores and 8 GB of RAM.

When planning an environment with multiple masters, a minimum of three etcd hosts as well as a load-balancer between the master hosts, is required.

The OpenShift Container Platform master caches deserialized versions of resources aggressively to ease CPU load. However, in smaller clusters of less than 1000 pods, this cache can waste a lot of memory for negligible CPU load reduction. The default cache size is 50000 entries, which, depending on the size of your resources, can grow to occupy 1 to 2 GB of memory. This cache size can be reduced using the following setting the in master-config.yaml:

kubernetesMasterConfig:
  apiServerArguments:
    deserialization-cache-size:
    - "1000"

Node Hosts

The size of a node host depends on the expected size of its workload. As an OpenShift Container Platform cluster administrator, you will need to calculate the expected workload, then add about 10 per cent for overhead. For production environments, allocate enough resources so that node host failure does not affect your maximum capacity.

Use the above with the following table to plan the maximum loads for nodes and pods:

Host
Sizing Recommendation

Maximum nodes per cluster

1000

Maximum pods per cluster

120000

Maximum pods per nodes

250

Maximum pods per core

10

Important

Oversubscribing the physical resources on a node affects resource guarantees the Kubernetes scheduler makes during pod placement. Learn what measures you can take to avoid memory swapping.

Configuring Core Usage

By default, OpenShift Container Platform masters and nodes use all available cores in the system they run on. You can choose the number of cores you want OpenShift Container Platform to use by setting the GOMAXPROCS environment variable.

For example, run the following before starting the server to make OpenShift Container Platform only run on one core:

# export GOMAXPROCS=1

SELinux

Security-Enhanced Linux (SELinux) must be enabled on all of the servers before installing OpenShift Container Platform or the installer will fail. Also, configure SELINUXTYPE=targeted in the /etc/selinux/config file:

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=enforcing
# SELINUXTYPE= can take one of these three values:
#     targeted - Targeted processes are protected,
#     minimum - Modification of targeted policy. Only selected processes are protected.
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

Security Warning

OpenShift Container Platform runs containers on your hosts, and in some cases, such as build operations and the registry service, it does so using privileged containers. Furthermore, those containers access your host’s Docker daemon and perform docker build and docker push operations. As such, you should be aware of the inherent security risks associated with performing docker run operations on arbitrary images as they effectively have root access.

For more information, see these articles:

http://opensource.com/business/14/7/docker-security-selinux

https://docs.docker.com/engine/security/security/

To address these risks, OpenShift Container Platform uses security context constraints that control the actions that pods can perform and what it has the ability to access.

Environment Requirements

The following section defines the requirements of the environment containing your OpenShift Container Platform configuration. This includes networking considerations and access to external services, such as Git repository access, storage, and cloud infrastructure providers.

DNS

OpenShift Container Platform requires a fully functional DNS server in the environment. This is ideally a separate host running DNS software and can provide name resolution to hosts and containers running on the platform.

Important

Adding entries into the /etc/hosts file on each host is not enough. This file is not copied into containers running on the platform.

Key components of OpenShift Container Platform run themselves inside of containers and use the following process for name resolution:

By default, containers receive their DNS configuration file (/etc/resolv.conf) from their host.

OpenShift Container Platform then inserts one DNS value into the pods (above the node’s nameserver values). That value is defined in the /etc/origin/node/node-config.yaml file by the dnsIP parameter, which by default is set to the address of the host node because the host is using dnsmasq.

If the dnsIP parameter is omitted from the node-config.yaml file, then the value defaults to the kubernetes service IP, which is the first nameserver in the pod’s /etc/resolv.conf file.

As of OpenShift Container Platform 3.2, dnsmasq is automatically configured on all masters and nodes. The pods use the nodes as their DNS, and the nodes forward the requests. By default, dnsmasq is configured on the nodes to listen on port 53, therefore the nodes cannot run any other type of DNS application.

Note

Previously, in OpenShift Container Platform 3.1, a DNS server could not be installed on a master node, because it ran its own internal DNS server. Now, with master nodes using dnsmasq, SkyDNS is now configured to listen on port 8053 so that dnsmasq can run on the masters. Note that these DNS changes (dnsmasq configured on nodes and the SkyDNS port change) only apply to new installations of OpenShift Container Platform 3.2. Clusters upgraded to OpenShift Container Platform 3.2 from a previous version do not currently have these changes applied during the upgrade process.

Note

NetworkManager is required on the nodes in order to populate dnsmasq with the DNS IP addresses.

The following is an example set of DNS records for the Single Master and Multiple Nodes scenario:

master    A   10.64.33.100
node1     A   10.64.33.101
node2     A   10.64.33.102

If you do not have a properly functioning DNS environment, you could experience failure with:

Product installation via the reference Ansible-based scripts

Deployment of the infrastructure containers (registry, routers)

Access to the OpenShift Container Platform web console, because it is not accessible via IP address alone

Configuring Hosts to Use DNS

Make sure each host in your environment is configured to resolve hostnames from your DNS server. The configuration for hosts' DNS resolution depend on whether DHCP is enabled. If DHCP is:

Disabled, then configure your network interface to be static, and add DNS nameservers to NetworkManager.

Enabled, then the NetworkManager dispatch script automatically configures DNS based on the DHCP configuration. Optionally, you can add a value to dnsIP in the node-config.yaml file to prepend the pod’s resolv.conf file. The second nameserver is then defined by the host’s first nameserver. By default, this will be the IP address of the node host.

Note

For most configurations, do not set the openshift_dns_ip option during the advanced installation of OpenShift Container Platform (using Ansible), because this option overrides the default IP address set by dnsIP.

Instead, allow the installer to configure each node to use dnsmasq and forward requests to SkyDNS or the external DNS provider. If you do set the openshift_dns_ip option, then it should be set either with a DNS IP that queries SkyDNS first, or to the SkyDNS service or endpoint IP (the Kubernetes service IP).

To properly check that hosts are correctly configured to resolved to your DNS server:

Check the contents of /etc/resolv.conf:

$ cat /etc/resolv.conf
# Generated by NetworkManager
search example.com
nameserver 10.64.33.1
# nameserver updated by /etc/NetworkManager/dispatcher.d/99-origin-dns.sh

In this example, 10.64.33.1 is the address of our DNS server.

Test the DNS servers listed in /etc/resolv.conf are able to resolve to the addresses of all the masters and nodes in your OpenShift Container Platform environment:

$ dig <node_hostname> @<IP_address> +short

For example:

$ dig master.example.com @10.64.33.1 +short
10.64.33.100
$ dig node1.example.com @10.64.33.1 +short
10.64.33.101

Disabling dnsmasq

If you want to disable dnsmasq (for example, if your /etc/resolv.conf is managed by a configuration tool other than NetworkManager), then set openshift_use_dnsmasq to false in the Ansible playbook.

However, certain containers do not properly move to the next nameserver when the first issues SERVFAIL. Red Hat Enterprise Linux (RHEL)-based containers do not suffer from this, but certain versions of uclibc and musl do.

Configuring a DNS Wildcard

Optionally, configure a wildcard for the router to use, so that you do not need to update your DNS configuration when new routes are added.

A wildcard for a DNS zone must ultimately resolve to the IP address of the OpenShift Container Platform router.

For example, create a wildcard DNS entry for cloudapps that has a low time-to-live value (TTL) and points to the public IP address of the host where the router will be deployed:

*.cloudapps.example.com. 300 IN  A 192.168.133.2

In almost all cases, when referencing VMs you must use host names, and the host names that you use must match the output of the hostname -f command on each node.

Warning

In your /etc/resolv.conf file on each node host, ensure that the DNS server that has the wildcard entry is not listed as a nameserver or that the wildcard domain is not listed in the search list. Otherwise, containers managed by OpenShift Container Platform may fail to resolve host names properly.

Network Access

A shared network must exist between the master and node hosts. If you plan to configure multiple masters for high-availability using the advanced installation method, you must also select an IP to be configured as your virtual IP (VIP) during the installation process. The IP that you select must be routable between all of your nodes, and if you configure using a FQDN it should resolve on all nodes.

NetworkManager

NetworkManager, a program for providing detection and configuration for systems to automatically connect to the network, is required.

Required Ports

The OpenShift Container Platform installation automatically creates a set of internal firewall rules on each host using iptables. However, if your network configuration uses an external firewall, such as a hardware-based firewall, you must ensure infrastructure components can communicate with each other through specific ports that act as communication endpoints for certain processes or services.

Ensure the following ports required by OpenShift Container Platform are open on your network and configured to allow access between hosts. Some ports are optional depending on your configuration and usage.

Table 2.1. Node to Node

4789

UDP

Required for SDN communication between pods on separate hosts.

Table 2.2. Nodes to Master

53 or 8053

TCP/UDP

Required for DNS resolution of cluster services (SkyDNS). Installations prior to 3.2 or environments upgraded to 3.2 use port 53. New installations will use 8053 by default so that dnsmasq may be configured.

4789

UDP

Required for SDN communication between pods on separate hosts.

443 or 8443

TCP

Required for node hosts to communicate to the master API, for the node hosts to post back status, to receive tasks, and so on.

Table 2.3. Master to Node

4789

UDP

Required for SDN communication between pods on separate hosts.

10250

TCP

The master proxies to node hosts via the Kubelet for oc commands.

Note

In the following table, (L) indicates the marked port is also used in loopback mode, enabling the master to communicate with itself.

In a single-master cluster:

Ports marked with (L) must be open.

Ports not marked with (L) need not be open.

In a multiple-master cluster, all the listed ports must be open.

Table 2.4. Master to Master

53 (L) or 8053 (L)

TCP/UDP

Required for DNS resolution of cluster services (SkyDNS). Installations prior to 3.2 or environments upgraded to 3.2 use port 53. New installations will use 8053 by default so that dnsmasq may be configured.

2049 (L)

TCP/UDP

Required when provisioning an NFS host as part of the installer.

2379

TCP

Used for standalone etcd (clustered) to accept changes in state.

2380

TCP

etcd requires this port be open between masters for leader election and peering connections when using standalone etcd (clustered).

4001 (L)

TCP

Used for embedded etcd (non-clustered) to accept changes in state.

4789 (L)

UDP

Required for SDN communication between pods on separate hosts.

Table 2.5. External to Load Balancer

9000

TCP

If you choose the native HA method, optional to allow access to the HAProxy statistics page.

Table 2.6. External to Master

443 or 8443

TCP

Required for node hosts to communicate to the master API, for node hosts to post back status, to receive tasks, and so on.

Table 2.7. IaaS Deployments

22

TCP

Required for SSH by the installer or system administrator.

53 or 8053

TCP/UDP

Required for DNS resolution of cluster services (SkyDNS). Installations prior to 3.2 or environments upgraded to 3.2 use port 53. New installations will use 8053 by default so that dnsmasq may be configured. Only required to be internally open on master hosts.

80 or 443

TCP

For HTTP/HTTPS use for the router. Required to be externally open on node hosts, especially on nodes running the router.

1936

TCP

For router statistics use. Required to be open when running the template router to access statistics, and can be open externally or internally to connections depending on if you want the statistics to be expressed publicly.

4001

TCP

For embedded etcd (non-clustered) use. Only required to be internally open on the master host. 4001 is for server-client connections.

2379 and 2380

TCP

For standalone etcd use. Only required to be internally open on the master host. 2379 is for server-client connections. 2380 is for server-server connections, and is only required if you have clustered etcd.

4789

UDP

For VxLAN use (OpenShift Container Platform SDN). Required only internally on node hosts.

8443

TCP

For use by the OpenShift Container Platform web console, shared with the API server.

10250

TCP

For use by the Kubelet. Required to be externally open on nodes.

Notes

In the above examples, port 4789 is used for User Datagram Protocol (UDP).

When deployments are using the SDN, the pod network is accessed via a service proxy, unless it is accessing the registry from the same node the registry is deployed on.

OpenShift Container Platform internal DNS cannot be received over SDN. Depending on the detected values of openshift_facts, or if the openshift_ip and openshift_public_ip values are overridden, it will be the computed value of openshift_ip. For non-cloud deployments, this will default to the IP address associated with the default route on the master host. For cloud deployments, it will default to the IP address associated with the first internal interface as defined by the cloud metadata.

The master host uses port 10250 to reach the nodes and does not go over SDN. It depends on the target host of the deployment and uses the computed values of openshift_hostname and openshift_public_hostname.

Table 2.8. Aggregated Logging

9200

TCP

For Elasticsearch API use. Required to be internally open on any infrastructure nodes so Kibana is able to retrieve logs for display. It can be externally opened for direct access to Elasticsearch by means of a route. The route can be created using oc expose.

9300

TCP

For Elasticsearch inter-cluster use. Required to be internally open on any infrastructure node so the members of the Elasticsearch cluster may communicate with each other.

Persistent Storage

The Kubernetes persistent volume framework allows you to provision an OpenShift Container Platform cluster with persistent storage using networked storage available in your environment. This can be done after completing the initial OpenShift Container Platform installation depending on your application needs, giving users a way to request those resources without having any knowledge of the underlying infrastructure.

The Installation and Configuration Guide provides instructions for cluster administrators on provisioning an OpenShift Container Platform cluster with persistent storage using NFS, GlusterFS, Ceph RBD, OpenStack Cinder, AWS Elastic Block Store (EBS), GCE Persistent Disks, and iSCSI.

Cloud Provider Considerations

There are certain aspects to take into consideration if installing OpenShift Container Platform on a cloud provider.

Configuring a Security Group

When installing on AWS or OpenStack, ensure that you set up the appropriate security groups. These are some ports that you should have in your security groups, without which the installation will fail. You may need more depending on the cluster configuration you want to install. For more information and to adjust your security groups accordingly, see Required Ports for more information.

All OpenShift Container Platform Hosts

tcp/22 from host running the installer/Ansible

etcd Security Group

tcp/2379 from masters

tcp/2380 from etcd hosts

Master Security Group

tcp/8443 from 0.0.0.0/0

tcp/53 from all OpenShift Container Platform hosts for environments installed prior to or upgraded to 3.2

udp/53 from all OpenShift Container Platform hosts for environments installed prior to or upgraded to 3.2

tcp/8053 from all OpenShift Container Platform hosts for new environments installed with 3.2

udp/8053 from all OpenShift Container Platform hosts for new environments installed with 3.2

Node Security Group

tcp/10250 from masters

tcp/4789 from nodes

Infrastructure Nodes (ones that can host the OpenShift Container Platform router)

tcp/443 from 0.0.0.0/0

tcp/80 from 0.0.0.0/0

If configuring ELBs for load balancing the masters and/or routers, you also need to configure Ingress and Egress security groups for the ELBs appropriately.

Overriding Detected IP Addresses and Host Names

Some deployments require that the user override the detected host names and IP addresses for the hosts. To see the default values, run the openshift_facts playbook:

# ansible-playbook playbooks/byo/openshift_facts.yml

Now, verify the detected common settings. If they are not what you expect them to be, you can override them.

The Advanced Installation topic discusses the available Ansible variables in greater detail.

Variable
Usage

hostname

Should resolve to the internal IP from the instances themselves.

openshift_hostname overrides.

ip

Should be the internal IP of the instance.

openshift_ip will overrides.

public_hostname

Should resolve to the external IP from hosts outside of the cloud.

Provider openshift_public_hostname overrides.

public_ip

Should be the externally accessible IP associated with the instance.

openshift_public_ip overrides.

use_openshift_sdn

Should be true unless the cloud is GCE.

openshift_use_openshift_sdn overrides.

Warning

If openshift_hostname is set to a value other than the metadata-provided private-dns-name value, the native cloud integration for those providers will no longer work.

In AWS, situations that require overriding the variables include:

Variable
Usage

hostname

The user is installing in a VPC that is not configured for both DNS hostnames and DNS resolution.

ip

Possibly if they have multiple network interfaces configured and they want to use one other than the default. You must first set openshift_node_set_node_ip to True. Otherwise, the SDN would attempt to use the hostname setting or try to resolve the host name for the IP.

public_hostname

A master instance where the VPC subnet is not configured for Auto-assign Public IP. For external access to this master, you need to have an ELB or other load balancer configured that would provide the external access needed, or you need to connect over a VPN connection to the internal name of the host.

A master instance where metadata is disabled.

This value is not actually used by the nodes.

public_ip

A master instance where the VPC subnet is not configured for Auto-assign Public IP.

A master instance where metadata is disabled.

This value is not actually used by the nodes.

If setting openshift_hostname to something other than the metadata-provided private-dns-name value, the native cloud integration for those providers will no longer work.

For EC2 hosts in particular, they must be deployed in a VPC that has both DNS host names and DNS resolution enabled, and openshift_hostname should not be overridden.

Post-Installation Configuration for Cloud Providers

Following the installation process, you can configure OpenShift Container Platform for AWS, OpenStack, or GCE.

Host Preparation

Operating System Requirements

A base installation of RHEL 7.1 or later or RHEL Atomic Host 7.2.6 or later is required for master and node hosts. See the following documentation for the respective installation instructions, if required:

Red Hat Enterprise Linux 7 Installation Guide

Red Hat Enterprise Linux Atomic Host 7 Installation and Configuration Guide

Host Registration

Each host must be registered using Red Hat Subscription Manager (RHSM) and have an active OpenShift Container Platform subscription attached to access the required packages.

On each host, register with RHSM:

# subscription-manager register --username=<user_name> --password=<password>

List the available subscriptions:

# subscription-manager list --available --matches '*OpenShift*'

In the output for the previous command, find the pool ID for an OpenShift Container Platform subscription and attach it:

# subscription-manager attach --pool=<pool_id>

Disable all yum repositories:

Disable all the enabled RHSM repositories:

# subscription-manager repos --disable="*"

List the remaining yum repositories and note their names under repo id, if any:

# yum repolist

Use yum-config-manager to disable the remaining yum repositories:

# yum-config-manager --disable <repo_id>

Alternatively, disable all repositories:

 yum-config-manager --disable \*

Note that this could take a few minutes if you have a large number of available repositories

Enable only the repositories required by OpenShift Container Platform 3.4:

# subscription-manager repos \
    --enable="rhel-7-server-rpms" \
    --enable="rhel-7-server-extras-rpms" \
    --enable="rhel-7-server-ose-3.3-rpms"

Installing Base Packages

For RHEL 7 systems:

Install the following base packages:

# yum install wget git net-tools bind-utils iptables-services bridge-utils bash-completion

Update the system to the latest packages:

# yum update

Install the following package, which provides OpenShift Container Platform utilities and pulls in other tools required by the quick and advanced installation methods, such as Ansible and related configuration files:

# yum install atomic-openshift-utils

Install the following *-excluder packages on each RHEL 7 system, which helps ensure your systems stay on the correct versions of atomic-openshift and docker packages when you are not trying to upgrade, according to the OpenShift Container Platform version:

# yum install atomic-openshift-excluder atomic-openshift-docker-excluder

Warning

There is a known issue (BZ#1417723) with the atomic-openshift-docker-excluder script in the OpenShift Container Platform 3.3 channel where the docker*1.12* does not get added to the host’s /etc/yum.conf file. This can cause Docker 1.12 to be installed on OpenShift Container Platform 3.3 hosts, which is not supported.

A fix will be provided in an upcoming release, but as a workaround, manually add docker*1.12* in the list on each host:

exclude=docker*1.12* [...]

This ensures that hosts will not accidentally upgrade past Docker 1.10.

The *-excluder packages add entries to the exclude directive in the host’s /etc/yum.conf file when installed. Run the following command on each host to remove the atomic-openshift packages from the list for the duration of the installation.

# atomic-openshift-excluder unexclude

For RHEL Atomic Host 7 systems:

Ensure the host is up to date by upgrading to the latest Atomic tree if one is available:

# atomic host upgrade

After the upgrade is completed and prepared for the next boot, reboot the host:

# systemctl reboot

Installing Docker

At this point, you should install Docker on all master and node hosts. This allows you to configure your Docker storage options before installing OpenShift Container Platform.

For RHEL 7 systems, install Docker 1.10.

Note

On RHEL Atomic Host 7 systems, Docker should already be installed, configured, and running by default.

The atomic-openshift-docker-excluder package that was installed in Installing Base Packages should ensure that the correct version of Docker is installed in this step:

# yum install docker

After the package installation is complete, verify that version 1.10.3 was installed:

# docker version

Edit the /etc/sysconfig/docker file and add --insecure-registry 172.30.0.0/16 to the OPTIONS parameter. For example:

OPTIONS='--selinux-enabled --insecure-registry 172.30.0.0/16'

If using the Quick Installation method, you can easily script a complete installation from a kickstart or cloud-init setup, change the default configuration file:

# sed -i '/OPTIONS=.*/c\OPTIONS="--selinux-enabled --insecure-registry 172.30.0.0/16"' \
/etc/sysconfig/docker

Note

The Advanced Installation method automatically changes /etc/sysconfig/docker.

The --insecure-registry option instructs the Docker daemon to trust any Docker registry on the indicated subnet, rather than requiring a certificate.

Important

172.30.0.0/16 is the default value of the servicesSubnet variable in the master-config.yaml file. If this has changed, then the --insecure-registry value in the above step should be adjusted to match, as it is indicating the subnet for the registry to use. Note that the openshift_master_portal_net variable can be set in the Ansible inventory file and used during the advanced installation method to modify the servicesSubnet variable.

Note

After the initial OpenShift Container Platform installation is complete, you can choose to secure the integrated Docker registry, which involves adjusting the --insecure-registry option accordingly.

Configuring Docker Storage

Containers and the images they are created from are stored in Docker’s storage back end. This storage is ephemeral and separate from any persistent storage allocated to meet the needs of your applications.

For RHEL Atomic Host

The default storage back end for Docker on RHEL Atomic Host is a thin pool logical volume, which is supported for production environments. You must ensure that enough space is allocated for this volume per the Docker storage requirements mentioned in System Requirements.

If you do not have enough allocated, see Managing Storage with Docker Formatted Containers for details on using docker-storage-setup and basic instructions on storage management in RHEL Atomic Host.

For RHEL

The default storage back end for Docker on RHEL 7 is a thin pool on loopback devices, which is not supported for production use and only appropriate for proof of concept environments. For production environments, you must create a thin pool logical volume and re-configure Docker to use that volume.

You can use the docker-storage-setup script included with Docker to create a thin pool device and configure Docker’s storage driver. This can be done after installing Docker and should be done before creating images or containers. The script reads configuration options from the /etc/sysconfig/docker-storage-setup file and supports three options for creating the logical volume:

Option A) Use an additional block device.

Option B) Use an existing, specified volume group.

Option C) Use the remaining free space from the volume group where your root file system is located.

Option A is the most robust option, however it requires adding an additional block device to your host before configuring Docker storage. Options B and C both require leaving free space available when provisioning your host.

Create the docker-pool volume using one of the following three options:

Option A) Use an additional block device.

In /etc/sysconfig/docker-storage-setup, set DEVS to the path of the block device you wish to use. Set VG to the volume group name you wish to create; docker-vg is a reasonable choice. For example:

# cat <<EOF > /etc/sysconfig/docker-storage-setup
DEVS=/dev/vdc
VG=docker-vg
EOF

Then run docker-storage-setup and review the output to ensure the docker-pool volume was created:

# docker-storage-setup                                                                                                                                                                                                                                [5/1868]
0
Checking that no-one is using this disk right now ...
OK

Disk /dev/vdc: 31207 cylinders, 16 heads, 63 sectors/track
sfdisk:  /dev/vdc: unrecognized partition table type

Old situation:
sfdisk: No partitions found

New situation:
Units: sectors of 512 bytes, counting from 0

   Device Boot    Start       End   #sectors  Id  System
/dev/vdc1          2048  31457279   31455232  8e  Linux LVM
/dev/vdc2             0         -          0   0  Empty
/dev/vdc3             0         -          0   0  Empty
/dev/vdc4             0         -          0   0  Empty
Warning: partition 1 does not start at a cylinder boundary
Warning: partition 1 does not end at a cylinder boundary
Warning: no primary partition is marked bootable (active)
This does not matter for LILO, but the DOS MBR will not boot this disk.
Successfully wrote the new partition table

Re-reading the partition table ...

If you created or changed a DOS partition, /dev/foo7, say, then use dd(1)
to zero the first 512 bytes:  dd if=/dev/zero of=/dev/foo7 bs=512 count=1
(See fdisk(8).)
  Physical volume "/dev/vdc1" successfully created
  Volume group "docker-vg" successfully created
  Rounding up size to full physical extent 16.00 MiB
  Logical volume "docker-poolmeta" created.
  Logical volume "docker-pool" created.
  WARNING: Converting logical volume docker-vg/docker-pool and docker-vg/docker-poolmeta to pool's data and metadata volumes.
  THIS WILL DESTROY CONTENT OF LOGICAL VOLUME (filesystem etc.)
  Converted docker-vg/docker-pool to thin pool.
  Logical volume "docker-pool" changed.

Option B) Use an existing, specified volume group.

In /etc/sysconfig/docker-storage-setup, set VG to the desired volume group. For example:

# cat <<EOF > /etc/sysconfig/docker-storage-setup
VG=docker-vg
EOF

Then run docker-storage-setup and review the output to ensure the docker-pool volume was created:

# docker-storage-setup
  Rounding up size to full physical extent 16.00 MiB
  Logical volume "docker-poolmeta" created.
  Logical volume "docker-pool" created.
  WARNING: Converting logical volume docker-vg/docker-pool and docker-vg/docker-poolmeta to pool's data and metadata volumes.
  THIS WILL DESTROY CONTENT OF LOGICAL VOLUME (filesystem etc.)
  Converted docker-vg/docker-pool to thin pool.
  Logical volume "docker-pool" changed.

Option C) Use the remaining free space from the volume group where your root file system is located.

Verify that the volume group where your root file system resides has the desired free space, then run docker-storage-setup and review the output to ensure the docker-pool volume was created:

# docker-storage-setup
  Rounding up size to full physical extent 32.00 MiB
  Logical volume "docker-poolmeta" created.
  Logical volume "docker-pool" created.
  WARNING: Converting logical volume rhel/docker-pool and rhel/docker-poolmeta to pool's data and metadata volumes.
  THIS WILL DESTROY CONTENT OF LOGICAL VOLUME (filesystem etc.)
  Converted rhel/docker-pool to thin pool.
  Logical volume "docker-pool" changed.

Verify your configuration. You should have a dm.thinpooldev value in the /etc/sysconfig/docker-storage file and a docker-pool logical volume:

# cat /etc/sysconfig/docker-storage
DOCKER_STORAGE_OPTIONS=--storage-opt dm.fs=xfs --storage-opt
dm.thinpooldev=/dev/mapper/docker--vg-docker--pool

# lvs
  LV          VG   Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  docker-pool rhel twi-a-t---  9.29g             0.00   0.12

Important

Before using Docker or OpenShift Container Platform, verify that the docker-pool logical volume is large enough to meet your needs. The docker-pool volume should be 60% of the available volume group and will grow to fill the volume group via LVM monitoring.

Check if Docker is running:

# systemctl is-active docker

If Docker has not yet been started on the host, enable and start the service:

# systemctl enable docker
# systemctl start docker

If Docker is already running, re-initialize Docker:

Warning

This will destroy any containers or images currently on the host.

# systemctl stop docker
# rm -rf /var/lib/docker/*
# systemctl restart docker

If there is any content in /var/lib/docker/, it must be deleted. Files will be present if Docker has been used prior to the installation of OpenShift Container Platform.

Reconfiguring Docker Storage

Should you need to reconfigure Docker storage after having created the docker-pool, you should first remove the docker-pool logical volume. If you are using a dedicated volume group, you should also remove the volume group and any associated physical volumes before reconfiguring docker-storage-setup according to the instructions above.

See Logical Volume Manager Administration for more detailed information on LVM management.

Managing Container Logs

Sometimes a container’s log file (the /var/lib/docker/containers/<hash>/<hash>-json.log file on the node where the container is running) can increase to a problematic size. You can manage this by configuring Docker’s json-file logging driver to restrict the size and number of log files.

Option
Purpose

--log-opt max-size

Sets the size at which a new log file is created.

--log-opt max-file

Sets the file on each host to configure the options.

For example, to set the maximum file size to 1MB and always keep the last three log files, edit the /etc/sysconfig/docker file to configure max-size=1M and max-file=3:

OPTIONS='--insecure-registry=172.30.0.0/16 --selinux-enabled --log-opt max-size=1M --log-opt max-file=3'

Next, restart the Docker service:

# systemctl restart docker

Viewing Available Container Logs

Container logs are stored in the /var/lib/docker/containers/<hash>/ directory on the node where the container is running. For example:

# ls -lh /var/lib/docker/containers/f088349cceac173305d3e2c2e4790051799efe363842fdab5732f51f5b001fd8/
total 2.6M
-rw-r--r--. 1 root root 5.6K Nov 24 00:12 config.json
-rw-r--r--. 1 root root 649K Nov 24 00:15 f088349cceac173305d3e2c2e4790051799efe363842fdab5732f51f5b001fd8-json.log
-rw-r--r--. 1 root root 977K Nov 24 00:15 f088349cceac173305d3e2c2e4790051799efe363842fdab5732f51f5b001fd8-json.log.1
-rw-r--r--. 1 root root 977K Nov 24 00:15 f088349cceac173305d3e2c2e4790051799efe363842fdab5732f51f5b001fd8-json.log.2
-rw-r--r--. 1 root root 1.3K Nov 24 00:12 hostconfig.json
drwx------. 2 root root    6 Nov 24 00:12 secrets

See Docker’s documentation for additional information on how to Configure Logging Drivers.

Ensuring Host Access

The quick and advanced installation methods require a user that has access to all hosts. If you want to run the installer as a non-root user, passwordless sudo rights must be configured on each destination host.

For example, you can generate an SSH key on the host where you will invoke the installation process:

# ssh-keygen

Do not use a password.

An easy way to distribute your SSH keys is by using a bash loop:

# for host in master.example.com \
    node1.example.com \
    node2.example.com; \
    do ssh-copy-id -i ~/.ssh/id_rsa.pub $host; \
    done

Modify the host names in the above command according to your configuration.

What’s Next?

If you are interested in installing OpenShift Container Platform using the containerized method (optional for RHEL but required for RHEL Atomic Host), see Containerized Components to prepare your hosts.

When you are ready to proceed, you can install OpenShift Container Platform using the quick installation or advanced installation method.

If you are installing a stand-alone registry, continue with Installing a Stand-alone Registry.

Containerized Components

Overview

This section explores some of the preparation required to install OpenShift Container Platform as a set of services within containers. This applies to hosts using either Red Hat Enterprise Linux or Red Hat Atomic Host.

For the quick installation method, you can choose between the RPM or containerized method on a per host basis during the interactive installation, or set the values manually in an installation configuration file.

For the advanced installation method, you can set the Ansible variable containerized=true in an inventory file on a cluster-wide or per host basis.

Note

When installing an environment with multiple masters, the load balancer cannot be deployed by the installation process as a container. See Advanced Installation for load balancer requirements using the native HA method.

The following sections detail the preparation for a containerized OpenShift Container Platform installation.

Required Images

Containerized installations make use of the following images:

openshift3/ose

openshift3/node

openshift3/openvswitch

registry.access.redhat.com/rhel7/etcd

By default, all of the above images are pulled from the Red Hat Registry at registry.access.redhat.com.

If you need to use a private registry to pull these images during the installation, you can specify the registry information ahead of time. For the advanced installation method, you can set the following Ansible variables in your inventory file, as required:

cli_docker_additional_registries=<registry_hostname>
cli_docker_insecure_registries=<registry_hostname>
cli_docker_blocked_registries=<registry_hostname>

For the quick installation method, you can export the following environment variables on each target host:

# export OO_INSTALL_ADDITIONAL_REGISTRIES=<registry_hostname>
# export OO_INSTALL_INSECURE_REGISTRIES=<registry_hostname>

Blocked Docker registries cannot currently be specified using the quick installation method.

The configuration of additional, insecure, and blocked Docker registries occurs at the beginning of the installation process to ensure that these settings are applied before attempting to pull any of the required images.

CLI Wrappers

When using containerized installations, a CLI wrapper script is deployed on each master at /usr/local/bin/openshift. The following set of symbolic links are also provided to ease administrative tasks:

Symbolic Link
Usage

/usr/local/bin/oc

Developer CLI

/usr/local/bin/oadm

Administrative CLI

/usr/local/bin/kubectl

Kubernetes CLI

The wrapper spawns a new container on each invocation, so you may notice it run slightly slower than native CLI operations.

The wrapper scripts mount a limited subset of paths:

~/.kube

/etc/origin/

/tmp/

Be mindful of this when passing in files to be processed by the oc or oadm commands. You may find it easier to redirect the input, for example:

# oc create -f - < my-file.json

Note

The wrapper is intended only to be used to bootstrap an environment. You should install the CLI tools on another host after you have granted cluster-admin privileges to a user. See Managing Role Bindings and Get Started with the CLI for more information.

Starting and Stopping Containers

The installation process creates relevant systemd units which can be used to start, stop, and poll services using normal systemctl commands. For containerized installations, these unit names match those of an RPM installation, with the exception of the etcd service which is named etcd_container.

This change is necessary as currently RHEL Atomic Host ships with the etcd package installed as part of the operating system, so a containerized version is used for the OpenShift Container Platform installation instead. The installation process disables the default etcd service. The etcd package is slated to be removed from RHEL Atomic Host in the future.

File Paths

All OpenShift configuration files are placed in the same locations during containerized installation as RPM based installations and will survive os-tree upgrades.

However, the default image stream and template files are installed at /etc/origin/examples/ for containerized installations rather than the standard /usr/share/openshift/examples/, because that directory is read-only on RHEL Atomic Host.

Storage Requirements

RHEL Atomic Host installations normally have a very small root file system. However, the etcd, master, and node containers persist data in the /var/lib/ directory. Ensure that you have enough space on the root file system before installing OpenShift Container Platform; see the System Requirements section for details.

Open vSwitch SDN Initialization

OpenShift Container Platform SDN initialization requires that the Docker bridge be reconfigured and that Docker is restarted. This complicates the situation when the node is running within a container. When using the Open vSwitch (OVS) SDN, you will see the node start, reconfigure Docker, restart Docker (which restarts all containers), and finally start successfully.

In this case, the node service may fail to start and be restarted a few times because the master services are also restarted along with Docker. The current implementation uses a workaround which relies on setting the Restart=always parameter in the Docker based systemd units.

Quick Installation

Overview

The quick installation method allows you to use an interactive CLI utility, the atomic-openshift-installer command, to install OpenShift Container Platform across a set of hosts. This installer can deploy OpenShift Container Platform components on targeted hosts by either installing RPMs or running containerized services.

This installation method is provided to make the installation experience easier by interactively gathering the data needed to run on each host. The installer is a self-contained wrapper intended for usage on a Red Hat Enterprise Linux (RHEL) 7 system. While RHEL Atomic Host is supported for running containerized OpenShift Container Platform services, the installer is provided by an RPM not available by default in RHEL Atomic Host, and must therefore be run from a RHEL 7 system. The host initiating the installation does not need to be intended for inclusion in the OpenShift Container Platform cluster, but it can be.

In addition to running interactive installations from scratch, the atomic-openshift-installer command can also be run or re-run using a predefined installation configuration file. This file can be used with the installer to:

run an unattended installation,

add nodes to an existing cluster,

upgrade your cluster, or

reinstall the OpenShift Container Platform cluster completely.

Alternatively, you can use the advanced installation method for more complex environments.

Note

To install OpenShift Container Platform as a stand-alone registry, see Installing a Stand-alone Registry.

Before You Begin

The installer allows you to install OpenShift Container Platform master and node components on a defined set of hosts.

Note

By default, any hosts you designate as masters during the installation process are automatically also configured as nodes so that the masters are configured as part of the OpenShift Container Platform SDN. The node component on the masters, however, are marked unschedulable, which blocks pods from being scheduled on it. After the installation, you can mark them schedulable if you want.

Before installing OpenShift Container Platform, you must first satisfy the prerequisites on your hosts, which includes verifying system and environment requirements and properly installing and configuring Docker. You must also be prepared to provide or validate the following information for each of your targeted hosts during the course of the installation:

User name on the target host that should run the Ansible-based installation (can be root or non-root)

Host name

Whether to install components for master, node, or both

Whether to use the RPM or containerized method

Internal and external IP addresses

If you are interested in installing OpenShift Container Platform using the containerized method (optional for RHEL but required for RHEL Atomic Host), see RPM vs Containerized to ensure that you understand the differences between these methods, then return to this topic to continue.

After following the instructions in the Prerequisites topic and deciding between the RPM and containerized methods, you can continue to running an interactive or unattended installation.

Running an Interactive Installation

Note

Ensure you have read through Before You Begin.

You can start the interactive installation by running:

$ atomic-openshift-installer install

Then follow the on-screen instructions to install a new OpenShift Container Platform cluster.

After it has finished, ensure that you back up the ~/.config/openshift/installer.cfg.ymlinstallation configuration file that is created, as it is required if you later want to re-run the installation, add hosts to the cluster, or upgrade your cluster. Then, verify the installation.

Defining an Installation Configuration File

The installer can use a predefined installation configuration file, which contains information about your installation, individual hosts, and cluster. When running an interactive installation, an installation configuration file based on your answers is created for you in ~/.config/openshift/installer.cfg.yml. The file is created if you are instructed to exit the installation to manually modify the configuration or when the installation completes. You can also create the configuration file manually from scratch to perform an unattended installation.

Example 2.1. Installation Configuration File Specification

version: v2
variant: openshift-enterprise
variant_version: 3.3
ansible_log_path: /tmp/ansible.log
deployment:
  ansible_ssh_user: root
  hosts:
  - ip: 10.0.0.1
    hostname: master-private.example.com
    public_ip: 24.222.0.1
    public_hostname: master.example.com
    roles:
      - master
      - node
    containerized: true
    connect_to: 24.222.0.1
  - ip: 10.0.0.2
    hostname: node1-private.example.com
    public_ip: 24.222.0.2
    public_hostname: node1.example.com
    node_labels: {'region': 'infra'}
    roles:
      - node
    connect_to: 10.0.0.2
  - ip: 10.0.0.3
    hostname: node2-private.example.com
    public_ip: 24.222.0.3
    public_hostname: node2.example.com
    roles:
      - node
    connect_to: 10.0.0.3
  roles:
    master:
      <variable_name1>: "<value1>" (16)
      <variable_name2>: "<value2>"
    node:
      <variable_name1>: "<value1>" (17)

The version of this installation configuration file. As of OpenShift Container Platform 3.3, the only valid version here is v2.

The OpenShift Container Platform variant to install. For OpenShift Container Platform, set this to openshift-enterprise.

A valid version of your selected variant: 3.3, 3.2, or 3.1. If not specified, this defaults to the latest version for the specified variant.

Defines where the Ansible logs are stored. By default, this is the /tmp/ansible.log file.

Defines which user Ansible uses to SSH in to remote systems for gathering facts and for the installation. By default, this is the root user, but you can set it to any user that has sudo privileges.

Defines a list of the hosts onto which you want to install the OpenShift Container Platform master and node components.

Required. Allows the installer to connect to the system and gather facts before proceeding with the install.

Required for unattended installations. If these details are not specified, then this information is pulled from the facts gathered by the installer, and you are asked to confirm the details. If undefined for an unattended installation, the installation fails.

Determines the type of services that are installed. Specified as a list.

If set to true, containerized OpenShift Container Platform services are run on target master and node hosts instead of installed using RPM packages. If set to false or unset, the default RPM method is used. RHEL Atomic Host requires the containerized method, and is automatically selected for you based on the detection of the /run/ostree-booted file. See RPM vs Containerized for more details.

The IP address that Ansible attempts to connect to when installing, upgrading, or uninstalling the systems. If the configuration file was auto-generated, then this is the value you first enter for the host during that interactive install process.

Node labels can optionally be set per-host.

Defines a dictionary of roles across the deployment.

(16) (17)

Any ansible variables that should only be applied to hosts assigned a role can be defined. For examples, see Configuring Ansible.

Running an Unattended Installation

Note

Ensure you have read through the Before You Begin.

Unattended installations allow you to define your hosts and cluster configuration in an installation configuration file before running the installer so that you do not have to go through all of the interactive installation questions and answers. It also allows you to resume an interactive installation you may have left unfinished, and quickly get back to where you left off.

To run an unattended installation, first define an installation configuration file at ~/.config/openshift/installer.cfg.yml. Then, run the installer with the -u flag:

$ atomic-openshift-installer -u install

By default in interactive or unattended mode, the installer uses the configuration file located at ~/.config/openshift/installer.cfg.yml if the file exists. If it does not exist, attempting to start an unattended installation fails.

Alternatively, you can specify a different location for the configuration file using the -c option, but doing so will require you to specify the file location every time you run the installation:

$ atomic-openshift-installer -u -c </path/to/file> install

After the unattended installation finishes, ensure that you back up the ~/.config/openshift/installer.cfg.yml file that was used, as it is required if you later want to re-run the installation, add hosts to the cluster, or upgrade your cluster. Then, verify the installation.

Verifying the Installation

After the installation completes:

Verify that the master is started and nodes are registered and reporting in Ready status. On the master host, run the following as root:

# oc get nodes

NAME                        STATUS                     AGE
master.example.com          Ready,SchedulingDisabled   165d
node1.example.com           Ready                      165d
node2.example.com           Ready                      165d

To verify that the web console is installed correctly, use the master host name and the console port number to access the console with a web browser.

For example, for a master host with a hostname of master.openshift.com and using the default port of 8443, the web console would be found at:

https://master.openshift.com:8443/console

Now that the install has been verified, run the following command on each master and node host to add the atomic-openshift packages back to the list of yum excludes on the host:

# atomic-openshift-excluder exclude

Then, see What’s Next for the next steps on configuring your OpenShift Container Platform cluster.

Uninstalling OpenShift Container Platform

You can uninstall OpenShift Container Platform on all hosts in your cluster using the installer by running:

$ atomic-openshift-installer uninstall

See the advanced installation method for more options.

What’s Next?

Now that you have a working OpenShift Container Platform instance, you can:

Configure authentication; by default, authentication is set to Deny All.

Configure the automatically-deployed integrated Docker registry.

Configure the automatically-deployed router.

Advanced Installation

Overview

A reference configuration implemented using Ansible playbooks is available as the advanced installation method for installing a OpenShift Container Platform cluster. Familiarity with Ansible is assumed, however you can use this configuration as a reference to create your own implementation using the configuration management tool of your choosing.

While RHEL Atomic Host is supported for running containerized OpenShift Container Platform services, the advanced installation method utilizes Ansible, which is not available in RHEL Atomic Host, and must therefore be run from a RHEL 7 system. The host initiating the installation does not need to be intended for inclusion in the OpenShift Container Platform cluster, but it can be.

Alternatively, you can use the quick installation method if you prefer an interactive installation experience.

Note

To install OpenShift Container Platform as a stand-alone registry, see Installing a Stand-alone Registry.

Before You Begin

Before installing OpenShift Container Platform, you must first see the Prerequisites topic to prepare your hosts, which includes verifying system and environment requirements per component type and properly installing and configuring Docker. It also includes installing Ansible version 1.8.4 or later, as the advanced installation method is based on Ansible playbooks and as such requires directly invoking Ansible.

If you are interested in installing OpenShift Container Platform using the containerized method (optional for RHEL but required for RHEL Atomic Host), see RPM vs Containerized to ensure that you understand the differences between these methods, then return to this topic to continue.

After following the instructions in the Prerequisites topic and deciding between the RPM and containerized methods, you can continue in this topic to Configuring Ansible.

Configuring Ansible

The /etc/ansible/hosts file is Ansible’s inventory file for the playbook to use during the installation. The inventory file describes the configuration for your OpenShift Container Platform cluster. You must replace the default contents of the file with your desired configuration.

The following sections describe commonly-used variables to set in your inventory file during an advanced installation, followed by example inventory files you can use as a starting point for your installation. The examples describe various environment topographies, including using multiple masters for high availability. You can choose an example that matches your requirements, modify it to match your own environment, and use it as your inventory file when running the advanced installation.

Configuring Host Variables

To assign environment variables to hosts during the Ansible installation, indicate the desired variables in the /etc/ansible/hosts file after the host entry in the [masters] or [nodes] sections. For example:

[masters]
ec2-52-6-179-239.compute-1.amazonaws.com openshift_public_hostname=ose3-master.public.example.com

The following table describes variables for use with the Ansible installer that can be assigned to individual host entries:

Table 2.9. Host Variables

Variable
Purpose

openshift_hostname

This variable overrides the internal cluster host name for the system. Use this when the system’s default IP address does not resolve to the system host name.

openshift_public_hostname

This variable overrides the system’s public host name. Use this for cloud installations, or for hosts on networks using a network address translation (NAT).

openshift_ip

This variable overrides the cluster internal IP address for the system. Use this when using an interface that is not configured with the default route.

openshift_public_ip

This variable overrides the system’s public IP address. Use this for cloud installations, or for hosts on networks using a network address translation (NAT).

containerized

If set to true, containerized OpenShift Container Platform services are run on target master and node hosts instead of installed using RPM packages. If set to false or unset, the default RPM method is used. RHEL Atomic Host requires the containerized method, and is automatically selected for you based on the detection of the /run/ostree-booted file. See RPM vs Containerized for more details. Containerized installations are supported starting in OpenShift Container Platform 3.1.1.

openshift_node_labels

This variable adds labels to nodes during installation. See Configuring Node Host Labels for more details.

openshift_node_kubelet_args

This variable is used to configure kubeletArguments on nodes, such as arguments used in container and image garbage collection, and to specify resources per node. kubeletArguments are key value pairs that are passed directly to the Kubelet that match the Kubelet’s command line arguments. kubeletArguments are not migrated or validated and may become invalid if used. These values override other settings in node configuration which may cause invalid configurations. Example usage: {'image-gc-high-threshold': ['90'],'image-gc-low-threshold': ['80']}.

openshift_hosted_router_selector

Default node selector for automatically deploying router pods. See Configuring Node Host Labels for details.

openshift_registry_selector

Default node selector for automatically deploying registry pods. See Configuring Node Host Labels for details.

openshift_docker_options

This variable configures additional Docker options within /etc/sysconfig/docker, such as options used in Managing Container Logs. Example usage: "--log-driver json-file --log-opt max-size=1M --log-opt max-file=3".

Configuring Cluster Variables

To assign environment variables during the Ansible install that apply more globally to your OpenShift Container Platform cluster overall, indicate the desired variables in the /etc/ansible/hosts file on separate, single lines within the [OSEv3:vars] section. For example:

[OSEv3:vars]

openshift_master_identity_providers=[{'name': 'htpasswd_auth',
'login': 'true', 'challenge': 'true',
'kind': 'HTPasswdPasswordIdentityProvider',
'filename': '/etc/origin/master/htpasswd'}]

openshift_master_default_subdomain=apps.test.example.com

The following table describes variables for use with the Ansible installer that can be assigned cluster-wide:

Table 2.10. Cluster Variables

Variable
Purpose

ansible_ssh_user

This variable sets the SSH user for the installer to use and defaults to root. This user should allow SSH-based authentication without requiring a password. If using SSH key-based authentication, then the key should be managed by an SSH agent.

ansible_become

If ansible_ssh_user is not root, this variable must be set to true and the user must be configured for passwordless sudo.

containerized

If set to true, containerized OpenShift Container Platform services are run on all target master and node hosts in the cluster instead of installed using RPM packages. If set to false or unset, the default RPM method is used. RHEL Atomic Host requires the containerized method, and is automatically selected for you based on the detection of the /run/ostree-booted file. See RPM vs Containerized for more details. Containerized installations are supported starting in OpenShift Container Platform 3.1.1.

openshift_master_cluster_hostname

This variable overrides the host name for the cluster, which defaults to the host name of the master.

openshift_master_cluster_public_hostname

This variable overrides the public host name for the cluster, which defaults to the host name of the master.

openshift_master_cluster_method

Optional. This variable defines the HA method when deploying multiple masters. Supports the native method. See Multiple Masters for more information.

openshift_rolling_restart_mode

This variable enables rolling restarts of HA masters (i.e., masters are taken down one at a time) when running the upgrade playbook directly. It defaults to services, which allows rolling restarts of services on the masters. It can instead be set to system, which enables rolling, full system restarts and also works for single master clusters.

os_sdn_network_plugin_name

This variable configures which OpenShift Container Platform SDN plug-in to use for the pod network, which defaults to redhat/openshift-ovs-subnet for the standard SDN plug-in. Set the variable to redhat/openshift-ovs-multitenant to use the multitenant plug-in.

openshift_master_identity_providers

This variable overrides the identity provider, which defaults to Deny All.

openshift_master_named_certificates

These variables are used to configure custom certificates which are deployed as part of the installation. See Configuring Custom Certificates for more information.

openshift_master_overwrite_named_certificates

openshift_master_session_name

These variables override defaults for session options in the OAuth configuration. See Configuring Session Options for more information.

openshift_master_session_max_seconds

openshift_master_session_auth_secrets

openshift_master_session_encryption_secrets

openshift_master_portal_net

This variable configures the subnet in which services will be created within the OpenShift Container Platform SDN. This network block should be private and must not conflict with any existing network blocks in your infrastructure to which pods, nodes, or the master may require access to, or the installation will fail. Defaults to 172.30.0.0/16, and cannot be re-configured after deployment. If changing from the default, avoid 172.16.0.0/16, which the docker0 network bridge uses by default, or modify the docker0 network.

openshift_master_default_subdomain

This variable overrides the default subdomain to use for exposed routes.

openshift_node_proxy_mode

This variable specifies the service proxy mode to use: either iptables for the default, pure-iptables implementation, or userspace for the user space proxy.

osm_default_node_selector

This variable overrides the node selector that projects will use by default when placing pods.

osm_cluster_network_cidr

This variable overrides the SDN cluster network CIDR block. This is the network from which pod IPs are assigned. This network block should be a private block and must not conflict with existing network blocks in your infrastructure to which pods, nodes, or the master may require access. Defaults to 10.128.0.0/14 and cannot be arbitrarily re-configured after deployment, although certain changes to it can be made in the SDN master configuration.

osm_host_subnet_length

This variable specifies the size of the per host subnet allocated for pod IPs by OpenShift Container Platform SDN. Defaults to 9 which means that a subnet of size /23 is allocated to each host; for example, given the default 10.128.0.0/14 cluster network, this will allocate 10.128.0.0/23, 10.128.2.0/23, 10.128.4.0/23, and so on. This cannot be re-configured after deployment.

openshift_docker_additional_registries

OpenShift Container Platform adds the specified additional registry or registries to the Docker configuration.

openshift_docker_insecure_registries

OpenShift Container Platform adds the specified additional insecure registry or registries to the Docker configuration.

openshift_docker_blocked_registries

OpenShift Container Platform adds the specified blocked registry or registries to the Docker configuration.

openshift_hosted_metrics_public_url

This variable sets the host name for integration with the metrics console. The default is https://hawkular-metrics.{{openshift_master_default_subdomain}}/hawkular/metrics If you alter this variable, ensure the host name is accessible via your router.

Configuring a Registry Location

If you are using an image registry other than the default at registry.access.redhat.com, specify the desired registry within the /etc/ansible/hosts file.

oreg_url=example.com/openshift3/ose-${component}:${version}
openshift_examples_modify_imagestreams=true

Table 2.11. Registry Variables

Variable
Purpose

oreg_url

Set to the alternate image location. Necessary if you are not using the default registry at registry.access.redhat.com.

openshift_examples_modify_imagestreams

Set to true if pointing to a registry other than the default. Modifies the image stream location to the value of oreg_url.

Configuring Global Proxy Options

If your hosts require use of a HTTP or HTTPS proxy in order to connect to external hosts, there are many components that must be configured to use the proxy, including masters, Docker, and builds. Node services only connect to the master API requiring no external access and therefore do not need to be configured to use a proxy.

In order to simplify this configuration, the following Ansible variables can be specified at a cluster or host level to apply these settings uniformly across your environment.

Note

See Configuring Global Build Defaults and Overrides for more information on how the proxy environment is defined for builds.

Table 2.12. Cluster Proxy Variables

Variable
Purpose

openshift_http_proxy

This variable specifies the HTTP_PROXY environment variable for masters and the Docker daemon.

openshift_https_proxy

This variable specifices the HTTPS_PROXY environment variable for masters and the Docker daemon.

openshift_no_proxy

This variable is used to set the NO_PROXY environment variable for masters and the Docker daemon. This value should be set to a comma separated list of host names or wildcard host names that should not use the defined proxy. This list will be augmented with the list of all defined OpenShift Container Platform host names by default.

openshift_generate_no_proxy_hosts

This boolean variable specifies whether or not the names of all defined OpenShift hosts and *.cluster.local should be automatically appended to the NO_PROXY list. Defaults to true; set it to false to override this option.

openshift_builddefaults_http_proxy

This variable defines the HTTP_PROXY environment variable inserted into builds using the BuildDefaults admission controller. If openshift_http_proxy is set, this variable will inherit that value; you only need to set this if you want your builds to use a different value.

openshift_builddefaults_https_proxy

This variable defines the HTTPS_PROXY environment variable inserted into builds using the BuildDefaults admission controller. If openshift_https_proxy is set, this variable will inherit that value; you only need to set this if you want your builds to use a different value.

openshift_builddefaults_no_proxy

This variable defines the NO_PROXY environment variable inserted into builds using the BuildDefaults admission controller. If openshift_no_proxy is set, this variable will inherit that value; you only need to set this if you want your builds to use a different value.

openshift_builddefaults_git_http_proxy

This variable defines the HTTP proxy used by git clone operations during a build, defined using the BuildDefaults admission controller. If openshift_builddefaults_http_proxy is set, this variable will inherit that value; you only need to set this if you want your git clone operations to use a different value.

openshift_builddefaults_git_https_proxy

This variable defines the HTTPS proxy used by git clone operations during a build, defined using the BuildDefaults admission controller. If openshift_builddefaults_https_proxy is set, this variable will inherit that value; you only need to set this if you want your git clone operations to use a different value.

Configuring Node Host Labels

You can assign labels to node hosts during the Ansible install by configuring the /etc/ansible/hosts file. Labels are useful for determining the placement of pods onto nodes using the scheduler. Other than region=infra (discussed below), the actual label names and values are arbitrary and can be assigned however you see fit per your cluster’s requirements.

To assign labels to a node host during an Ansible install, use the openshift_node_labels variable with the desired labels added to the desired node host entry in the [nodes] section. In the following example, labels are set for a region called primary and a zone called east:

[nodes]
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"

The openshift_router_selector and openshift_registry_selector Ansible settings are set to region=infra by default:

# default selectors for router and registry services
# openshift_router_selector='region=infra'
# openshift_registry_selector='region=infra'

The default router and registry will be automatically deployed if nodes exist that match the selector settings above. For example:

[nodes]
node1.example.com openshift_node_labels="{'region':'infra','zone':'default'}"

Marking Masters as Unschedulable Nodes

Any hosts you designate as masters during the installation process should also be configured as nodes by adding them to the [nodes] section so that the masters are configured as part of the OpenShift Container Platform SDN.

However, in order to ensure that your masters are not burdened with running pods, you can make them unschedulable by adding the openshift_scheduleable=false option any node that is also a master. For example:

[nodes]
master.example.com openshift_node_labels="{'region':'infra','zone':'default'}" openshift_schedulable=false

Configuring Session Options

Session options in the OAuth configuration are configurable in the inventory file. By default, Ansible populates a sessionSecretsFile with generated authentication and encryption secrets so that sessions generated by one master can be decoded by the others. The default location is /etc/origin/master/session-secrets.yaml, and this file will only be re-created if deleted on all masters.

You can set the session name and maximum number of seconds with openshift_master_session_name and openshift_master_session_max_seconds:

openshift_master_session_name=ssn
openshift_master_session_max_seconds=3600

If provided, openshift_master_session_auth_secrets and openshift_master_encryption_secrets must be equal length.

For openshift_master_session_auth_secrets, used to authenticate sessions using HMAC, it is recommended to use secrets with 32 or 64 bytes:

openshift_master_session_auth_secrets=['DONT+USE+THIS+SECRET+b4NV+pmZNSO']

For openshift_master_encryption_secrets, used to encrypt sessions, secrets must be 16, 24, or 32 characters long, to select AES-128, AES-192, or AES-256:

openshift_master_session_encryption_secrets=['DONT+USE+THIS+SECRET+b4NV+pmZNSO']

Configuring Custom Certificates

Custom serving certificates for the public host names of the OpenShift Container Platform API and web console can be deployed during an advanced installation and are configurable in the inventory file.

Note

Custom certificates should only be configured for the host name associated with the publicMasterURL which can be set using openshift_master_cluster_public_hostname. Using a custom serving certificate for the host name associated with the masterURL (openshift_master_cluster_hostname) will result in TLS errors as infrastructure components will attempt to contact the master API using the internal masterURL host.

Certificate and key file paths can be configured using the openshift_master_named_certificates cluster variable:

openshift_master_named_certificates=[{"certfile": "/path/to/custom1.crt", "keyfile": "/path/to/custom1.key"}]

File paths must be local to the system where Ansible will be run. Certificates are copied to master hosts and are deployed within the /etc/origin/master/named_certificates/ directory.

Ansible detects a certificate’s Common Name and Subject Alternative Names. Detected names can be overridden by providing the "names" key when setting openshift_master_named_certificates:

openshift_master_named_certificates=[{"certfile": "/path/to/custom1.crt", "keyfile": "/path/to/custom1.key", "names": ["public-master-host.com"]}]

Certificates configured using openshift_master_named_certificates are cached on masters, meaning that each additional Ansible run with a different set of certificates results in all previously deployed certificates remaining in place on master hosts and within the master configuration file.

If you would like openshift_master_named_certificates to be overwritten with the provided value (or no value), specify the openshift_master_overwrite_named_certificates cluster variable:

openshift_master_overwrite_named_certificates=true

For a more complete example, consider the following cluster variables in an inventory file:

openshift_master_cluster_method=native
openshift_master_cluster_hostname=lb.openshift.com
openshift_master_cluster_public_hostname=custom.openshift.com

To overwrite the certificates on a subsequent Ansible run, you could set the following:

openshift_master_named_certificates=[{"certfile": "/root/STAR.openshift.com.crt", "keyfile": "/root/STAR.openshift.com.key", "names": ["custom.openshift.com"]}]
openshift_master_overwrite_named_certificates=true

Configuring Cluster Metrics

Cluster metrics are not set to automatically deploy by default. Set the following to enable cluster metrics when using the advanced install:

[OSEv3:vars]

openshift_hosted_metrics_deploy=true

Metrics Storage

The openshift_hosted_metrics_storage_kind variable must be set in order to use persistent storage. If openshift_hosted_metrics_storage_kind is not set, then cluster metrics data is stored in an EmptyDir volume, which will be deleted when the Cassandra pod terminates.

There are three options for enabling cluster metrics storage when using the advanced install:

Option A - NFS Host Group

When the following variables are set, an NFS volume is created during an advanced install with path <nfs_directory>/<volume_name> on the host within the [nfs] host group. For example, the volume path using these options would be /exports/metrics:

[OSEv3:vars]

openshift_hosted_metrics_storage_kind=nfs
openshift_hosted_metrics_storage_access_modes=['ReadWriteOnce']
openshift_hosted_metrics_storage_nfs_directory=/exports
openshift_hosted_metrics_storage_nfs_options='*(rw,root_squash)'
openshift_hosted_metrics_storage_volume_name=metrics
openshift_hosted_metrics_storage_volume_size=10Gi

Option B - External NFS Host

To use an external NFS volume, one must already exist with a path of <nfs_directory>/<volume_name> on the storage host.

[OSEv3:vars]

openshift_hosted_metrics_storage_kind=nfs
openshift_hosted_metrics_storage_access_modes=['ReadWriteOnce']
openshift_hosted_metrics_storage_host=nfs.example.com
openshift_hosted_metrics_storage_nfs_directory=/exports
openshift_hosted_metrics_storage_volume_name=metrics
openshift_hosted_metrics_storage_volume_size=10Gi

The remote volume path using the following options would be nfs.example.com:/exports/metrics.

Option C - Dynamic

Use the following variable if your OpenShift Container Platform environment supports dynamic volume provisioning for your cloud platform:

[OSEv3:vars]

#openshift_hosted_metrics_storage_kind=dynamic

Single Master Examples

You can configure an environment with a single master and multiple nodes, and either a single embedded etcd or multiple external etcd hosts.

Note

Moving from a single master cluster to multiple masters after installation is not supported.

Single Master and Multiple Nodes

The following table describes an example environment for a single master (with embedded etcd) and two nodes:

Host Name
Infrastructure Component to Install

master.example.com

Master and node

node1.example.com

Node

node2.example.com

You can see these example hosts present in the [masters] and [nodes] sections of the following example inventory file:

Example 2.2. Single Master and Multiple Nodes Inventory File

# Create an OSEv3 group that contains the masters and nodes groups
[OSEv3:children]
masters
nodes

# Set variables common for all OSEv3 hosts
[OSEv3:vars]
# SSH user, this user should allow ssh based auth without requiring a password
ansible_ssh_user=root

# If ansible_ssh_user is not root, ansible_become must be set to true
#ansible_become=true

deployment_type=openshift-enterprise

# uncomment the following to enable htpasswd authentication; defaults to DenyAllPasswordIdentityProvider
#openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/htpasswd'}]

# host group for masters
[masters]
master.example.com

# host group for nodes, includes region info
[nodes]
master.example.com openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"
node2.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

To use this example, modify the file to match your environment and specifications, and save it as /etc/ansible/hosts.

Single Master, Multiple etcd, and Multiple Nodes

The following table describes an example environment for a single master, three etcd hosts, and two nodes:

Host Name
Infrastructure Component to Install

master.example.com

Master and node

etcd1.example.com

etcd

etcd2.example.com

etcd3.example.com

node1.example.com

Node

node2.example.com

Note

When specifying multiple etcd hosts, external etcd is installed and configured. Clustering of OpenShift Container Platform’s embedded etcd is not supported.

You can see these example hosts present in the [masters], [nodes], and [etcd] sections of the following example inventory file:

Example 2.3. Single Master, Multiple etcd, and Multiple Nodes Inventory File

# Create an OSEv3 group that contains the masters, nodes, and etcd groups
[OSEv3:children]
masters
nodes
etcd

# Set variables common for all OSEv3 hosts
[OSEv3:vars]
ansible_ssh_user=root
deployment_type=openshift-enterprise

# uncomment the following to enable htpasswd authentication; defaults to DenyAllPasswordIdentityProvider
#openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/htpasswd'}]

# host group for masters
[masters]
master.example.com

# host group for etcd
[etcd]
etcd1.example.com
etcd2.example.com
etcd3.example.com

# host group for nodes, includes region info
[nodes]
master.example.com openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"
node2.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

To use this example, modify the file to match your environment and specifications, and save it as /etc/ansible/hosts.

Multiple Masters Examples

You can configure an environment with multiple masters, multiple etcd hosts, and multiple nodes. Configuring multiple masters for high availability (HA) ensures that the cluster has no single point of failure.

Note

Moving from a single master cluster to multiple masters after installation is not supported.

When configuring multiple masters, the advanced installation supports the following high availability (HA) method:

native

Leverages the native HA master capabilities built into OpenShift Container Platform and can be combined with any load balancing solution. If a host is defined in the [lb] section of the inventory file, Ansible installs and configures HAProxy automatically as the load balancing solution. If no host is defined, it is assumed you have pre-configured a load balancing solution of your choice to balance the master API (port 8443) on all master hosts.

Note

For more on the high availability master architecture, see Kubernetes Infrastructure.

Note the following when using the native HA method:

The advanced installation method does not currently support multiple HAProxy load balancers in an active-passive setup. See the Load Balancer Administration documentation for post-installation amendments.

In a HAProxy setup, controller manager servers run as standalone processes. They elect their active leader with a lease stored in etcd. The lease expires after 30 seconds by default. If a failure happens on an active controller server, it will take up to this number of seconds to elect another leader. The interval can be configured with the osm_controller_lease_ttl variable.

To configure multiple masters, refer to the following section.

Multiple Masters with Multiple etcd, and Using Native HA

The following describes an example environment for three masters, one HAProxy load balancer, three etcd hosts, and two nodes using the native HA method:

Host Name
Infrastructure Component to Install

master1.example.com

Master (clustered using native HA) and node

master2.example.com

master3.example.com

lb.example.com

HAProxy to load balance API master endpoints

etcd1.example.com

etcd

etcd2.example.com

etcd3.example.com

node1.example.com

Node

node2.example.com

Note

When specifying multiple etcd hosts, external etcd is installed and configured. Clustering of OpenShift Container Platform’s embedded etcd is not supported.

You can see these example hosts present in the [masters], [etcd], [lb], and [nodes] sections of the following example inventory file:

Example 2.4. Multiple Masters Using HAProxy Inventory File

# Create an OSEv3 group that contains the master, nodes, etcd, and lb groups.
# The lb group lets Ansible configure HAProxy as the load balancing solution.
# Comment lb out if your load balancer is pre-configured.
[OSEv3:children]
masters
nodes
etcd
lb

# Set variables common for all OSEv3 hosts
[OSEv3:vars]
ansible_ssh_user=root
deployment_type=openshift-enterprise

# Uncomment the following to enable htpasswd authentication; defaults to
# DenyAllPasswordIdentityProvider.
#openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/htpasswd'}]

# Native high availbility cluster method with optional load balancer.
# If no lb group is defined installer assumes that a load balancer has
# been preconfigured. For installation the value of
# openshift_master_cluster_hostname must resolve to the load balancer
# or to one or all of the masters defined in the inventory if no load
# balancer is present.
openshift_master_cluster_method=native
openshift_master_cluster_hostname=openshift-cluster.example.com
openshift_master_cluster_public_hostname=openshift-cluster.example.com

# apply updated node defaults
openshift_node_kubelet_args={'pods-per-core': ['10'], 'max-pods': ['250'], 'image-gc-high-threshold': ['90'], 'image-gc-low-threshold': ['80']}

# override the default controller lease ttl
#osm_controller_lease_ttl=30

# enable ntp on masters to ensure proper failover
openshift_clock_enabled=true

# host group for masters
[masters]
master1.example.com
master2.example.com
master3.example.com

# host group for etcd
[etcd]
etcd1.example.com
etcd2.example.com
etcd3.example.com

# Specify load balancer host
[lb]
lb.example.com

# host group for nodes, includes region info
[nodes]
master[1:3].example.com openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"
node2.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

To use this example, modify the file to match your environment and specifications, and save it as /etc/ansible/hosts.

Multiple Masters with Master and etcd on the Same Host, and Using Native HA

The following describes an example environment for three masters with etcd on each host, one HAProxy load balancer, and two nodes using the native HA method:

Host Name
Infrastructure Component to Install

master1.example.com

Master (clustered using native HA) and node with etcd on each host

master2.example.com

master3.example.com

lb.example.com

HAProxy to load balance API master endpoints

node1.example.com

Node

node2.example.com

You can see these example hosts present in the [masters], [etcd], [lb], and [nodes] sections of the following example inventory file:

# Create an OSEv3 group that contains the master, nodes, etcd, and lb groups.
# The lb group lets Ansible configure HAProxy as the load balancing solution.
# Comment lb out if your load balancer is pre-configured.
[OSEv3:children]
masters
nodes
etcd
lb

# Set variables common for all OSEv3 hosts
[OSEv3:vars]
ansible_ssh_user=root
deployment_type=openshift-enterprise

# Uncomment the following to enable htpasswd authentication; defaults to
# DenyAllPasswordIdentityProvider.
#openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/htpasswd'}]

# Native high availbility cluster method with optional load balancer.
# If no lb group is defined installer assumes that a load balancer has
# been preconfigured. For installation the value of
# openshift_master_cluster_hostname must resolve to the load balancer
# or to one or all of the masters defined in the inventory if no load
# balancer is present.
openshift_master_cluster_method=native
openshift_master_cluster_hostname=openshift-cluster.example.com
openshift_master_cluster_public_hostname=openshift-cluster.example.com

# override the default controller lease ttl
#osm_controller_lease_ttl=30

# host group for masters
[masters]
master1.example.com
master2.example.com
master3.example.com

# host group for etcd
[etcd]
master1.example.com
master2.example.com
master3.example.com

# Specify load balancer host
[lb]
lb.example.com

# host group for nodes, includes region info
[nodes]
master[1:3].example.com openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"
node2.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

To use this example, modify the file to match your environment and specifications, and save it as /etc/ansible/hosts.

Running the Advanced Installation

After you have configured Ansible by defining an inventory file in /etc/ansible/hosts, you can run the advanced installation using the following playbook:

# ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/byo/config.yml

If for any reason the installation fails, before re-running the installer, see Known Issues to check for any specific instructions or workarounds.

Verifying the Installation

After the installation completes:

Verify that the master is started and nodes are registered and reporting in Ready status. On the master host, run the following as root:

# oc get nodes

NAME                        STATUS                     AGE
master.example.com          Ready,SchedulingDisabled   165d
node1.example.com           Ready                      165d
node2.example.com           Ready                      165d

To verify that the web console is installed correctly, use the master host name and the console port number to access the console with a web browser.

For example, for a master host with a hostname of master.openshift.com and using the default port of 8443, the web console would be found at:

https://master.openshift.com:8443/console

Now that the install has been verified, run the following command on each master and node host to add the atomic-openshift packages back to the list of yum excludes on the host:

# atomic-openshift-excluder exclude

Note

The default port for the console is 8443. If this was changed during the installation, the port can be found at openshift_master_console_port in the /etc/ansible/hosts file.

Multiple etcd Hosts

If you installed multiple etcd hosts:

On a master host, verify the etcd cluster health, substituting for the FQDNs of your etcd hosts in the following:

# etcdctl -C \
    https://etcd1.example.com:2379,https://etcd2.example.com:2379,https://etcd3.example.com:2379 \
    --ca-file=/etc/origin/master/master.etcd-ca.crt \
    --cert-file=/etc/origin/master/master.etcd-client.crt \
    --key-file=/etc/origin/master/master.etcd-client.key cluster-health

Also verify the member list is correct:

# etcdctl -C \
    https://etcd1.example.com:2379,https://etcd2.example.com:2379,https://etcd3.example.com:2379 \
    --ca-file=/etc/origin/master/master.etcd-ca.crt \
    --cert-file=/etc/origin/master/master.etcd-client.crt \
    --key-file=/etc/origin/master/master.etcd-client.key member list

Multiple Masters Using HAProxy

If you installed multiple masters using HAProxy as a load balancer, browse to the following URL according to your [lb] section definition and check HAProxy’s status:

http://<lb_hostname>:9000

You can verify your installation by consulting the HAProxy Configuration documentation.

Uninstalling OpenShift Container Platform

You can uninstall OpenShift Container Platform hosts in your cluster by running the uninstall.yml playbook. This playbook deletes OpenShift Container Platform content installed by Ansible, including:

Configuration

Containers

Default templates and image streams

Images

RPM packages

The playbook will delete content for any hosts defined in the inventory file that you specify when running the playbook. If you want to uninstall OpenShift Container Platform across all hosts in your cluster, run the playbook using the inventory file you used when installing OpenShift Container Platform initially or ran most recently:

# ansible-playbook [-i /path/to/file] \
    /usr/share/ansible/openshift-ansible/playbooks/adhoc/uninstall.yml

Uninstalling Nodes

You can also uninstall node components from specific hosts using the uninstall.yml playbook while leaving the remaining hosts and cluster alone:

Warning

This method should only be used when attempting to uninstall specific node hosts and not for specific masters or etcd hosts, which would require further configuration changes within the cluster.

First follow the steps in Deleting Nodes to remove the node object from the cluster, then continue with the remaining steps in this procedure.

Create a different inventory file that only references those hosts. For example, to only delete content from one node:

[OSEv3:children]
nodes

[OSEv3:vars]
ansible_ssh_user=root
deployment_type=openshift-enterprise

[nodes]
node3.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

Only include the sections that pertain to the hosts you are interested in uninstalling.

Only include hosts that you want to uninstall.

Specify that new inventory file using the -i option when running the uninstall.yml playbook:

# ansible-playbook -i /path/to/new/file \
    /usr/share/ansible/openshift-ansible/playbooks/adhoc/uninstall.yml

When the playbook completes, all OpenShift Container Platform content should be removed from any specified hosts.

Known Issues

The following are known issues for specified installation configurations.

Multiple Masters

On failover, it is possible for the controller manager to overcorrect, which causes the system to run more pods than what was intended. However, this is a transient event and the system does correct itself over time. See https://github.com/kubernetes/kubernetes/issues/10030 for details.

On failure of the Ansible installer, you must start from a clean operating system installation. If you are using virtual machines, start from a fresh image. If you are using bare metal machines, run the following on all hosts:

# yum -y remove openshift openshift-* etcd docker

# rm -rf /etc/origin /var/lib/openshift /etc/etcd \
    /var/lib/etcd /etc/sysconfig/atomic-openshift* /etc/sysconfig/docker* \
    /root/.kube/config /etc/ansible/facts.d /usr/share/openshift

What’s Next?

Now that you have a working OpenShift Container Platform instance, you can:

Configure authentication; by default, authentication is set to Deny All.

Deploy an integrated Docker registry.

Deploy a router.

Disconnected Installation

Overview

Frequently, portions of a datacenter may not have access to the Internet, even via proxy servers. Installing OpenShift Container Platform in these environments is considered a disconnected installation.

An OpenShift Container Platform disconnected installation differs from a regular installation in two primary ways:

The OpenShift Container Platform software channels and repositories are not available via Red Hat’s content distribution network.

OpenShift Container Platform uses several containerized components. Normally, these images are pulled directly from Red Hat’s Docker registry. In a disconnected environment, this is not possible.

A disconnected installation ensures the OpenShift Container Platform software is made available to the relevant servers, then follows the same installation process as a standard connected installation. This topic additionally details how to manually download the container images and transport them onto the relevant servers.

Once installed, in order to use OpenShift Container Platform, you will need source code in a source control repository (for example, Git). This topic assumes that an internal Git repository is available that can host source code and this repository is accessible from the OpenShift Container Platform nodes. Installing the source control repository is outside the scope of this document.

Also, when building applications in OpenShift Container Platform, your build may have some external dependencies, such as a Maven Repository or Gem files for Ruby applications. For this reason, and because they might require certain tags, many of the Quickstart templates offered by OpenShift Container Platform may not work on a disconnected environment. However, while Red Hat container images try to reach out to external repositories by default, you can configure OpenShift Container Platform to use your own internal repositories. For the purposes of this document, we assume that such internal repositories already exist and are accessible from the OpenShift Container Platform nodes hosts. Installing such repositories is outside the scope of this document.

Note

You can also have a Red Hat Satellite server that provides access to Red Hat content via an intranet or LAN. For environments with Satellite, you can synchronize the OpenShift Container Platform software onto the Satellite for use with the OpenShift Container Platform servers.

Red Hat Satellite 6.1 also introduces the ability to act as a Docker registry, and it can be used to host the OpenShift Container Platform containerized components. Doing so is outside of the scope of this document.

Prerequisites

This document assumes that you understand OpenShift Container Platform’s overall architecture and that you have already planned out what the topology of your environment will look like.

Required Software and Components

In order to pull down the required software repositories and container images, you will need a Red Hat Enterprise Linux (RHEL) 7 server with access to the Internet and at least 100GB of additional free space. All steps in this section should be performed on the Internet-connected server as the root system user.

Syncing Repositories

Before you sync with the required repositories, you may need to import the appropriate GPG key:

# rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

If the key is not imported, the indicated package is deleted after syncing the repository.

To sync the required repositories:

Register the server with the Red Hat Customer Portal. You must use the login and password associated with the account that has access to the OpenShift Container Platform subscriptions:

# subscription-manager register

Attach to a subscription that provides OpenShift Container Platform channels. You can find the list of available subscriptions using:

# subscription-manager list --available --matches '*OpenShift*'

Then, find the pool ID for the subscription that provides OpenShift Container Platform, and attach it:

# subscription-manager attach --pool=<pool_id>
# subscription-manager repos --disable="*"
# subscription-manager repos \
    --enable="rhel-7-server-rpms" \
    --enable="rhel-7-server-extras-rpms" \
    --enable="rhel-7-server-ose-3.3-rpms"

The yum-utils command provides the reposync utility, which lets you mirror yum repositories, and createrepo can create a usable yum repository from a directory:

# yum -y install yum-utils createrepo docker git

You will need up to 110GB of free space in order to sync the software. Depending on how restrictive your organization’s policies are, you could re-connect this server to the disconnected LAN and use it as the repository server. You could use USB-connected storage and transport the software to another server that will act as the repository server. This topic covers these options.

Make a path to where you want to sync the software (either locally or on your USB or other device):

# mkdir -p </path/to/repos>

Sync the packages and create the repository for each of them. You will need to modify the command for the appropriate path you created above:

# for repo in \
rhel-7-server-rpms rhel-7-server-extras-rpms \
rhel-7-server-ose-3.3-rpms
do
  reposync --gpgcheck -lm --repoid=${repo} --download_path=/path/to/repos
  createrepo -v </path/to/repos/>${repo} -o </path/to/repos/>${repo}
done

Syncing Images

To sync the container images:

Start the Docker daemon:

# systemctl start docker

Pull all of the required OpenShift Container Platform containerized components. Replace <tag> with v3.3.1.11 for the latest version.

# docker pull registry.access.redhat.com/openshift3/ose-haproxy-router:<tag>
# docker pull registry.access.redhat.com/openshift3/ose-deployer:<tag>
# docker pull registry.access.redhat.com/openshift3/ose-sti-builder:<tag>
# docker pull registry.access.redhat.com/openshift3/ose-docker-builder:<tag>
# docker pull registry.access.redhat.com/openshift3/ose-pod:<tag>
# docker pull registry.access.redhat.com/openshift3/ose-docker-registry:<tag>

Pull all of the required OpenShift Container Platform containerized components for the additional centralized log aggregation and metrics aggregation components. Replace <tag> with 3.3.1 for the latest version.

# docker pull registry.access.redhat.com/openshift3/logging-deployer:<tag>
# docker pull registry.access.redhat.com/openshift3/logging-elasticsearch:<tag>
# docker pull registry.access.redhat.com/openshift3/logging-kibana:<tag>
# docker pull registry.access.redhat.com/openshift3/logging-fluentd:<tag>
# docker pull registry.access.redhat.com/openshift3/logging-curator:<tag>
# docker pull registry.access.redhat.com/openshift3/logging-auth-proxy:<tag>
# docker pull registry.access.redhat.com/openshift3/metrics-deployer:<tag>
# docker pull registry.access.redhat.com/openshift3/metrics-hawkular-metrics:<tag>
# docker pull registry.access.redhat.com/openshift3/metrics-cassandra:<tag>
# docker pull registry.access.redhat.com/openshift3/metrics-heapster:<tag>

Pull the Red Hat-certified Source-to-Image (S2I) builder images that you intend to use in your OpenShift environment. You can pull the following images:

jboss-eap70-openshift

jboss-amq-62

jboss-datagrid65-openshift

jboss-decisionserver62-openshift

jboss-eap64-openshift

jboss-eap70-openshift

jboss-webserver30-tomcat7-openshift

jboss-webserver30-tomcat8-openshift

mongodb

mysql

nodejs

perl

php

postgresql

python

redhat-sso70-openshift

ruby

Make sure to indicate the correct tag specifying the desired version number. For example, to pull both the previous and latest version of the Tomcat image:

# docker pull \
registry.access.redhat.com/jboss-webserver-3/webserver30-tomcat7-openshift:latest
# docker pull \
registry.access.redhat.com/jboss-webserver-3/webserver30-tomcat7-openshift:1.1

Preparing Images for Export

Container images can be exported from a system by first saving them to a tarball and then transporting them:

Make and change into a repository home directory:

# mkdir </path/to/repos/images>
# cd </path/to/repos/images>

Export the OpenShift Container Platform containerized components:

# docker save -o ose3-images.tar \
    registry.access.redhat.com/openshift3/ose-haproxy-router \
    registry.access.redhat.com/openshift3/ose-deployer \
    registry.access.redhat.com/openshift3/ose-sti-builder \
    registry.access.redhat.com/openshift3/ose-docker-builder \
    registry.access.redhat.com/openshift3/ose-pod \
    registry.access.redhat.com/openshift3/ose-docker-registry

If you synchronized the metrics and log aggregation images, export:

# docker save -o ose3-logging-metrics-images.tar \
    registry.access.redhat.com/openshift3/logging-deployer \
    registry.access.redhat.com/openshift3/logging-elasticsearch \
    registry.access.redhat.com/openshift3/logging-kibana \
    registry.access.redhat.com/openshift3/logging-fluentd \
    registry.access.redhat.com/openshift3/logging-auth-proxy \
    registry.access.redhat.com/openshift3/metrics-deployer \
    registry.access.redhat.com/openshift3/metrics-hawkular-metrics \
    registry.access.redhat.com/openshift3/metrics-cassandra \
    registry.access.redhat.com/openshift3/metrics-heapster

Export the S2I builder images that you synced in the previous section. For example, if you synced only the Tomcat image:

# docker save -o ose3-builder-images.tar \
    registry.access.redhat.com/jboss-webserver-3/webserver30-tomcat7-openshift:latest \
    registry.access.redhat.com/jboss-webserver-3/webserver30-tomcat7-openshift:1.1

Repository Server

During the installation (and for later updates, should you so choose), you will need a webserver to host the repositories. RHEL 7 can provide the Apache webserver.

Option 1: Re-configuring as a Web server

If you can re-connect the server where you synchronized the software and images to your LAN, then you can simply install Apache on the server:

# yum install httpd

Skip to Placing the Software.

Option 2: Building a Repository Server

If you need to build a separate server to act as the repository server, install a new RHEL 7 system with at least 110GB of space. On this repository server during the installation, make sure you select the Basic Web Server option.

Placing the Software

If necessary, attach the external storage, and then copy the repository files into Apache’s root folder. Note that the below copy step (cp -a) should be substituted with move (mv) if you are repurposing the server you used to sync:

# cp -a /path/to/repos /var/www/html/
# chmod -R +r /var/www/html/repos
# restorecon -vR /var/www/html

Add the firewall rules:

# firewall-cmd --permanent --add-service=http
# firewall-cmd --reload

Enable and start Apache for the changes to take effect:

# systemctl enable httpd
# systemctl start httpd

OpenShift Container Platform Systems

Building Your Hosts

At this point you can perform the initial creation of the hosts that will be part of the OpenShift Container Platform environment. It is recommended to use the latest version of RHEL 7 and to perform a minimal installation. You will also want to pay attention to the other OpenShift Container Platform-specific prerequisites.

Once the hosts are initially built, the repositories can be set up.

Connecting the Repositories

On all of the relevant systems that will need OpenShift Container Platform software components, create the required repository definitions. Place the following text in the /etc/yum.repos.d/ose.repo file, replacing <server_IP> with the IP or host name of the Apache server hosting the software repositories:

[rhel-7-server-rpms]
name=rhel-7-server-rpms
baseurl=http://<server_IP>/repos/rhel-7-server-rpms
enabled=1
gpgcheck=0
[rhel-7-server-extras-rpms]
name=rhel-7-server-extras-rpms
baseurl=http://<server_IP>/repos/rhel-7-server-extras-rpms
enabled=1
gpgcheck=0
[rhel-7-server-ose-3.3-rpms]
name=rhel-7-server-ose-3.3-rpms
baseurl=http://<server_IP>/repos/rhel-7-server-ose-3.3-rpms
enabled=1
gpgcheck=0

Host Preparation

At this point, the systems are ready to continue to be prepared following the OpenShift Container Platform documentation.

Skip the section titled Host Registration and start with Installing Base Packages.

Installing OpenShift Container Platform

Importing OpenShift Container Platform Containerized Components

To import the relevant components, securely copy the images from the connected host to the individual OpenShift Container Platform hosts:

# scp /var/www/html/repos/images/ose3-images.tar root@<openshift_host_name>:
# ssh root@<openshift_host_name> "docker load -i ose3-images.tar"

If you prefer, you could use wget on each OpenShift Container Platform host to fetch the tar file, and then perform the Docker import command locally. Perform the same steps for the metrics and logging images, if you synchronized them.

On the host that will act as an OpenShift Container Platform master, copy and import the builder images:

# scp /var/www/html/images/ose3-builder-images.tar root@<openshift_master_host_name>:
# ssh root@<openshift_master_host_name> "docker load -i ose3-builder-images.tar"

Running the OpenShift Container Platform Installer

You can now choose to follow the quick or advanced OpenShift Container Platform installation instructions in the documentation.

Creating the Internal Docker Registry

You now need to create the internal Docker registry.

Post-Installation Changes

In one of the previous steps, the S2I images were imported into the Docker daemon running on one of the OpenShift Container Platform master hosts. In a connected installation, these images would be pulled from Red Hat’s registry on demand. Since the Internet is not available to do this, the images must be made available in another Docker registry.

OpenShift Container Platform provides an internal registry for storing the images that are built as a result of the S2I process, but it can also be used to hold the S2I builder images. The following steps assume you did not customize the service IP subnet (172.30.0.0/16) or the Docker registry port (5000).

Re-tagging S2I Builder Images

On the master host where you imported the S2I builder images, obtain the service address of your Docker registry that you installed on the master:

# export REGISTRY=$(oc get service docker-registry -t '{{.spec.clusterIP}}{{"\n"}}')

Next, tag all of the builder images that you synced and exported before pushing them into the OpenShift Container Platform Docker registry. For example, if you synced and exported only the Tomcat image:

# docker tag \
registry.access.redhat.com/jboss-webserver-3/webserver30-tomcat7-openshift:1.1 \
$REGISTRY:5000/openshift/webserver30-tomcat7-openshift:1.1
# docker tag \
registry.access.redhat.com/jboss-webserver-3/webserver30-tomcat7-openshift:latest \
$REGISTRY:5000/openshift/webserver30-tomcat7-openshift:1.2
# docker tag \
registry.access.redhat.com/jboss-webserver-3/webserver30-tomcat7-openshift:latest \
$REGISTRY:5000/openshift/webserver30-tomcat7-openshift:latest

Creating an Administrative User

Pushing the container images into OpenShift Container Platform’s Docker registry requires a user with cluster-admin privileges. Because the default OpenShift Container Platform system administrator does not have a standard authorization token, they cannot be used to log in to the Docker registry.

To create an administrative user:

Create a new user account in the authentication system you are using with OpenShift Container Platform. For example, if you are using local htpasswd-based authentication:

# htpasswd -b /etc/openshift/openshift-passwd <admin_username> <password>

The external authentication system now has a user account, but a user must log in to OpenShift Container Platform before an account is created in the internal database. Log in to OpenShift Container Platform for this account to be created. This assumes you are using the self-signed certificates generated by OpenShift Container Platform during the installation:

# oc login --certificate-authority=/etc/origin/master/ca.crt \
    -u <admin_username> https://<openshift_master_host>:8443

Get the user’s authentication token:

# MYTOKEN=$(oc whoami -t)
# echo $MYTOKEN
iwo7hc4XilD2KOLL4V1O55ExH2VlPmLD-W2-JOd6Fko

Modifying the Security Policies

Using oc login switches to the new user. Switch back to the OpenShift Container Platform system administrator in order to make policy changes:

# oc login -u system:admin

In order to push images into the OpenShift Container Platform Docker registry, an account must have the image-builder security role. Add this to your OpenShift Container Platform administrative user:

# oadm policy add-role-to-user system:image-builder <admin_username>

Next, add the administrative role to the user in the openshift project. This allows the administrative user to edit the openshift project, and, in this case, push the container images:

# oadm policy add-role-to-user admin <admin_username> -n openshift

Editing the Image Stream Definitions

The openshift project is where all of the image streams for builder images are created by the installer. They are loaded by the installer from the /usr/share/openshift/examples directory. Change all of the definitions by deleting the image streams which had been loaded into OpenShift Container Platform’s database, then re-create them:

Delete the existing image streams:

# oc delete is -n openshift --all

Make a backup of the files in /usr/share/openshift/examples/ if you desire. Next, edit the file image-streams-rhel7.json in the /usr/share/openshift/examples/image-streams folder. You will find an image stream section for each of the builder images. Edit the spec stanza to point to your internal Docker registry.

For example, change:

"spec": {
  "dockerImageRepository": "registry.access.redhat.com/rhscl/mongodb-26-rhel7",

to:

"spec": {
  "dockerImageRepository": "172.30.69.44:5000/openshift/mongodb-26-rhel7",

In the above, the repository name was changed from rhscl to openshift. You will need to ensure the change, regardless of whether the repository is rhscl, openshift3, or another directory. Every definition should have the following format:

<registry_ip>:5000/openshift/<image_name>

Repeat this change for every image stream in the file. Ensure you use the correct IP address that you determined earlier. When you are finished, save and exit. Repeat the same process for the JBoss image streams in the /usr/share/openshift/examples/xpaas-streams/jboss-image-streams.json file.

Load the updated image stream definitions:

# oc create -f /usr/share/openshift/examples/image-streams/image-streams-rhel7.json -n openshift
# oc create -f /usr/share/openshift/examples/xpaas-streams/jboss-image-streams.json -n openshift

Loading the Container Images

At this point the system is ready to load the container images.

Log in to the Docker registry using the token and registry service IP obtained earlier:

# docker login -u adminuser -e mailto:adminuser@abc.com \
   -p $MYTOKEN $REGISTRY:5000

Push the Docker images:

# docker push $REGISTRY:5000/openshift/webserver30-tomcat7-openshift:1.1
# docker push $REGISTRY:5000/openshift/webserver30-tomcat7-openshift:1.2
# docker push $REGISTRY:5000/openshift/webserver30-tomcat7-openshift:latest

Verify that all the image streams now have the tags populated:

# oc get imagestreams -n openshift
NAME                                 DOCKER REPO                                                      TAGS                                     UPDATED
jboss-webserver30-tomcat7-openshift  $REGISTRY/jboss-webserver-3/webserver30-jboss-tomcat7-openshift  1.1,1.1-2,1.1-6 + 2 more...              2 weeks ago
...

Installing a Router

At this point, the OpenShift Container Platform environment is almost ready for use. It is likely that you will want to install and configure a router.

Installing a Stand-alone Registry

Overview

OpenShift Container Platform is a fully-featured platform-as-a-service (PaaS) enterprise solution that includes an embedded container registry. However, it can alternatively be installed as a stand-alone container registry to run on-premise or in the cloud.

The stand-alone registry from OpenShift Container Platform provides the following capabilities:

A user-focused registry web console.

Secured traffic by default, served via TLS.

Global identity provider authentication.

A project namespace model to enable teams to collaborate through role-based access control (RBAC) authorization.

A Kubernetes-based cluster to manage services.

An image abstraction called image streams to enhance image management.

Minimum Hardware Requirements

Installing OpenShift Container Platform as a stand-alone registry has the following hardware requirements:

Physical or virtual system, or an instance running on a public or private IaaS.

Base OS: RHEL 7.1 or later with "Minimal" installation option, or RHEL Atomic Host 7.2.6 or later.

NetworkManager 1.0 or later

2 vCPU.

Minimum 16 GB RAM.

Minimum 15 GB hard disk space for the file system containing /var/.

An additional minimum 15 GB unallocated space to be used for Docker’s storage back end; see Configuring Docker Storage for details.

Important

OpenShift Container Platform only supports servers with x86_64 architecture.

Note

Meeting the /var/ file system sizing requirements in RHEL Atomic Host requires making changes to the default configuration. See Managing Storage in Red Hat Enterprise Linux Atomic Host for instructions on configuring this during or after installation.

Supported System Topologies

The following system topologies are supported when running OpenShift Container Platform as a stand-alone registry:

All-in-one

A single host that includes the master, node, etcd, and registry components.

Multiple Masters (Highly-Available)

Three hosts with all components included on each (master, node, etcd, and registry), with the masters configured for native high-availability.

Host Preparation

Before installing a stand-alone registry, all of the same steps detailed in the Host Preparation topic for installing a full OpenShift Container Platform PaaS must be performed. This includes registering and subscribing the host(s) to the proper repositories, installing or updating certain packages, and setting up Docker and its storage requirements.

Follow the steps in the Host Preparation topic, then continue to Installation Methods.

Installation Methods

To install a stand-alone registry, use either of the standard installation methods (quick or advanced) used to install any variant of OpenShift Container Platform.

Quick Installation for Stand-alone Registries

When using the quick installation method to install a stand-alone registry, start the interactive installation by running:

$ atomic-openshift-installer install

Then follow the on-screen instructions to install a new registry. The installation questions will be largely the same as if you were installing a full OpenShift Container Platform PaaS, but when you reach the following screen:

Which variant would you like to install?

(1) OpenShift Container Platform 3.3
(2) Registry 3.3

Be sure to choose 2 to follow the registry installation path.

Note

For further usage details on the quick installer in general, see the full topic at Quick Installation.

Advanced Installation for Stand-alone Registries

When using the advanced installation method to install a stand-alone registry, use the same steps for installing a full OpenShift Container Platform PaaS using Ansible described in the full Advanced Installation topic. The main difference is that you must set deployment_subtype=registry in the inventory file within the [OSEv3:vars] section for the playbooks to follow the registry installation path.

See the following example inventory files for the different supported system topologies:

Example 2.5. All-in-one Stand-alone Registry Inventory File

# Create an OSEv3 group that contains the masters and nodes groups
[OSEv3:children]
masters
nodes

# Set variables common for all OSEv3 hosts
[OSEv3:vars]
# SSH user, this user should allow ssh based auth without requiring a password
ansible_ssh_user=root

# If ansible_ssh_user is not root, ansible_become must be set to true
#ansible_become=true

deployment_type=openshift-enterprise
deployment_subtype=registry

# uncomment the following to enable htpasswd authentication; defaults to DenyAllPasswordIdentityProvider
#openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/htpasswd'}]

# host group for masters
[masters]
registry.example.com

# host group for nodes, includes region info
[nodes]
registry.example.com openshift_schedulable=true openshift_node_labels="{'region': 'infra', 'zone': 'default'}"

Set deployment_subtype=registry to ensure installation of the stand-alone registry.

Set openshift_schedulable=true on the node entry to make the single node schedulable for pod placement.

Example 2.6. Multiple Masters (Highly-Available) Stand-alone Registry Inventory File

# Create an OSEv3 group that contains the master, nodes, etcd, and lb groups.
# The lb group lets Ansible configure HAProxy as the load balancing solution.
# Comment lb out if your load balancer is pre-configured.
[OSEv3:children]
masters
nodes
etcd
lb

# Set variables common for all OSEv3 hosts
[OSEv3:vars]
ansible_ssh_user=root
deployment_type=openshift-enterprise
deployment_subtype=registry

# Uncomment the following to enable htpasswd authentication; defaults to
# DenyAllPasswordIdentityProvider.
#openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/htpasswd'}]

# Native high availability cluster method with optional load balancer.
# If no lb group is defined installer assumes that a load balancer has
# been preconfigured. For installation the value of
# openshift_master_cluster_hostname must resolve to the load balancer
# or to one or all of the masters defined in the inventory if no load
# balancer is present.
openshift_master_cluster_method=native
openshift_master_cluster_hostname=openshift-cluster.example.com
openshift_master_cluster_public_hostname=openshift-cluster.example.com

# apply updated node defaults
openshift_node_kubelet_args={'pods-per-core': ['10'], 'max-pods': ['250'], 'image-gc-high-threshold': ['90'], 'image-gc-low-threshold': ['80']}

# override the default controller lease ttl
#osm_controller_lease_ttl=30

# enable ntp on masters to ensure proper failover
openshift_clock_enabled=true

# host group for masters
[masters]
master1.example.com
master2.example.com
master3.example.com

# host group for etcd
[etcd]
etcd1.example.com
etcd2.example.com
etcd3.example.com

# Specify load balancer host
[lb]
lb.example.com

# host group for nodes, includes region info
[nodes]
master[1:3].example.com openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"
node2.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

Setting deployment_subtype=registry ensures installation of the stand-alone registry.

After you have configured Ansible by defining an inventory file in /etc/ansible/hosts, you can run the advanced installation using the following playbook:

# ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/byo/config.yml

Note

For more detailed usage information on the advanced installation method, including a comprehensive list of available Ansible variables, see the full topic at Advanced Installation.

Chapter 3. Setting up the Registry

Registry Overview

About the Registry

OpenShift Container Platform can build container images from your source code, deploy them, and manage their lifecycle. To enable this, OpenShift Container Platform provides an internal, integrated Docker registry that can be deployed in your OpenShift Container Platform environment to locally manage images.

Integrated or Stand-alone Registries

During an initial installation of a full OpenShift Container Platform cluster, it is likely that the registry was deployed automatically during the installation process. If it was not, or if you want to further customize the configuration of your registry, see Deploying a Registry on Existing Clusters.

While it can be deployed to run as an integrated part of your full OpenShift Container Platform cluster, the OpenShift Container Platform registry can alternatively be installed separately as a stand-alone container image registry.

To install a stand-alone registry, follow Installing a Stand-alone Registry. This installation path deploys an all-in-one cluster running a registry and specialized web console.

Deploying a Registry on Existing Clusters

Overview

If the integrated registry was not previously deployed automatically during the initial installation of your OpenShift Container Platform cluster, or if it is no longer running successfully and you need to redeploy it on your existing cluster, see the following sections for options on deploying a new registry.

Note

This topic is not required if you installed a stand-alone registry.

Deploying the Registry

To deploy the integrated Docker registry, use the oadm registry command as a user with cluster administrator privileges. For example:

$ oadm registry --config=/etc/origin/master/admin.kubeconfig \
    --service-account=registry \
    --images='registry.access.redhat.com/openshift3/ose-${component}:${version}'

--config is the path to the CLI configuration file for the cluster administrator.

--service-account is the service account used to run the registry’s pod.

Required to pull the correct image for OpenShift Container Platform.

This creates a service and a deployment configuration, both called docker-registry. Once deployed successfully, a pod is created with a name similar to docker-registry-1-cpty9.

To see a full list of options that you can specify when creating the registry:

$ oadm registry --help

Deploying the Registry as a DaemonSet

Use the oadm registry command to deploy the registry as a DaemonSet with the --daemonset option.

Daemonsets ensure that when nodes are created, they contain copies of a specified pod. When the nodes are removed, the pods are garbage collected.

For more information on DaemonSets, see the DaemonSet documentation.

Note

Using DaemonSets with OpenShift Container Platform is a work in progress, and the only supported process is creating a registry. Currently, using deployment configurations to deploy a registry is recommended.

Registry Compute Resources

By default, the registry is created with no settings for compute resource requests or limits. For production, it is highly recommended that the deployment configuration for the registry be updated to set resource requests and limits for the registry pod. Otherwise, the registry pod will be considered a BestEffort pod.

See Compute Resources for more information on configuring requests and limits.

Storage for the Registry

The registry stores container images and metadata. If you simply deploy a pod with the registry, it uses an ephemeral volume that is destroyed if the pod exits. Any images anyone has built or pushed into the registry would disappear.

Production Use

For production use, attach a remote volume or define and use the persistent storage method of your choice.

For example, to use an existing persistent volume claim:

$ oc volume deploymentconfigs/docker-registry --add --name=registry-storage -t pvc \
     --claim-name=<pvc_name> --overwrite

Note

See Known Issues if using a scaled registry with a shared NFS volume.

Use Amazon S3 as a Storage Back-end

There is also an option to use Amazon Simple Storage Service storage with the internal Docker registry. It is a secure cloud storage manageable through AWS Management Console. To use it, the registry’s configuration file must be manually edited and mounted to the registry pod. However, before you start with the configuration, look at upstream’s recommended steps.

Take a default YAML configuration file as a base and replace the filesystem entry in the storage section with s3 entry such as below. The resulting storage section may look like this:

storage:
  cache:
    layerinfo: inmemory
  delete:
    enabled: true
  s3:
    accesskey: awsaccesskey
    secretkey: awssecretkey
    region: us-west-1
    regionendpoint: http://myobjects.local
    bucket: bucketname
    encrypt: true
    keyid: mykeyid
    secure: true
    v4auth: false
    chunksize: 5242880
    rootdirectory: /s3/object/name/prefix

All of the s3 configuration options are documented in upstream’s driver reference documentation.

Overriding the registry configuration will take you through the additional steps on mounting the configuration file into pod.

Warning

When the registry runs on the S3 storage back-end, there are reported issues.

Non-Production Use

For non-production use, you can use the --mount-host=<path> option to specify a directory for the registry to use for persistent storage. The registry volume is then created as a host-mount at the specified <path>.

Important

The --mount-host option mounts a directory from the node on which the registry container lives. If you scale up the docker-registry deployment configuration, it is possible that your registry pods and containers will run on different nodes, which can result in two or more registry containers, each with its own local storage. This will lead to unpredictable behavior, as subsequent requests to pull the same image repeatedly may not always succeed, depending on which container the request ultimately goes to.

The --mount-host option requires that the registry container run in privileged mode. This is automatically enabled when you specify --mount-host. However, not all pods are allowed to run privileged containers by default. If you still want to use this option, create the registry and specify that it use the registry service account that was created during installation:

$ oadm registry --service-account=registry \
    --config=/etc/origin/master/admin.kubeconfig \
    --images='registry.access.redhat.com/openshift3/ose-${component}:${version}' \
    --mount-host=<path>

Important

The Docker registry pod runs as user 1001. This user must be able to write to the host directory. You may need to change directory ownership to user ID 1001 with this command:

$ sudo chown 1001:root <path>

Enabling the Registry Console

OpenShift Container Platform provides a web-based interface to the integrated registry. This registry console is an optional component for browsing and managing images. It is deployed as a stateless service running as a pod.

Note

If you installed OpenShift Container Platform as a stand-alone registry, the registry console is already deployed and secured automatically during installation.

Important

If Cockpit is already running, you’ll need to shut it down before proceeding in order to avoid a port conflict (9090 by default) with the registry console.

Deploying the Registry Console

Important

You must first have exposed the registry.

Create a passthrough route in the default project. You will need this when creating the registry console application in the next step.

$ oc create route passthrough --service registry-console \
    --port registry-console \
    -n default

Deploy the registry console application. Replace <openshift_oauth_url> with the URL of the OpenShift Container Platform OAuth provider, which is typically the master.

$ oc new-app -n default --template=registry-console -p \
           OPENSHIFT_OAUTH_PROVIDER_URL="https://<openshift_oauth_url>:8443",REGISTRY_HOST=$(oc get route docker-registry -n default --template='{{ .spec.host }}'),COCKPIT_KUBE_URL=$(oc get route registry-console -n default --template='https://{{ .spec.host }}')

Note

If the redirection URL is wrong when you are trying to log in to the registry console, check your OAuth client with oc get oauthclients.

Finally, use a web browser to view the console using the route URI.

Securing the Registry Console

By default, the registry console generates self-signed TLS certificates if deployed manually per the steps in Deploying the Registry Console. See Troubleshooting the Registry Console for more information.

Use the following steps to add your organization’s signed certificates as a secret volume. This assumes your certificates are available on the the oc client host.

Create a .cert file containing the certificate and key. Format the file with:

One or more BEGIN CERTIFICATE blocks for the server certificate and the intermediate certificate authorities

A block containing a BEGIN PRIVATE KEY or similar for the key. The key must not be encrypted

For example:

-----BEGIN CERTIFICATE-----
MIIDUzCCAjugAwIBAgIJAPXW+CuNYS6QMA0GCSqGSIb3DQEBCwUAMD8xKTAnBgNV
BAoMIGI0OGE2NGNkNmMwNTQ1YThhZTgxOTEzZDE5YmJjMmRjMRIwEAYDVQQDDAls
...
-----END CERTIFICATE-----
-----BEGIN CERTIFICATE-----
MIIDUzCCAjugAwIBAgIJAPXW+CuNYS6QMA0GCSqGSIb3DQEBCwUAMD8xKTAnBgNV
BAoMIGI0OGE2NGNkNmMwNTQ1YThhZTgxOTEzZDE5YmJjMmRjMRIwEAYDVQQDDAls
...
-----END CERTIFICATE-----
-----BEGIN PRIVATE KEY-----
MIIEvgIBADANBgkqhkiG9w0BAQEFAASCBKgwggSkAgEAAoIBAQCyOJ5garOYw0sm
8TBCDSqQ/H1awGMzDYdB11xuHHsxYS2VepPMzMzryHR137I4dGFLhvdTvJUH8lUS
...
-----END PRIVATE KEY-----

The registry console loads a certificate from the /etc/cockpit/ws-certs.d directory. It uses the last file with a .cert extension in alphabetical order. Therefore, the .cert file should contain at least two PEM blocks formatted in the OpenSSL style.

If no certificate is found, a self-signed certificate is created using the openssl command and stored in the 0-self-signed.cert file.

Create the secret:

$ oc secrets new console-secret \
    /path/to/console.cert

Add the secrets to the registry-console deployment configuration:

$ oc volume dc/registry-console --add --type=secret \
    --secret-name=console-secret -m /etc/cockpit/ws-certs.d

This triggers a new deployment of the registry console to include your signed certificates.

Troubleshooting the Registry Console

Debug Mode

The registry console debug mode is enabled using an environment variable. The following command redeploys the registry console in debug mode:

$ oc set env dc registry-console G_MESSAGES_DEBUG=cockpit-ws,cockpit-wrapper

Enabling debug mode allows more verbose logging to appear in the registry console’s pod logs.

Display SSL Certificate Path

To check which certificate the registry console is using, a command can be run from inside the console pod.

List the pods in the default project and find the registry console’s pod name:

$ oc get pods -n default
NAME                       READY     STATUS    RESTARTS   AGE
registry-console-1-rssrw   1/1       Running   0          1d

Using the pod name from the previous command, get the certificate path that the cockpit-ws process is using. This example shows the console using the auto-generated certificate:

$ oc exec registry-console-1-rssrw remotectl certificate
certificate: /etc/cockpit/ws-certs.d/0-self-signed.cert

Accessing the Registry

Viewing Logs

To view the logs for the Docker registry, use the oc logs command with the deployment config:

$ oc logs dc/docker-registry
2015-05-01T19:48:36.300593110Z time="2015-05-01T19:48:36Z" level=info msg="version=v2.0.0+unknown"
2015-05-01T19:48:36.303294724Z time="2015-05-01T19:48:36Z" level=info msg="redis not configured" instance.id=9ed6c43d-23ee-453f-9a4b-031fea646002
2015-05-01T19:48:36.303422845Z time="2015-05-01T19:48:36Z" level=info msg="using inmemory layerinfo cache" instance.id=9ed6c43d-23ee-453f-9a4b-031fea646002
2015-05-01T19:48:36.303433991Z time="2015-05-01T19:48:36Z" level=info msg="Using OpenShift Auth handler"
2015-05-01T19:48:36.303439084Z time="2015-05-01T19:48:36Z" level=info msg="listening on :5000" instance.id=9ed6c43d-23ee-453f-9a4b-031fea646002

File Storage

Tag and image metadata is stored in OpenShift Container Platform, but the registry stores layer and signature data in a volume that is mounted into the registry container at /registry. As oc exec does not work on privileged containers, to view a registry’s contents you must manually SSH into the node housing the registry pod’s container, then run docker exec on the container itself:

List the current pods to find the pod name of your Docker registry:

# oc get pods

Then, use oc describe to find the host name for the node running the container:

# oc describe pod <pod_name>

Log into the desired node:

# ssh node.example.com

List the running containers on the node host and identify the container ID for the Docker registry:

# docker ps | grep ose-docker-registry

List the registry contents using the docker exec command:

# docker exec -it 4c01db0b339c find /registry
/registry/docker
/registry/docker/registry
/registry/docker/registry/v2
/registry/docker/registry/v2/blobs
/registry/docker/registry/v2/blobs/sha256
/registry/docker/registry/v2/blobs/sha256/ed
/registry/docker/registry/v2/blobs/sha256/ed/ede17b139a271d6b1331ca3d83c648c24f92cece5f89d95ac6c34ce751111810
/registry/docker/registry/v2/blobs/sha256/ed/ede17b139a271d6b1331ca3d83c648c24f92cece5f89d95ac6c34ce751111810/data
/registry/docker/registry/v2/blobs/sha256/a3
/registry/docker/registry/v2/blobs/sha256/a3/a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4
/registry/docker/registry/v2/blobs/sha256/a3/a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4/data
/registry/docker/registry/v2/blobs/sha256/f7
/registry/docker/registry/v2/blobs/sha256/f7/f72a00a23f01987b42cb26f259582bb33502bdb0fcf5011e03c60577c4284845
/registry/docker/registry/v2/blobs/sha256/f7/f72a00a23f01987b42cb26f259582bb33502bdb0fcf5011e03c60577c4284845/data
/registry/docker/registry/v2/repositories
/registry/docker/registry/v2/repositories/p1
/registry/docker/registry/v2/repositories/p1/pause
/registry/docker/registry/v2/repositories/p1/pause/_manifests
/registry/docker/registry/v2/repositories/p1/pause/_manifests/revisions
/registry/docker/registry/v2/repositories/p1/pause/_manifests/revisions/sha256
/registry/docker/registry/v2/repositories/p1/pause/_manifests/revisions/sha256/e9a2ac6418981897b399d3709f1b4a6d2723cd38a4909215ce2752a5c068b1cf
/registry/docker/registry/v2/repositories/p1/pause/_manifests/revisions/sha256/e9a2ac6418981897b399d3709f1b4a6d2723cd38a4909215ce2752a5c068b1cf/signatures
/registry/docker/registry/v2/repositories/p1/pause/_manifests/revisions/sha256/e9a2ac6418981897b399d3709f1b4a6d2723cd38a4909215ce2752a5c068b1cf/signatures/sha256
/registry/docker/registry/v2/repositories/p1/pause/_manifests/revisions/sha256/e9a2ac6418981897b399d3709f1b4a6d2723cd38a4909215ce2752a5c068b1cf/signatures/sha256/ede17b139a271d6b1331ca3d83c648c24f92cece5f89d95ac6c34ce751111810
/registry/docker/registry/v2/repositories/p1/pause/_manifests/revisions/sha256/e9a2ac6418981897b399d3709f1b4a6d2723cd38a4909215ce2752a5c068b1cf/signatures/sha256/ede17b139a271d6b1331ca3d83c648c24f92cece5f89d95ac6c34ce751111810/link
/registry/docker/registry/v2/repositories/p1/pause/_uploads
/registry/docker/registry/v2/repositories/p1/pause/_layers
/registry/docker/registry/v2/repositories/p1/pause/_layers/sha256
/registry/docker/registry/v2/repositories/p1/pause/_layers/sha256/a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4
/registry/docker/registry/v2/repositories/p1/pause/_layers/sha256/a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4/link
/registry/docker/registry/v2/repositories/p1/pause/_layers/sha256/f72a00a23f01987b42cb26f259582bb33502bdb0fcf5011e03c60577c4284845
/registry/docker/registry/v2/repositories/p1/pause/_layers/sha256/f72a00a23f01987b42cb26f259582bb33502bdb0fcf5011e03c60577c4284845/link

This directory stores all layers and signatures as blobs.

This file contains the blob’s contents.

This directory stores all the image repositories.

This directory is for a single image repository p1/pause.

This directory contains signatures for a particular image manifest revision.

This file contains a reference back to a blob (which contains the signature data).

This directory contains any layers that are currently being uploaded and staged for the given repository.

This directory contains links to all the layers this repository references.

This file contains a reference to a specific layer that has been linked into this repository via an image.

Accessing the Registry Directly

For advanced usage, you can access the registry directly to invoke docker commands. This allows you to push images to or pull them from the integrated registry directly using operations like docker push or docker pull. To do so, you must be logged in to the registry using the docker login command. The operations you can perform depend on your user permissions, as described in the following sections.

User Prerequisites

To access the registry directly, the user that you use must satisfy the following, depending on your intended usage:

For any direct access, you must have a regular user, if one does not already exist, for your preferred identity provider. A regular user can generate an access token required for logging in to the registry. System users, such as system:admin, cannot obtain access tokens and, therefore, cannot access the registry directly.

For example, if you are using HTPASSWD authentication, you can create one using the following command:

# htpasswd /etc/origin/openshift-htpasswd <user_name>

The user must have the system:registry role. To add this role:

# oadm policy add-role-to-user system:registry <user_name>

Have the admin role for the project associated with the Docker operation. For example, if accessing images in the global openshift project:

 $ oadm policy add-role-to-user admin <user_name> -n openshift

For writing or pushing images, for example when using the docker push command, the user must have the system:image-builder role. To add this role:

$ oadm policy add-role-to-user system:image-builder <user_name>

For more information on user permissions, see Managing Role Bindings.

Logging in to the Registry

Note

Ensure your user satisfies the prerequisites for accessing the registry directly.

To log in to the registry directly:

Ensure you are logged in to OpenShift Container Platform as a regular user:

$ oc login

Get your access token:

$ oc whoami -t

Log in to the Docker registry:

$ docker login -u <username> -e <any_email_address> \
    -p <token_value> <registry_ip>:<port>

Pushing and Pulling Images

After logging in to the registry, you can perform docker pull and docker push operations against your registry.

Important

You can pull arbitrary images, but if you have the system:registry role added, you can only push images to the registry in your project.

In the following examples, we use:

Component

Value

<registry_ip>

172.30.124.220

<port>

5000

<project>

openshift

<image>

busybox

<tag>

omitted (defaults to latest)

Pull an arbitrary image:

$ docker pull docker.io/busybox

Tag the new image with the form <registry_ip>:<port>/<project>/<image>. The project name must appear in this pull specification for OpenShift Container Platform to correctly place and later access the image in the registry.

$ docker tag docker.io/busybox 172.30.124.220:5000/openshift/busybox

Note

Your regular user must have the system:image-builder role for the specified project, which allows the user to write or push an image. Otherwise, the docker push in the next step will fail. To test, you can create a new project to push the busybox image.

Push the newly-tagged image to your registry:

$ docker push 172.30.124.220:5000/openshift/busybox
...
cf2616975b4a: Image successfully pushed
Digest: sha256:3662dd821983bc4326bee12caec61367e7fb6f6a3ee547cbaff98f77403cab55

Securing and Exposing the Registry

Securing the Registry

Optionally, you can secure the registry so that it serves traffic via TLS:

Deploy the registry.

Fetch the service IP and port of the registry:

$ oc get svc/docker-registry
NAME              LABELS                                    SELECTOR                  IP(S)            PORT(S)
docker-registry   docker-registry=default                   docker-registry=default   172.30.124.220   5000/TCP

You can use an existing server certificate, or create a key and server certificate valid for specified IPs and host names, signed by a specified CA. To create a server certificate for the registry service IP and the docker-registry.default.svc.cluster.local host name:

$ oadm ca create-server-cert \
    --signer-cert=/etc/origin/master/ca.crt \
    --signer-key=/etc/origin/master/ca.key \
    --signer-serial=/etc/origin/master/ca.serial.txt \
    --hostnames='docker-registry.default.svc.cluster.local,172.30.124.220' \
    --cert=/etc/secrets/registry.crt \
    --key=/etc/secrets/registry.key

If the router will be exposed externally, add the public route host name in the --hostnames flag:

--hostnames='mydocker-registry.example.com,docker-registry.default.svc.cluster.local,172.30.124.220

Note

The oadm ca create-server-cert command generates a certificate that is valid for two years. This can be altered with the --expire-days option, but for security reasons, it is recommended to not make it greater than this value.

Create the secret for the registry certificates:

$ oc secrets new registry-secret \
    /etc/secrets/registry.crt \
    /etc/secrets/registry.key

Add the secret to the registry pod’s service accounts (including the default service account):

$ oc secrets link registry registry-secret
$ oc secrets link default  registry-secret

Note

Limiting secrets to only the service accounts that reference them is disabled by default. This means that if serviceAccountConfig.limitSecretReferences is set to false (the default setting) in the master configuration file, linking secrets to a service is not required.

Add the secret volume to the registry deployment configuration:

$ oc volume dc/docker-registry --add --type=secret \
    --secret-name=registry-secret -m /etc/secrets

Enable TLS by adding the following environment variables to the registry deployment configuration:

$ oc set env dc/docker-registry \
    REGISTRY_HTTP_TLS_CERTIFICATE=/etc/secrets/registry.crt \
    REGISTRY_HTTP_TLS_KEY=/etc/secrets/registry.key

See more details on overriding registry options.

Update the scheme used for the registry’s liveness probe from HTTP to HTTPS:

$ oc patch dc/docker-registry -p '{"spec": {"template": {"spec": {"containers":[{
    "name":"registry",
    "livenessProbe":  {"httpGet": {"scheme":"HTTPS"}}
  }]}}}}'

If your registry was initially deployed on OpenShift Container Platform 3.2 or later, update the scheme used for the registry’s readiness probe from HTTP to HTTPS:

$ oc patch dc/docker-registry -p '{"spec": {"template": {"spec": {"containers":[{
    "name":"registry",
    "readinessProbe":  {"httpGet": {"scheme":"HTTPS"}}
  }]}}}}'

Validate the registry is running in TLS mode. Wait until the latest docker-registry deployment completes and verify the Docker logs for the registry container. You should find an entry for listening on :5000, tls.

$ oc logs dc/docker-registry | grep tls
time="2015-05-27T05:05:53Z" level=info msg="listening on :5000, tls" instance.id=deeba528-c478-41f5-b751-dc48e4935fc2

Copy the CA certificate to the Docker certificates directory. This must be done on all nodes in the cluster:

$ dcertsdir=/etc/docker/certs.d
$ destdir_addr=$dcertsdir/172.30.124.220:5000
$ destdir_name=$dcertsdir/docker-registry.default.svc.cluster.local:5000

$ sudo mkdir -p $destdir_addr $destdir_name
$ sudo cp ca.crt $destdir_addr
$ sudo cp ca.crt $destdir_name

The ca.crt file is a copy of /etc/origin/master/ca.crt on the master.

Remove the --insecure-registry option only for this particular registry in the /etc/sysconfig/docker file. Then, reload the daemon and restart the docker service to reflect this configuration change:

$ sudo systemctl daemon-reload
$ sudo systemctl restart docker

Validate the docker client connection. Running docker push to the registry or docker pull from the registry should succeed. Make sure you have logged into the registry.

$ docker tag|push <registry/image> <internal_registry/project/image>

For example:

$ docker pull busybox
$ docker tag docker.io/busybox 172.30.124.220:5000/openshift/busybox
$ docker push 172.30.124.220:5000/openshift/busybox
...
cf2616975b4a: Image successfully pushed
Digest: sha256:3662dd821983bc4326bee12caec61367e7fb6f6a3ee547cbaff98f77403cab55

Exposing the Registry

To expose your internal registry externally, it is recommended that you run a secure registry. To expose the registry you must first have deployed a router.

Deploy the registry.

Secure the registry.

Deploy a router.

Create a passthrough route via the oc create route passthrough command, specifying the registry as the route’s service. By default, the name of the created route is the same as the service name.

For example:

$ oc get svc
NAME              CLUSTER_IP       EXTERNAL_IP   PORT(S)                 SELECTOR                  AGE
docker-registry   172.30.69.167    <none>        5000/TCP                docker-registry=default   4h
kubernetes        172.30.0.1       <none>        443/TCP,53/UDP,53/TCP   <none>                    4h
router            172.30.172.132   <none>        80/TCP                  router=router             4h

$ oc create route passthrough    \
    --service=docker-registry    \
    --hostname=<host>
route "docker-registry" created

Specify the registry as the route’s service.

The route name is identical to the service name.

$ oc get route/docker-registry -o yaml
apiVersion: v1
kind: Route
metadata:
  name: docker-registry
spec:
  host: <host>
  to:
    kind: Service
    name: docker-registry
  tls:
    termination: passthrough

The host for your route. You must be able to resolve this name externally via DNS to the router’s IP address.

The service name for your registry.

Specify this route as a passthrough route.

Note

Passthrough is currently the only type of route supported for exposing the secure registry.

Next, you must trust the certificates being used for the registry on your host system. The certificates referenced were created when you secured your registry.

$ sudo mkdir -p /etc/docker/certs.d/<host>
$ sudo cp <ca certificate file> /etc/docker/certs.d/<host>
$ sudo systemctl restart docker

Log in to the registry using the information from securing the registry. However, this time point to the host name used in the route rather than your service IP. You should now be able to tag and push images using the route host.

$ oc get imagestreams -n test
NAME      DOCKER REPO   TAGS      UPDATED

$ docker pull busybox
$ docker tag busybox <host>/test/busybox
$ docker push <host>/test/busybox
The push refers to a repository [<host>/test/busybox] (len: 1)
8c2e06607696: Image already exists
6ce2e90b0bc7: Image successfully pushed
cf2616975b4a: Image successfully pushed
Digest: sha256:6c7e676d76921031532d7d9c0394d0da7c2906f4cb4c049904c4031147d8ca31

$ docker pull <host>/test/busybox
latest: Pulling from <host>/test/busybox
cf2616975b4a: Already exists
6ce2e90b0bc7: Already exists
8c2e06607696: Already exists
Digest: sha256:6c7e676d76921031532d7d9c0394d0da7c2906f4cb4c049904c4031147d8ca31
Status: Image is up to date for <host>/test/busybox:latest

$ oc get imagestreams -n test
NAME      DOCKER REPO                       TAGS      UPDATED
busybox   172.30.11.215:5000/test/busybox   latest    2 seconds ago

Note

Your image streams will have the IP address and port of the registry service, not the route name and port. See oc get imagestreams for details.

Note

In the <host>/test/busybox example above, test refers to the project name.

Exposing a Secure Registry

Instead of logging in to the registry from within the OpenShift Container Platform cluster, you can gain external access to it by first securing the registry and then exposing the registry. This allows you to log in to the registry from outside the cluster using the route address, and to tag and push images using the route host.

When logging in to the secured and exposed registry, make sure you specify the registry in the login command. For example:

docker login -e user@company.com -u f83j5h6 -p Ju1PeM47R0B92Lk3AZp-bWJSck2F7aGCiZ66aFGZrs2 registry.example.com:80

Exposing a Non-Secure Registry

Instead of securing the registry in order to expose the registry, you can simply expose a non-secure registry for non-production OpenShift Container Platform environments. This allows you to have an external route to the registry without using SSL certificates.

Warning

Only non-production environments should expose a non-secure registry to external access.

To expose a non-secure registry:

Expose the registry:

# oc expose service docker-registry --hostname=<hostname> -n default

This creates the following JSON file:

apiVersion: v1
kind: Route
metadata:
  creationTimestamp: null
  labels:
    docker-registry: default
  name: docker-registry
spec:
  host: registry.example.com
  port:
    targetPort: "5000"
  to:
    kind: Service
    name: docker-registry
status: {}

Verify that the route has been created successfully:

# oc get route
NAME              HOST/PORT                    PATH      SERVICE           LABELS                    INSECURE POLICY   TLS TERMINATION
docker-registry   registry.example.com            docker-registry   docker-registry=default

Check the health of the registry:

$ curl -v http://registry.example.com/healthz

Expect an HTTP 200/OK message.

After exposing the registry, update your /etc/sysconfig/docker file by adding the port number to the OPTIONS entry. For example:

OPTIONS='--selinux-enabled --insecure-registry=172.30.0.0/16 --insecure-registry registry.example.com:80'

Important

The above options should be added on the client from which you are trying to log in.

Also, ensure that Docker is running on the client.

When logging in to the non-secured and exposed registry, make sure you specify the registry in the login command. For example:

docker login -e user@company.com -u f83j5h6 -p Ju1PeM47R0B92Lk3AZp-bWJSck2F7aGCiZ66aFGZrs2 registry.example.com:80

Extended Registry Configuration

Maintaining the Registry IP Address

OpenShift Container Platform refers to the integrated registry by its service IP address, so if you decide to delete and recreate the docker-registry service, you can ensure a completely transparent transition by arranging to re-use the old IP address in the new service. If a new IP address cannot be avoided, you can minimize cluster disruption by rebooting only the masters.

Re-using the Address

To re-use the IP address, you must save the IP address of the old docker-registry service prior to deleting it, and arrange to replace the newly assigned IP address with the saved one in the new docker-registry service.

Make a note of the clusterIP for the service:

$ oc get svc/docker-registry -o yaml | grep clusterIP:

Delete the service:

$ oc delete svc/docker-registry dc/docker-registry

Create the registry definition in registry.yaml, replacing <options> with, for example, those used in step 3 of the instructions in the Non-Production Use section:

$ oadm registry <options> -o yaml > registry.yaml

Edit registry.yaml, find the Service there, and change its clusterIP to the address noted in step 1.

Create the registry using the modified registry.yaml:

$ oc create -f registry.yaml

Rebooting the Masters

If you are unable to re-use the IP address, any operation that uses a pull specification that includes the old IP address will fail. To minimize cluster disruption, you must reboot the masters:

# systemctl restart atomic-openshift-master

This ensures that the old registry URL, which includes the old IP address, is cleared from the cache.

Note

We recommend against rebooting the entire cluster because that incurs unnecessary downtime for pods and does not actually clear the cache.

Whitelisting Docker Registries

You can specify a whitelist of docker registries, allowing you to curate a set of images and templates that are available for download by OpenShift Container Platform users. This curated set can be placed in one or more docker registries, and then added to the whitelist. When using a whitelist, only the specified registries are accessible within OpenShift Container Platform, and all other registries are denied access by default.

To configure a whitelist:

Edit the /etc/sysconfig/docker file to block all registries:

BLOCK_REGISTRY='--block-registry=all'

You may need to uncomment the BLOCK_REGISTRY line.

In the same file, add registries to which you want to allow access:

ADD_REGISTRY='--add-registry=<registry1> --add-registry=<registry2>'

Example 3.1. Allowing Access to Registries

ADD_REGISTRY='--add-registry=registry.access.redhat.com'

This example would restrict access to images available on the Red Hat Customer Portal.

Once the whitelist is configured, if a user tries to pull from a docker registry that is not on the whitelist, they will receive an error message stating that this registry is not allowed.

Overriding the Registry Configuration

You can override the integrated registry’s default configuration, found by default at /config.yml in a running registry’s container, with your own custom configuration.

Note

Upstream configuration options in this file may also be overridden using environment variables. The middleware section is an exception as there are just a few options that can be overridden using environment variables. Learn how to override specific configuration options.

To enable management of the registry configuration file directly and deploy an updated configuration, mount the configuration file as a secret volume:

Deploy the registry.

Edit the registry configuration file locally as needed. The initial YAML file deployed on the registry is provided below. Review supported options.

Example 3.2. Registry Configuration File

version: 0.1
log:
  level: debug
http:
  addr: :5000
storage:
  cache:
    blobdescriptor: inmemory
  filesystem:
    rootdirectory: /registry
  delete:
    enabled: true
auth:
  openshift:
    realm: openshift
middleware:
  registry:
    - name: openshift
  repository:
    - name: openshift
      options:
        acceptschema2: false
        pullthrough: true
        enforcequota: false
        projectcachettl: 1m
        blobrepositorycachettl: 10m
  storage:
    - name: openshift

Create a new secret called registry-config from your custom registry configuration file you edited locally:

$ oc secrets new registry-config config.yml=</path/to/custom/registry/config.yml>

Add the registry-config secret as a volume to the registry’s deployment configuration to mount the custom configuration file at /etc/docker/registry/:

$ oc volume dc/docker-registry --add --type=secret \
    --secret-name=registry-config -m /etc/docker/registry/

Update the registry to reference the configuration path from the previous step by adding the following environment variable to the registry’s deployment configuration:

$ oc set env dc/docker-registry \
    REGISTRY_CONFIGURATION_PATH=/etc/docker/registry/config.yml

This may be performed as an iterative process to achieve the desired configuration. For example, during troubleshooting, the configuration may be temporarily updated to put it in debug mode.

To update an existing configuration:

Warning

This procedure will overwrite the currently deployed registry configuration.

Edit the local registry configuration file, config.yml.

Delete the registry-config secret:

$ oc delete secret registry-config

Recreate the secret to reference the updated configuration file:

$ oc secrets new registry-config config.yml=</path/to/custom/registry/config.yml>

Redeploy the registry to read the updated configuration:

$ oc deploy docker-registry --latest

Tip

Maintain configuration files in a source control repository.

Registry Configuration Reference

There are many configuration options available in the upstream docker distribution library. Not all configuration options are supported or enabled. Use this section as a reference when overriding the registry configuration.

Note

Upstream configuration options in this file may also be overridden using environment variables. However, the middleware section may not be overridden using environment variables. Learn how to override specific configuration options.

Log

Upstream options are supported.

Example:

log:
  level: debug
  formatter: text
  fields:
    service: registry
    environment: staging

Hooks

Mail hooks are not supported.

Storage

The following storage drivers are supported:

Filesystem

S3. Learn more about CloudFront configuration.

OpenStack Swift

Google Cloud Storage (GCS)

General registry storage configuration options are supported.

Example 3.3. General Storage Configuration Options

storage:
  delete:
    enabled: true
  redirect:
    disable: false
  cache:
    blobdescriptor: inmemory
  maintenance:
    uploadpurging:
      enabled: true
      age: 168h
      interval: 24h
      dryrun: false
    readonly:
      enabled: false

This entry is mandatory for image pruning to work properly.

Auth

Auth options should not be altered. The openshift extension is the only supported option.

auth:
  openshift:
    realm: openshift

Middleware

The repository middleware extension allows to configure OpenShift Container Platform middleware responsible for interaction with OpenShift Container Platform and image proxying.

middleware:
  registry:
    - name: openshift
  repository:
    - name: openshift
      options:
        acceptschema2: false
        pullthrough: true
        enforcequota: false
        projectcachettl: 1m
        blobrepositorycachettl: 10m
  storage:
    - name: openshift

These entries are mandatory. Their presence ensures required components get loaded. These values shouldn’t be changed.

Allow to store manifest schema v2 during a push to the registry. See below for more details.

Let the registry act as a proxy for remote blobs. See below for more details.

Prevent blob uploads exceeding size limit defined in targeted project.

An expiration timeout for limits cached in the registry. The lower the value, the less time will it take for the limit changes to propagate to the registry. However, the registry will query limits from the server more frequently and, as a consequence, pushes will be slower.

An expiration timeout for remembered associations between blob and repository. The higher the value, the higher probability of fast lookup and more efficient registry operation. On the other hand, memory usage will raise as well as a risk of serving image layer to user, who is no longer authorized to access it.

CloudFront Middleware

The CloudFront middleware extension can be added to support AWS, CloudFront CDN storage provider. CloudFront middleware speeds up distribution of image content internationally. The blobs are distributed to several edge locations around the world. The client is always directed to the edge with the lowest latency.

Note

The CloudFront middleware extension can be only used with S3 storage. It is utilized only during blob serving. Therefore, only blob downloads can be speeded up, not uploads.

The following is an example of minimal configuration of S3 storage driver with a CloudFront middleware:

version: 0.1
log:
  level: debug
http:
  addr: :5000
storage:
  cache:
    blobdescriptor: inmemory
  delete:
    enabled: true
  s3:
    accesskey: BJKMSZBRESWJQXRWMAEQ
    secretkey: 5ah5I91SNXbeoUXXDasFtadRqOdy62JzlnOW1goS
    region: us-east-1
    bucket: docker.myregistry.com
auth:
  openshift:
    realm: openshift
middleware:
  registry:
    - name: openshift
  repository:
    - name: openshift
   storage:
    - name: cloudfront
      options:
        baseurl: https://jrpbyn0k5k88bi.cloudfront.net/
        privatekey: /etc/docker/cloudfront-ABCEDFGHIJKLMNOPQRST.pem
        keypairid: ABCEDFGHIJKLMNOPQRST
    - name: openshift

The S3 storage must be configured the same way regardless of CloudFront middleware.

The CloudFront storage middleware needs to be listed before OpenShift middleware.

The CloudFront base URL. In the AWS management console, this is listed as Domain Name of CloudFront distribution.

The location of your AWS private key on the filesystem. This must be not confused with Amazon EC2 key pair. Please refer to AWS documentation on creating CloudFront key pairs for your trusted signers. The file needs to be mounted as a secret secret into the registry pod.

The ID of your Cloudfront key pair.

Overriding Middleware Configuration Options

The middleware section cannot be overridden using environment variables. There are a few exceptions, however. For example:

middleware:
  repository:
    - name: openshift
      options:
        acceptschema2: false
        enforcequota: false
        projectcachettl: 1m
        blobrepositorycachettl: 10m

A configuration option that can be overridden by the boolean environment variable REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_ACCEPTSCHEMA2, which allows for the ability to accept manifest schema v2 on manifest put requests.

A configuration option that can be overridden by the boolean environment variable REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_ENFORCEQUOTA, which allows the ability to turn quota enforcement on or off. By default, quota enforcement is off. It overrides OpenShift Container Platform middleware configuration option. Recognized values are true and false.

A configuration option that can be overridden by the environment variable REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_PROJECTCACHETTL, specifying an eviction timeout for project quota objects. It takes a valid time duration string (for example, 2m). If empty, you get the default timeout. If zero (0m), caching is disabled.

A configuration option that can be overriden by the environment variable REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_BLOBREPOSITORYCACHETTL, specifying an eviction timeout for associations between blob and containing repository. The format of the value is the same as in projectcachettl case.

Image Pullthrough

If enabled, the registry will attempt to fetch requested blob from a remote registry unless the blob exists locally. The remote candidates are calculated from DockerImage entries stored in status of the image stream, a client pulls from. All the unique remote registry references in such entries will be tried in turn until the blob is found. The blob, served this way, will not be stored in the registry.

This feature is on by default. However, it can be disabled using a configuration option.

Manifest Schema v2 Support

Each image has a manifest describing its blobs, instructions for running it and additional metadata. The manifest is versioned which have different structure and fields as it evolves over time. The same image can be represented by multiple manifest versions. Each version will have different digest though.

The registry currently supports manifest v2 schema 1 (schema1) and manifest v2 schema 2 (schema2). The former is being obsoleted but will be supported for an extended amount of time.

You should be wary of compatibility issues with various Docker clients:

Docker clients of version 1.9 or older support only schema1. Any manifest this client pulls or pushes will be of this legacy schema.

Docker clients of version 1.10 support both schema1 and schema2. And by default, it will push the latter to the registry if it supports newer schema.

The registry, storing an image with schema1 will always return it unchanged to the client. Schema2 will be transferred unchanged only to newer Docker client. For the older one, it will be converted on-the-fly to schema1.

This has significant consequences. For example an image pushed to the registry by a newer Docker client cannot be pulled by the older Docker by its digest. That’s because the stored image’s manifest is of schema2 and its digest can be used to pull only this version of manifest.

For this reason, the registry is configured by default not to store schema2. This ensures that any docker client will be able to pull from the registry any image pushed there regardless of client’s version.

Once you’re confident that all the registry clients support schema2, you’ll be safe to enable its support in the registry. See the middleware configuration reference above for particular option.

Reporting

Reporting is unsupported.

HTTP

Upstream options are supported. Learn how to alter these settings via environment variables. Only the tls section should be altered. For example:

http:
  addr: :5000
  tls:
    certificate: /etc/secrets/registry.crt
    key: /etc/secrets/registry.key

Notifications

Upstream options are supported. The REST API Reference provides more comprehensive integration options.

Example:

notifications:
  endpoints:
    - name: registry
      disabled: false
      url: https://url:port/path
      headers:
        Accept:
          - text/plain
      timeout: 500
      threshold: 5
      backoff: 1000

Redis

Redis is not supported.

Health

Upstream options are supported. The registry deployment configuration provides an integrated health check at /healthz.

Proxy

Proxy configuration should not be enabled. This functionality is provided by the OpenShift Container Platform repository middleware extension, pullthrough: true.

Known Issues

Overview

The following are the known issues when deploying or using the integrated registry.

Image Push Errors with Scaled Registry Using Shared NFS Volume

When using a scaled registry with a shared NFS volume, you may see one of the following errors during the push of an image:

digest invalid: provided digest did not match uploaded content

blob upload unknown

blob upload invalid

These errors are returned by an internal registry service when Docker attempts to push the image. Its cause originates in the synchronization of file attributes across nodes. Factors such as NFS client side caching, network latency, and layer size can all contribute to potential errors that might occur when pushing an image using the default round-robin load balancing configuration.

You can perform the following steps to minimize the probability of such a failure:

Ensure that the sessionAffinity of your docker-registry service is set to ClientIP:

$ oc get svc/docker-registry --template='{{.spec.sessionAffinity}}'

This should return ClientIP, which is the default in recent OpenShift Container Platform versions. If not, change it:

$ oc get -o yaml svc/docker-registry | \
      sed 's/\(sessionAffinity:\s*\).*/\1ClientIP/' | \
      oc replace -f -

Ensure that the NFS export line of your registry volume on your NFS server has the no_wdelay options listed. See Export Settings in the Persistent Storage Using NFS topic for details.

Pull of Internally Managed Image Fails with "not found" Error

This error occurs when the pulled image is pushed to an image stream different from the one it is being pulled from. This is caused by re-tagging a built image into an arbitrary image stream:

$ oc tag srcimagestream:latest anyproject/pullimagestream:latest

And subsequently pulling from it, using an image reference such as:

internal.registry.url:5000/anyproject/pullimagestream:latest

During a manual Docker pull, this will produce a similar error:

Error: image anyproject/pullimagestream:latest not found

To prevent this, avoid the tagging of internally managed images completely, or re-push the built image to the desired namespace manually.

Image Push Fails with "500 Internal Server Error" on S3 Storage

There are problems reported happening when the registry runs on S3 storage back-end. Pushing to a Docker registry occasionally fails with the following error:

Received unexpected HTTP status: 500 Internal Server Error

To debug this, you need to view the registry logs. In there, look for similar error messages occurring at the time of the failed push:

time="2016-03-30T15:01:21.22287816-04:00" level=error msg="unknown error completing upload: driver.Error{DriverName:\"s3\", Enclosed:(*url.Error)(0xc20901cea0)}" http.request.method=PUT
...
time="2016-03-30T15:01:21.493067808-04:00" level=error msg="response completed with error" err.code=UNKNOWN err.detail="s3: Put https://s3.amazonaws.com/oso-tsi-docker/registry/docker/registry/v2/blobs/sha256/ab/abe5af443833d60cf672e2ac57589410dddec060ed725d3e676f1865af63d2e2/data: EOF" err.message="unknown error" http.request.method=PUT
...
time="2016-04-02T07:01:46.056520049-04:00" level=error msg="error putting into main store: s3: The request signature we calculated does not match the signature you provided. Check your key and signing method." http.request.method=PUT
atest

If you see such errors, contact your Amazon S3 support. There may be a problem in your region or with your particular bucket.

Image Pruning Fails

If you encounter the following error when pruning images:

BLOB sha256:49638d540b2b62f3b01c388e9d8134c55493b1fa659ed84e97cb59b87a6b8e6c error deleting blob

And your registry log contains the following information:

error deleting blob \"sha256:49638d540b2b62f3b01c388e9d8134c55493b1fa659ed84e97cb59b87a6b8e6c\": operation unsupported

It means that your custom configuration file lacks mandatory entries in the storage section, namely storage:delete:enabled set to true. Add them, re-deploy the registry, and repeat your image pruning operation.

Chapter 4. Setting up a Router

Router Overview

About Routers

The OpenShift Container Platform router is the ingress point for all external traffic destined for services in your OpenShift Container Platform installation. OpenShift Container Platform provides and supports the following two router plug-ins:

The HAProxy template router is the default plug-in. It uses the openshift3/ose-haproxy-router image to run an HAProxy instance alongside the template router plug-in inside a container on OpenShift Container Platform. It currently supports HTTP(S) traffic and TLS-enabled traffic via SNI. The router’s container listens on the host network interface, unlike most containers that listen only on private IPs. The router proxies external requests for route names to the IPs of actual pods identified by the service associated with the route.

The F5 router integrates with an existing F5 BIG-IP® system in your environment to synchronize routes. F5 BIG-IP® version 11.4 or newer is required in order to have the F5 iControl REST API.

Note

The F5 router plug-in is available starting in OpenShift Container Platform 3.0.2.

Router Service Account

Before deploying an OpenShift Container Platform cluster, you must have a service account for the router. Starting in OpenShift Container Platform 3.1, a router service account is automatically created during a quick or advanced installation (previously, this required manual creation). This service account has permissions to a security context constraint (SCC) that allows it to specify host ports.

Use of labels (e.g., to define router shards) requires cluster-reader permission.

$ oadm policy add-cluster-role-to-user \
    cluster-reader \
    system:serviceaccount:default:router

Using the Default HAProxy Router

Overview

The oadm router command is provided with the administrator CLI to simplify the tasks of setting up routers in a new installation. If you followed the quick installation, then a default router was automatically created for you. The oadm router command creates the service and deployment configuration objects. Just about every form of communication between OpenShift Container Platform components is secured by TLS and uses various certificates and authentication methods. Use the --service-account option to specify the service account the router will use to contact the master.

Important

Routers directly attach to port 80 and 443 on all interfaces on a host. Restrict routers to hosts where port 80/443 is available and not being consumed by another service, and set this using node selectors and the scheduler configuration. As an example, you can achieve this by dedicating infrastructure nodes to run services such as routers.

Important

It is recommended to use separate distinct openshift-router service account with your router. This can be provided using the --service-account flag to the oadm router command.

$ oadm router --dry-run --service-account=router

--service-account is the name of a service account for the openshift-router.

Important

Router pods created using oadm router have default resource requests that a node must satisfy for the router pod to be deployed. In an effort to increase the reliability of infrastructure components, the default resource requests are used to increase the QoS tier of the router pods above pods without resource requests. The default values represent the observed minimum resources required for a basic router to be deployed and can be edited in the routers deployment configuration and you may want to increase them based on the load of the router.

Creating a Router

The quick installation process automatically creates a default router. If the router does not exist, run the following to create a router:

$ oadm router <router_name> --replicas=<number> --service-account=router

You can also use router shards to ensure that the router is filtered to specific namespaces or routes, or set any environment variables after router creation.

Other Basic Router Commands

Checking the Default Router

The default router service account, named router, is automatically created during quick and advanced installations. To verify that this account already exists:

$ oadm router --dry-run --service-account=router

Viewing the Default Router

To see what the default router would look like if created:

$ oadm router -o yaml --service-account=router

Deploying the Router to a Labeled Node

To deploy the router to any node(s) that match a specified node label:

$ oadm router <router_name> --replicas=<number> --selector=<label> \
    --service-account=router

For example, if you want to create a router named router and have it placed on a node labeled with region=infra:

$ oadm router router --replicas=1 --selector='region=infra' \
  --service-account=router

During advanced installation, the openshift_hosted_router_selector and openshift_registry_selector Ansible settings are set to region=infra by default. The default router and registry will only be automatically deployed if a node exists that matches the region=infra label.

Multiple instances are created on different hosts according to the scheduler policy.

Using a Different Router Image

To use a different router image and view the router configuration that would be used:

$ oadm router <router_name> -o <format> --images=<image> \
    --service-account=router

For example:

$ oadm router region-west -o yaml --images=myrepo/somerouter:mytag \
    --service-account=router

Filtering Routes to Specific Routers

Using the ROUTE_LABELS environment variable, you can filter routes so that they are used only by specific routers.

For example, if you have multiple routers, and 100 routes, you can attach labels to the routes so that a portion of them are handled by one router, whereas the rest are handled by another.

After creating a router, use the ROUTE_LABELS environment variable to tag the router:

$ oc env dc/<router=name>  ROUTE_LABELS="key=value"

Add the label to the desired routes:

oc label route <route=name> key=value

To verify that the label has been attached to the route, check the route configuration:

$ oc describe dc/<route_name>

Highly-Available Routers

You can set up a highly-available router on your OpenShift Container Platform cluster using IP failover.

Customizing the Router Service Ports

You can customize the service ports that a template router binds to by setting the environment variables ROUTER_SERVICE_HTTP_PORT and ROUTER_SERVICE_HTTPS_PORT. This can be done by creating a template router, then editing its deployment configuration.

The following example creates a router deployment with 0 replicas and customizes the router service HTTP and HTTPS ports, then scales it appropriately (to 1 replica).

$ oadm router --replicas=0 --ports='10080:10080,10443:10443'
$ oc set env dc/router ROUTER_SERVICE_HTTP_PORT=10080  \
                   ROUTER_SERVICE_HTTPS_PORT=10443
$ oc scale dc/router --replicas=1

Ensures exposed ports are appropriately set for routers that use the container networking mode --host-network=false.

Important

If you do customize the template router service ports, you will also need to ensure that the nodes where the router pods run have those custom ports opened in the firewall (either via Ansible or iptables, or any other custom method that you use via firewall-cmd).

The following is an example using iptables to open the custom router service ports.

$ iptables -A INPUT -p tcp --dport 10080 -j ACCEPT
$ iptables -A INPUT -p tcp --dport 10443 -j ACCEPT

Working With Multiple Routers

An administrator can create multiple routers with the same definition to serve the same set of routes. By having different groups of routers with different namespace or route selectors, they can vary the routes that the router serves.

Multiple routers can be grouped to distribute routing load in the cluster and separate tenants to different routers or shards. Each router or shard in the group handles routes based on the selectors in the router. An administrator can create shards over the whole cluster using ROUTE_LABELS. A user can create shards over a namespace (project) by using NAMESPACE_LABELS.

Adding a Node Selector to a Deployment Configuration

Making specific routers deploy on specific nodes requires two steps:

Add a label to the desired node:

$ oc label node 10.254.254.28 "router=first"

Add a node selector to the router deployment configuration:

$ oc edit dc <deploymentConfigName>

Add the template.spec.nodeSelector field with a key and value corresponding to the label:

...
  template:
    metadata:
      creationTimestamp: null
      labels:
        router: router1
    spec:
      nodeSelector:
        router: "first"
...

The key and value are router and first, respectively, corresponding to the router=first label.

Using Router Shards

The access controls are based on the service account that the router is run with.

Using NAMESPACE_LABELS and/or ROUTE_LABELS, a router can filter out the namespaces and/or routes that it should service. This enables you to partition routes amongst multiple router deployments effectively distributing the set of routes.

Example: A router deployment finops-router is run with route selector NAMESPACE_LABELS="name in (finance, ops)" and a router deployment dev-router is run with route selector NAMESPACE_LABELS="name=dev".

If all routes are in the 3 namespaces finance, ops or dev, then this could effectively distribute our routes across two router deployments.

In the above scenario, sharding becomes a special case of partitioning with no overlapping sets. Routes are divided amongst multiple router shards.

The criteria for route selection governs how the routes are distributed. It is possible to have routes that overlap accross multiple router deployments.

Example: In addition to the finops-router and dev-router in the example above, we also have an devops-router which is run with a route selector NAMESPACE_LABELS="name in (dev, ops)".

The routes in namespaces dev or ops now are serviced by two different router deployments. This becomes a case where we have partitioned the routes with an overlapping set.

In addition, this enables us to create more complex routing rules ala divert high priority traffic to the dedicated finops-router but send the lower priority ones to the devops-router.

NAMESPACE_LABELS allows filtering the projects to service and selecting all the routes from those projects. But we may want to partition routes based on other criteria in the routes themselves. The ROUTE_LABELS selector allows you to slice-and-dice the routes themselves.

Example: A router deployment prod-router is run with route selector ROUTE_LABELS="mydeployment=prod" and a router deployment devtest-router is run with route selector ROUTE_LABELS="mydeployment in (dev, test)"

Example assumes you have all the routes you wish to serviced tagged with a label "mydeployment=<tag>".

Creating Router Shards

Router sharding lets you select how routes are distributed among a set of routers.

Router sharding is based on labels; you set labels on the routes in the pool, and express the desired subset of those routes for the router to serve with a selection expression via the oc set env command.

First, ensure that service account associated with the router has the cluster reader permission.

The rest of this section describes an extended example. Suppose there are 26 routes, named a — z, in the pool, with various labels:

Possible labels on routes in the pool

sla=high       geo=east     hw=modest     dept=finance
sla=medium     geo=west     hw=strong     dept=dev
sla=low                                   dept=ops

These labels express the concepts: service level agreement, geographical location, hardware requirements, and department. The routes in the pool can have at most one label from each column. Some routes may have other labels, entirely, or none at all.

Name(s)
SLA
Geo
HW
Dept
Other Labels

a

high

east

modest

finance

type=static

b

west

strong

type=dynamic

c, d, e

low

modest

type=static

g — k

medium

strong

dev

l — s

high

modest

ops

t — z

west

type=dynamic

Here is a convenience script mkshard that ilustrates how oadm router, oc set env, and oc scale work together to make a router shard.

#!/bin/bash
# Usage: mkshard ID SELECTION-EXPRESSION
id=$1
sel="$2"
router=router-shard-$id
oadm router $router --replicas=0
dc=dc/router-shard-$id
oc set env   $dc ROUTE_LABELS="$sel"
oc scale $dc --replicas=3

The created router has name router-shard-<id>.

Specify no scaling for now.

The deployment configuration for the router.

Set the selection expression using oc set env. The selection expression is the value of the ROUTE_LABELS environment variable.

Scale it up.

Running mkshard several times creates several routers:

Router
Selection Expression
Routes

router-shard-1

sla=high

a, l — s

router-shard-2

geo=west

b, t — z

router-shard-3

dept=dev

g — k

Modifying Router Shards

Because a router shard is a construct based on labels, you can modify either the labels (via oc label) or the selection expression.

This section extends the example started in the Creating Router Shards section, demonstrating how to change the selection expression.

Here is a convenience script modshard that modifies an existing router to use a new selection expression:

#!/bin/bash
# Usage: modshard ID SELECTION-EXPRESSION...
id=$1
shift
router=router-shard-$id
dc=dc/$router
oc scale $dc --replicas=0
oc set env   $dc "$@"
oc scale $dc --replicas=3

The modified router has name router-shard-<id>.

The deployment configuration where the modifications occur.

Scale it down.

Set the new selection expression using oc set env. Unlike mkshard from the Creating Router Shards section, the selection expression specified as the non-ID arguments to modshard must include the environment variable name as well as its value.

Scale it back up.

Note

In modshard, the oc scale commands are not necessary if the deployment strategy for router-dhsard-<id> is Rolling.

For example, to expand the department for router-shard-3 to include ops as well as dev:

$ modshard 3 ROUTE_LABELS='dept in (dev, ops)'

The result is that router-shard-3 now selects routes g — s (the combined sets of g — k and l — s).

This example takes into account that there are only three departments in this example scenario, and specifies a department to leave out of the shard, thus achieving the same result as the preceding example:

$ modshard 3 ROUTE_LABELS='dept != finanace'

This example specifies shows three comma-separated qualities, and results in only route b being selected:

$ modshard 3 ROUTE_LABELS='hw=strong,type=dynamic,geo=west'

Similarly to ROUTE_LABELS, which involve a route’s labels, you can select routes based on the labels of the route’s namespace labels, with the NAMESPACE_LABELS environment variable. This example modifies router-shard-3 to serve routes whose namespace has the label frequency=weekly:

$ modshard 3 NAMESPACE_LABELS='frequency=weekly'

The last example combines ROUTE_LABELS and NAMESPACE_LABELS to select routes with label sla=low and whose namespace has the label frequency=weekly:

$ modshard 3 \
    NAMESPACE_LABELS='frequency=weekly' \
    ROUTE_LABELS='sla=low'

Using Namespace Router Shards

The routes for a project can be handled by a selected router by using NAMESPACE_LABELS. The router is given a selector for a NAMESPACE_LABELS label and the project that wants to use the router applies the NAMESPACE_LABELS label to its namespace.

First, ensure that service account associated with the router has the cluster reader permission. This permits the router to read the labels that are applied to the namespaces.

Now create and label the router:

$ oadm router ...  --service-account=router
$ oc set env dc/router NAMESPACE_LABELS="router=r1"

Because the router has a selector for a namespace, the router will handle routes for that namespace. So, for example:

$ oc label namespace default "router=r1"

Now create routes in the default namespace, and the route is available in the default router:

$ oc create -f route1.yaml

Now create a new project (namespace) and create a route, route2.

$ oc new-project p1
$ oc create -f route2.yaml

And notice the route is not available in your router. Now label namespace p1 with "router=r1"

$ oc label namespace p1 "router=r1"

Which makes the route available to the router.

Note that removing the label from the namespace won’t have immediate effect (as we don’t see the updates in the router), so if you redeploy/start a new router pod, you should see the unlabelled effects.

$ oc scale dc/router --replicas=0 && oc scale dc/router --replicas=1

Customizing the Default Routing Subdomain

You can customize the suffix used as the default routing subdomain for your environment by modifying the master configuration file (the /etc/origin/master/master-config.yaml file by default). Routes that do not specify a host name would have one generated using this default routing subdomain.

The following example shows how you can set the configured suffix to v3.openshift.test:

routingConfig:
  subdomain: v3.openshift.test

Note

This change requires a restart of the master if it is running.

With the OpenShift Container Platform master(s) running the above configuration, the generated host name for the example of a route named no-route-hostname without a host name added to a namespace mynamespace would be:

no-route-hostname-mynamespace.v3.openshift.test

Forcing Route Host Names to a Custom Routing Subdomain

If an administrator wants to restrict all routes to a specific routing subdomain, they can pass the --force-subdomain option to the oadm router command. This forces the router to override any host names specified in a route and generate one based on the template provided to the --force-subdomain option.

The following example runs a router, which overrides the route host names using a custom subdomain template ${name}-${namespace}.apps.example.com.

$ oadm router --force-subdomain='${name}-${namespace}.apps.example.com'

Using Wildcard Certificates

A TLS-enabled route that does not include a certificate uses the router’s default certificate instead. In most cases, this certificate should be provided by a trusted certificate authority, but for convenience you can use the OpenShift Container Platform CA to create the certificate. For example:

$ CA=/etc/origin/master
$ oadm ca create-server-cert --signer-cert=$CA/ca.crt \
      --signer-key=$CA/ca.key --signer-serial=$CA/ca.serial.txt \
      --hostnames='*.cloudapps.example.com' \
      --cert=cloudapps.crt --key=cloudapps.key

The router expects the certificate and key to be in PEM format in a single file:

$ cat cloudapps.crt cloudapps.key $CA/ca.crt > cloudapps.router.pem

From there you can use the --default-cert flag:

$ oadm router --default-cert=cloudapps.router.pem --service-account=router

Note

Browsers only consider wildcards valid for subdomains one level deep. So in this example, the certificate would be valid for a.cloudapps.example.com but not for a.b.cloudapps.example.com.

Using Secured Routes

Currently, password protected key files are not supported. HAProxy prompts for a password upon starting and does not have a way to automate this process. To remove a passphrase from a keyfile, you can run:

# openssl rsa -in <passwordProtectedKey.key> -out <new.key>

Here is an example of how to use a secure edge terminated route with TLS termination occurring on the router before traffic is proxied to the destination. The secure edge terminated route specifies the TLS certificate and key information. The TLS certificate is served by the router front end.

First, start up a router instance:

# oadm router --replicas=1 --service-account=router

Next, create a private key, csr and certificate for our edge secured route. The instructions on how to do that would be specific to your certificate authority and provider. For a simple self-signed certificate for a domain named www.example.test, see the example shown below:

# sudo openssl genrsa -out example-test.key 2048
#
# sudo openssl req -new -key example-test.key -out example-test.csr  \
  -subj "/C=US/ST=CA/L=Mountain View/O=OS3/OU=Eng/CN=www.example.test"
#
# sudo openssl x509 -req -days 366 -in example-test.csr  \
      -signkey example-test.key -out example-test.crt

Generate a route using the above certificate and key.

$ oc create route edge --service=my-service \
    --hostname=www.example.test \
    --key=example-test.key --cert=example-test.crt
route "my-service" created

Look at its definition.

$ oc get route/my-service -o yaml
apiVersion: v1
kind: Route
metadata:
  name:  my-service
spec:
  host: www.example.test
  to:
    kind: Service
    name: my-service
  tls:
    termination: edge
    key: |
      -----BEGIN PRIVATE KEY-----
      [...]
      -----END PRIVATE KEY-----
    certificate: |
      -----BEGIN CERTIFICATE-----
      [...]
      -----END CERTIFICATE-----

Make sure your DNS entry for www.example.test points to your router instance(s) and the route to your domain should be available. The example below uses curl along with a local resolver to simulate the DNS lookup:

# routerip="4.1.1.1"  #  replace with IP address of one of your router instances.
# curl -k --resolve www.example.test:443:$routerip https://www.example.test/

Using the Container Network Stack

The OpenShift Container Platform router runs inside a container and the default behavior is to use the network stack of the host (i.e., the node where the router container runs). This default behavior benefits performance because network traffic from remote clients does not need to take multiple hops through user space to reach the target service and container.

Additionally, this default behavior enables the router to get the actual source IP address of the remote connection rather than getting the node’s IP address. This is useful for defining ingress rules based on the originating IP, supporting sticky sessions, and monitoring traffic, among other uses.

This host network behavior is controlled by the --host-network router command line option, and the default behaviour is the equivalent of using --host-network=true. If you wish to run the router with the container network stack, use the --host-network=false option when creating the router. For example:

$ oadm router --service-account=router --host-network=false

Internally, this means the router container must publish the 80 and 443 ports in order for the external network to communicate with the router.

Note

Running with the container network stack means that the router sees the source IP address of a connection to be the NATed IP address of the node, rather than the actual remote IP address.

Note

On OpenShift Container Platform clusters using multi-tenant network isolation, routers on a non-default namespace with the --host-network=false option will load all routes in the cluster, but routes across the namespaces will not be reachable due to network isolation. With the --host-network=true option, routes bypass the container network and it can access any pod in the cluster. If isolation is needed in this case, then do not add routes across the namespaces.

Exposing Router Metrics

Using the --metrics-image and --expose-metrics options, you can configure the OpenShift Container Platform router to run a sidecar container that exposes or publishes router metrics for consumption by external metrics collection and aggregation systems (e.g. Prometheus, statsd).

Depending on your router implementation, the image is appropriately set up and the metrics sidecar container is started when the router is deployed. For example, the HAProxy-based router implementation defaults to using the prom/haproxy-exporter image to run as a sidecar container, which can then be used as a metrics datasource by the Prometheus server.

Note

The --metrics-image option overrides the defaults for HAProxy-based router implementations and, in the case of custom implementations, enables the image to use for a custom metrics exporter or publisher.

Grab the HAProxy Prometheus exporter image from the Docker registry:

$ sudo docker pull prom/haproxy-exporter

Create the OpenShift Container Platform router:

$ oadm router --service-account=router --expose-metrics

Or, optionally, use the --metrics-image option to override the HAProxy defaults:

$ oadm router --service-account=router --expose-metrics \
    --metrics-image=prom/haproxy-exporter

Once the haproxy-exporter containers (and your HAProxy router) have started, point Prometheus to the sidecar container on port 9101 on the node where the haproxy-exporter container is running:

$ haproxy_exporter_ip="<enter-ip-address-or-hostname>"
$ cat > haproxy-scraper.yml  <<CFGEOF
---
global:
  scrape_interval: "60s"
  scrape_timeout:  "10s"
  # external_labels:
    # source: openshift-router

scrape_configs:
  - job_name:  "haproxy"
    target_groups:
      - targets:
        - "${haproxy_exporter_ip}:9101"
CFGEOF

$ #  And start prometheus as you would normally using the above config file.
$ echo "  - Example:  prometheus -config.file=haproxy-scraper.yml "
$ echo "              or you can start it as a container on {product-title}!!

$ echo "  - Once the prometheus server is up, view the {product-title} HAProxy "
$ echo "    router metrics at: http://<ip>:9090/consoles/haproxy.html "

Preventing Connection Failures During Restarts

If you connect to the router while the proxy is reloading, there is a small chance that your connection will end up in the wrong network queue and be dropped. The issue is being addressed. In the meantime, it is possible to work around the problem by installing iptables rules to prevent connections during the reload window. However, doing so means that the router needs to run with elevated privilege so that it can manipulate iptables on the host. It also means that connections that happen during the reload are temporarily ignored and must retransmit their connection start, lengthening the time it takes to connect, but preventing connection failure.

To prevent this, configure the router to use iptables by changing the service account, and setting an environment variable on the router.

Use a Privileged SCC

When creating the router, allow it to use the privileged SCC. This gives the router user the ability to create containers with root privileges on the nodes:

$ oadm policy add-scc-to-user privileged -z router

Patch the Router Deployment Configuration to Create a Privileged Container

You can now create privileged containers. Next, configure the router deployment configuration to use the privilege so that the router can set the iptables rules it needs. This patch changes the router deployment configuration so that the container that is created runs as privileged (and therefore gets correct capabilities) and run as root:

$ oc patch dc router -p '{"spec":{"template":{"spec":{"containers":[{"name":"router","securityContext":{"privileged":true}}],"securityContext":{"runAsUser": 0}}}}}'

Configure the Router to Use iptables

Set the option on the router deployment configuration:

$ oc set env dc/router -c router DROP_SYN_DURING_RESTART=true

If you used a non-default name for the router, you must change dc/router accordingly.

Protecting Against DDoS Attacks

Add timeout http-request to the default HAProxy router image to protect the deployment against distributed denial-of-service (DDoS) attacks (for example, slowloris):

# and the haproxy stats socket is available at /var/run/haproxy.stats
global
  stats socket ./haproxy.stats level admin

defaults
  option http-server-close
  mode http
  timeout http-request 5s
  timeout connect 5s
  timeout server 10s
  timeout client 30s

timeout http-request is set up to 5 seconds. HAProxy gives a client 5 seconds *to send its whole HTTP request. Otherwise, HAProxy shuts the connection with *an error.

Also, when the environment variable ROUTER_SLOWLORIS_TIMEOUT is set, it limits the amount of time a client has to send the whole HTTP request. Otherwise, HAProxy will shut down the connection.

Setting the environment variable allows information to be captured as part of the router’s deployment configuration and does not require manual modification of the template, whereas manually adding the HAProxy setting requires you to rebuild the router pod and maintain your router template file.

Using annotations implements basic DDoS protections in the HAProxy template router, including the ability to limit the:

number of concurrent TCP connections

rate at which a client can request TCP connections

rate at which HTTP requests can be made

These are enabled on a per route basis because applications can have extremely different traffic patterns.

Table 4.1. HAProxy Template Router Settings

Setting
Description

haproxy.router.openshift.io/rate-limit-connections

Enables the settings be configured (when set to true, for example).

haproxy.router.openshift.io/rate-limit-connections.concurrent-tcp

The number of concurrent TCP connections that can be made by the same IP address on this route.

haproxy.router.openshift.io/rate-limit-connections.rate-tcp

The number of TCP connections that can be opened by a client IP.

haproxy.router.openshift.io/rate-limit-connections.rate-http

The number of HTTP requests that a client IP can make in a 3-second period.

Deploying a Customized HAProxy Router

Overview

The HAProxy router is based on a golang template that generates the HAProxy configuration file from a list of routes. If you want a customized template router to meet your needs, you can customize the template file, build a new container image, and run a customized router. Alternatively you can use a ConfigMap.

One common case for this might be implementing new features within the application back ends. For example, it might be desirable in a highly-available setup to use stick-tables that synchronizes between peers. The router plug-in provides all the facilities necessary to make this customization.

Obtaining the Router Configuration Template

You can obtain a new haproxy-config.template file from the latest router image by running:

# docker run --rm --interactive=true --tty --entrypoint=cat \
    registry.access.redhat.com/openshift3/ose-haproxy-router:v3.0.2.0 haproxy-config.template

Save this content to a file for use as the basis of your customized template.

Using a ConfigMap to Replace the Router Configuration Template

You can use ConfigMap to customize the router instance without rebuilding the router image. The haproxy-config.template, reload-haproxy, and other scripts can be modified as well as creating and modifying router environment variables.

Copy the haproxy-config.template that you want to modify as described above. Modify it as desired.

Create a ConfigMap:

$ oc create configmap customrouter --from-file=haproxy-config.template

The customrouter ConfigMap now contains a copy of the modified haproxy-config.template file.

Modify the router deployment configuration to mount the ConfigMap as a file and point the TEMPLATE_FILE environment variable to it. This can be done via oc set env and oc volume commands, or alternatively by editing the router deployment configuration.

Using oc commands

$ oc set env dc/router \
    TEMPLATE_FILE=/var/lib/haproxy/conf/custom/haproxy-config.template
$ oc volume dc/router --add --overwrite \
    --name=config-volume \
    --mount-path=/var/lib/haproxy/conf/custom \
    --source='{"configMap": { "name": "customrouter"}}'

Editing the Router Deployment Configuration

Use oc edit dc router to edit the router deployment configuration with a text editor.

...
        - name: STATS_USERNAME
          value: admin
        - name: TEMPLATE_FILE
          value: /var/lib/haproxy/conf/custom/haproxy-config.template
        image: openshift/origin-haproxy-routerp
...
        terminationMessagePath: /dev/termination-log
        volumeMounts:
        - mountPath: /var/lib/haproxy/conf/custom
          name: config-volume
      dnsPolicy: ClusterFirst
...
      terminationGracePeriodSeconds: 30
      volumes:
      - configMap:
          name: customrouter
        name: config-volume
  test: false
...

In the spec.container.env field, add the TEMPLATE_FILE environment variable to point to the mounted haproxy-config.template file.

Add the spec.container.volumeMounts field to create the mount point.

Add a new spec.volumes field to mention the ConfigMap.

Save the changes and exit the editor. This restarts the router.

Using Stick Tables

The following example customization can be used in a highly-available routing setup to use stick-tables that synchronize between peers.

Adding a Peer Section

In order to synchronize stick-tables amongst peers you must a define a peers section in your HAProxy configuration. This section determines how HAProxy will identify and connect to peers. The plug-in provides data to the template under the .PeerEndpoints variable to allow you to easily identify members of the router service. You may add a peer section to the haproxy-config.template file inside the router image by adding:

{{ if (len .PeerEndpoints) gt 0 }}
peers openshift_peers
  {{ range $endpointID, $endpoint := .PeerEndpoints }}
    peer {{$endpoint.TargetName}} {{$endpoint.IP}}:1937
  {{ end }}
{{ end }}

Changing the Reload Script

When using stick-tables, you have the option of telling HAProxy what it should consider the name of the local host in the peer section. When creating endpoints, the plug-in attempts to set the TargetName to the value of the endpoint’s TargetRef.Name. If TargetRef is not set, it will set the TargetName to the IP address. The TargetRef.Name corresponds with the Kubernetes host name, therefore you can add the -L option to the reload-haproxy script to identify the local host in the peer section.

peer_name=$HOSTNAME

if [ -n "$old_pid" ]; then
  /usr/sbin/haproxy -f $config_file -p $pid_file -L $peer_name -sf $old_pid
else
  /usr/sbin/haproxy -f $config_file -p $pid_file -L $peer_name
fi

Must match an endpoint target name that is used in the peer section.

Modifying Back Ends

Finally, to use the stick-tables within back ends, you can modify the HAProxy configuration to use the stick-tables and peer set. The following is an example of changing the existing back end for TCP connections to use stick-tables:

            {{ if eq $cfg.TLSTermination "passthrough" }}
backend be_tcp_{{$cfgIdx}}
  balance leastconn
  timeout check 5000ms
  stick-table type ip size 1m expire 5m{{ if (len $.PeerEndpoints) gt 0 }} peers openshift_peers {{ end }}
  stick on src
                {{ range $endpointID, $endpoint := $serviceUnit.EndpointTable }}
  server {{$endpointID}} {{$endpoint.IP}}:{{$endpoint.Port}} check inter 5000ms
                {{ end }}
            {{ end }}

After this modification, you can rebuild your router.

Rebuilding Your Router

After you have made any desired modifications to the template, such as the example stick tables customization, you must rebuild your router for your changes to go in effect:

Rebuild the container image to include your customized template.

Push the resulting image to your repository.

Create the router specifying your new image, either:

in the pod’s object definition directly, or

by adding the --images=<repo>/<image>:<tag> flag to the oadm router command when creating a highly-available routing service.

Using the F5 Router Plug-in

Overview

Note

The F5 router plug-in is available starting in OpenShift Container Platform 3.0.2.

The F5 router plug-in is provided as a container image and run as a pod, just like the default HAProxy router. Deploying the F5 router is done similarly as well, using the oadm router command but providing additional flags (or environment variables) to specify the following parameters for the F5 BIG-IP® host:

Flag
Description

--type=f5-router

Specifies that an F5 router should be launched (the default --type is haproxy-router).

--external-host

Specifies the F5 BIG-IP® host’s management interface’s host name or IP address.

--external-host-username

Specifies the F5 BIG-IP® user name (typically admin).

--external-host-password

Specifies the F5 BIG-IP® password.

--external-host-http-vserver

Specifies the name of the F5 virtual server for HTTP connections.

--external-host-https-vserver

Specifies the name of the F5 virtual server for HTTPS connections.

--external-host-private-key

Specifies the path to the SSH private key file for the F5 BIG-IP® host. Required to upload and delete key and certificate files for routes.

--external-host-insecure

A Boolean flag that indicates that the F5 router should skip strict certificate verification with the F5 BIG-IP® host.

--external-host-partition-path

Specifies the F5 BIG-IP® partition path (the default is /Common).

As with the HAProxy router, the oadm router command creates the service and deployment configuration objects, and thus the replication controllers and pod(s) in which the F5 router itself runs. The replication controller restarts the F5 router in case of crashes. Because the F5 router is only watching routes and endpoints and configuring F5 BIG-IP® accordingly, running the F5 router in this way along with an appropriately configured F5 BIG-IP® deployment should satisfy high-availability requirements.

Deploying the F5 Router

The F5 router must be run in privileged mode because route certificates get copied using scp:

$ oadm policy remove-scc-from-user hostnetwork -z router
$ oadm policy add-scc-to-user privileged -z router

To deploy the F5 router:

First, establish a tunnel using a ramp node, which allows for the routing of traffic to pods through the OpenShift Container Platform SDN.

Run the oadm router command with the appropriate flags. For example:

$ oadm router \
    --type=f5-router \
    --external-host=10.0.0.2 \
    --external-host-username=admin \
    --external-host-password=mypassword \
    --external-host-http-vserver=ose-vserver \
    --external-host-https-vserver=https-ose-vserver \
    --external-host-private-key=/path/to/key \
    --service-account=router

F5 Router Partition Paths

Partition paths allow you to store your OpenShift Container Platform routing configuration in a custom F5 BIG-IP® administrative partition, instead of the default /Common partition. You can use custom administrative partitions to secure F5 BIG-IP® environments. This means that an OpenShift Container Platform-specific configuration stored in F5 BIG-IP® system objects reside within a logical container, allowing administrators to define access control policies on that specific administrative partition.

See the F5 BIG-IP® documentation for more information about administrative partitions.

Use the --external-host-partition-path flag when deploying the F5 router to specify a partition path:

$ oadm router --external-host-partition-path=/OpenShift/zone1 ...

Chapter 5. Upgrading a Cluster

Overview

When new versions of OpenShift Container Platform are released, you can upgrade your existing cluster to apply the latest enhancements and bug fixes. This includes upgrading from previous minor versions, such as release 3.2 to 3.3, and applying asynchronous errata updates within a minor version (3.3.z releases). See the OpenShift Container Platform 3.3 Release Notes to review the latest changes.

Note

Due to the core architectural changes between the major versions, OpenShift Enterprise 2 environments cannot be upgraded to OpenShift Container Platform 3 and require a fresh installation.

Unless noted otherwise, node and masters within a major version are forward and backward compatible, so upgrading your cluster should go smoothly. However, you should not run mismatched versions longer than necessary to upgrade the entire cluster.

In-place or Blue-Green Upgrades

There are two methods for performing OpenShift Container Platform cluster upgrades. You can either do in-place upgrades (automated or manual), or upgrade using a blue-green deployment method.

In-place Upgrades

With in-place upgrades, the cluster upgrade is performed on all hosts in a single cluster. If you installed using the quick or advanced installation and the ~/.config/openshift/installer.cfg.yml or inventory file that was used is available, you can perform an automated in-place upgrade. Alternatively, you can upgrade in-place manually.

Blue-green Deployments

With blue-green deployments, you can reduce downtime caused while upgrading an environment by creating a parallel environment on which the new deployment can be installed. If a problem is detected, and after the new deployment is verified, traffic can be switched over with the option to rollback.

Performing Automated In-place Cluster Upgrades

Overview

If you installed using the advanced installation and the inventory file that was used is available, you can use the upgrade playbook to automate the OpenShift cluster upgrade process. If you installed using the quick installation method and a ~/.config/openshift/installer.cfg.yml file is available, you can use the installer to perform the automated upgrade.

The automated upgrade performs the following steps for you:

Applies the latest configuration.

Upgrades and restart master services.

Upgrades and restart node services.

Applies the latest cluster policies.

Updates the default router if one exists.

Updates the default registry if one exists.

Updates default image streams and InstantApp templates.

Important

Ensure that you have met all prerequisites before proceeding with an upgrade. Failure to do so can result in a failed upgrade.

Preparing for an Automated Upgrade

Important

Before upgrading your cluster to OpenShift Container Platform 3.3, the cluster must be already upgraded to the latest asynchronous release of version 3.2. Cluster upgrades cannot span more than one minor version at a time, so if your cluster is at version 3.0 or 3.1, you must first upgrade incrementally (e.g., 3.0 to 3.1, then 3.1 or 3.2).

To prepare for an automated upgrade:

If you are upgrading from version 3.2 to 3.3, manually disable the 3.2 channel and enable the 3.3 channel on each master and node host:

# subscription-manager repos --disable="rhel-7-server-ose-3.2-rpms" \
    --enable="rhel-7-server-ose-3.3-rpms"\
    --enable="rhel-7-server-extras-rpms"
# yum clean all

For any upgrade path, always ensure that you have the latest version of the atomic-openshift-utils package, which should also update the openshift-ansible-* packages:

# yum update atomic-openshift-utils

Install or update to the following latest available *-excluder packages on each RHEL 7 system, which helps ensure your systems stay on the correct versions of atomic-openshift and docker packages when you are not trying to upgrade, according to the OpenShift Container Platform version:

# yum install atomic-openshift-excluder atomic-openshift-docker-excluder

These packages add entries to the exclude directive in the host’s /etc/yum.conf file.

You must be logged in as a cluster administrative user on the master host for the upgrade to succeed:

$ oc login

After satisfying these steps, there are two methods for running the automated upgrade:

Using the installer

Running the upgrade playbook directly

Choose and follow one of these methods.

Using the Installer to Upgrade

If you installed OpenShift Container Platform using the quick installation method, you should have an installation configuration file located at ~/.config/openshift/installer.cfg.yml. The installer requires this file to start an upgrade.

The installer supports upgrading between minor versions of OpenShift Container Platform (one minor version at a time, e.g., 3.2 to 3.3) as well as between asynchronous errata updates within a minor version (e.g., 3.3.z).

If you have an older format installation configuration file in ~/.config/openshift/installer.cfg.yml from an installation of a previous cluster version, the installer will attempt to upgrade the file to the new supported format. If you do not have an installation configuration file of any format, you can create one manually.

To start an upgrade with the quick installer:

Satisfy the steps in Preparing for an Automated Upgrade to ensure you are using the latest upgrade playbooks.

Run the following command on each host to remove the atomic-openshift packages from the list of yum excludes on the host:

# atomic-openshift-excluder unexclude

Run the installer with the upgrade subcommand:

# atomic-openshift-installer upgrade

Then, follow the on-screen instructions to upgrade to the latest release.

After all master and node upgrades have completed, a recommendation will be printed to reboot all hosts. Before rebooting, run the following command on each master and node host to add the atomic-openshift packages back to the list of yum excludes on the host:

# atomic-openshift-excluder exclude

Then reboot all hosts.

After rebooting, if there are no additional features enabled, you can verify the upgrade. Otherwise, the next step depends on what additional features have you previously enabled.

Feature
Next Step

Aggregated Logging

Upgrade the EFK logging stack.

Cluster Metrics

Upgrade cluster metrics.

Running the Upgrade Playbook Directly

You can run the automated upgrade playbook using Ansible directly, similar to the advanced installation method, if you have an inventory file.

The same v3_3 upgrade playbook can be used to upgrade either of the following to the latest 3.3 release:

Existing OpenShift Container Platform 3.2 clusters

Existing OpenShift Container Platform 3.3 clusters

Upgrading to OpenShift Container Platform 3.3

To run an upgrade from OpenShift Container Platform 3.2 to 3.3:

Satisfy the steps in Preparing for an Automated Upgrade to ensure you are using the latest upgrade playbooks.

Ensure the deployment_type parameter in your inventory file is set to openshift-enterprise.

If you have multiple masters configured and want to enable rolling, full system restarts of the hosts, you can set the openshift_rolling_restart_mode parameter in your inventory file to system. Otherwise, the default value services performs rolling service restarts on HA masters, but does not reboot the systems. See Configuring Cluster Variables for details.

Run the v3_3 upgrade playbook. If your inventory file is located somewhere other than the default /etc/ansible/hosts, add the -i flag to specify the location. If you previously used the atomic-openshift-installer command to run your installation, you can check ~/.config/openshift/hosts (previously located at ~/.config/openshift/.ansible/hosts) for the last inventory file that was used, if needed.

# ansible-playbook [-i </path/to/inventory/file>] \
    /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-cluster/upgrades/v3_3/upgrade.yml

After all master and node upgrades have completed, a recommendation will be printed to reboot all hosts. Before rebooting, run the following command on each master and node host to add the atomic-openshift packages back to the list of yum excludes on the host:

# atomic-openshift-excluder exclude

Then reboot all hosts.

After rebooting, if there are no additional features enabled, you can verify the upgrade. Otherwise, the next step depends on what additional features have you previously enabled.

Feature
Next Step

Aggregated Logging

Upgrade the EFK logging stack.

Cluster Metrics

Upgrade cluster metrics.

Upgrading to OpenShift Container Platform 3.3 Asynchronous Releases

To apply asynchronous errata updates to an existing OpenShift Container Platform 3.3 cluster:

Satisfy the steps in Preparing for an Automated Upgrade to ensure you are using the latest upgrade playbooks.

Run the v3_3 upgrade playbook (the same playbook that is used for upgrading from OpenShift Container Platform 3.2 to 3.3). If your inventory file is located somewhere other than the default /etc/ansible/hosts, add the -i flag to specify the location. If you previously used the atomic-openshift-installer command to run your installation, you can check ~/.config/openshift/hosts (previously located at ~/.config/openshift/.ansible/hosts) for the last inventory file that was used, if needed.

# ansible-playbook [-i </path/to/inventory/file>] \
    /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-cluster/upgrades/v3_3/upgrade.yml

After all master and node upgrades have completed, a recommendation will be printed to reboot all hosts. Before rebooting, run the following command on each master and node host to add the atomic-openshift packages back to the list of yum excludes on the host:

# atomic-openshift-excluder exclude

Then reboot all hosts.

After rebooting, if there are no additional features enabled, you can verify the upgrade. Otherwise, the next step depends on what additional features have you previously enabled.

Feature
Next Step

Aggregated Logging

Upgrade the EFK logging stack.

Cluster Metrics

Upgrade cluster metrics.

Upgrading the EFK Logging Stack

If you have previously deployed the EFK logging stack and want to upgrade to the latest logging component images, the steps must be performed manually as shown in Manual Upgrades.

Upgrading Cluster Metrics

If you have previously deployed cluster metrics, you must manually update to the latest metric components.

Verifying the Upgrade

To verify the upgrade:

First check that all nodes are marked as Ready:

# oc get nodes
NAME                        STATUS                     AGE
master.example.com          Ready,SchedulingDisabled   165d
node1.example.com           Ready                      165d
node2.example.com           Ready                      165d

Then, verify that you are running the expected versions of the docker-registry and router images, if deployed. Replace <tag> with v3.3.1.11 for the latest version.

# oc get -n default dc/docker-registry -o json | grep \"image\"
    "image": "openshift3/ose-docker-registry:<tag>",
# oc get -n default dc/router -o json | grep \"image\"
    "image": "openshift3/ose-haproxy-router:<tag>",

After upgrading, you can use the diagnostics tool on the master to look for common issues:

# oadm diagnostics
...
[Note] Summary of diagnostics execution:
[Note] Completed with no errors or warnings seen.

Performing Manual In-place Cluster Upgrades

Overview

As an alternative to performing an automated upgrade, you can manually upgrade your OpenShift cluster. To manually upgrade without disruption, it is important to upgrade each component as documented in this topic.

Before you begin your upgrade, familiarize yourself now with the entire procedure. Specific releases may require additional steps to be performed at key points before or during the standard upgrade process.

Important

Ensure that you have met all prerequisites before proceeding with an upgrade. Failure to do so can result in a failed upgrade.

Preparing for a Manual Upgrade

Note

Before upgrading your cluster to OpenShift Container Platform 3.3, the cluster must be already upgraded to the latest asynchronous release of version 3.2. Cluster upgrades cannot span more than one minor version at a time, so if your cluster is at version 3.0 or 3.1, you must first upgrade incrementally (e.g., 3.0 to 3.1, then 3.1 or 3.2).

To prepare for a manual upgrade, follow these steps:

If you are upgrading from version 3.2 to 3.3, manually disable the 3.2 channel and enable the 3.3 channel on each host:

# subscription-manager repos --disable="rhel-7-server-ose-3.2-rpms" \
    --enable="rhel-7-server-ose-3.3-rpms" \
    --enable="rhel-7-server-extras-rpms"

On RHEL 7 systems, also clear the yum cache:

# yum clean all

Install or update to the latest available version of the atomic-openshift-utils package on each RHEL 7 system, which provides files that will be used in later sections:

# yum install atomic-openshift-utils

Install or update to the following latest available *-excluder packages on each RHEL 7 system, which helps ensure your systems stay on the correct versions of atomic-openshift and docker packages when you are not trying to upgrade, according to the OpenShift Container Platform version:

# yum install atomic-openshift-excluder atomic-openshift-docker-excluder

These packages add entries to the exclude directive in the host’s /etc/yum.conf file.

Create an etcd backup on each master. The etcd package is required, even if using embedded etcd, for access to the etcdctl command to make the backup. The package is installed by default for RHEL Atomic Host 7 systems. If the master is a RHEL 7 system, ensure the package is installed:

# yum install etcd

Then, create the backup:

# ETCD_DATA_DIR=/var/lib/origin/openshift.local.etcd
# etcdctl backup \
    --data-dir $ETCD_DATA_DIR \
    --backup-dir $ETCD_DATA_DIR.bak.<date>

This directory is for embedded etcd. For external etcd, use /var/lib/etcd instead.

Use the date of the backup, or some unique identifier, for <date>. The command will not make a backup if the --backup-dir location already exists.

For any upgrade path, ensure that you are running the latest kernel on each RHEL 7 system:

# yum update kernel

Upgrading Master Components

Upgrade your master hosts first:

Run the following command on each master to remove the atomic-openshift packages from the list of yum excludes on the host:

# atomic-openshift-excluder unexclude

Upgrade the atomic-openshift packages or related images.

For masters using the RPM-based method on a RHEL 7 system, upgrade all installed atomic-openshift packages:

# yum upgrade atomic-openshift\*

For masters using the containerized method on a RHEL 7 or RHEL Atomic Host 7 system, set the IMAGE_VERSION parameter to the version you are upgrading to in the following files:

/etc/sysconfig/atomic-openshift-master (single master clusters only)

/etc/sysconfig/atomic-openshift-master-controllers (multi-master clusters only)

/etc/sysconfig/atomic-openshift-master-api (multi-master clusters only)

/etc/sysconfig/atomic-openshift-node

/etc/sysconfig/atomic-openshift-openvswitch

For example:

IMAGE_VERSION=<tag>

Replace <tag> with v3.3.1.11 for the latest version.

In OpenShift Container Platform 3.3, protocol buffers are used by default for internal communications between node, masters, and controllers. To configure this, the following stanzas must be altered in the /etc/origin/master-config.yaml file on each master:

masterClients:
  externalKubernetesClientConnectionOverrides:
    acceptContentTypes: application/vnd.kubernetes.protobuf,application/json
    contentType: application/vnd.kubernetes.protobuf
    burst: 400
    qps: 200
  externalKubernetesKubeConfig: ""
  openshiftLoopbackClientConnectionOverrides:
    acceptContentTypes: application/vnd.kubernetes.protobuf,application/json
    contentType: application/vnd.kubernetes.protobuf
    burst: 600
    qps: 300
  openshiftLoopbackKubeConfig: openshift-master.kubeconfig

For more information on protocol buffers, see https://developers.google.com/protocol-buffers/docs/overview.

In OpenShift Container Platform 3.3, the kubernetesMasterConfig.admissionConfig.pluginConfig parameter in the /etc/origin/master-config.yaml file is being deprecated. If you are upgrading from version 3.2 to 3.3 and this parameter is in use, see General Admission Rules for guidance on moving and merging into admissionConfig.pluginConfig.

Restart the master service(s) on each master and review logs to ensure they restart successfully.

For single master clusters:

# systemctl restart atomic-openshift-master
# journalctl -r -u atomic-openshift-master

For multi-master clusters:

# systemctl restart atomic-openshift-master-controllers
# systemctl restart atomic-openshift-master-api
# journalctl -r -u atomic-openshift-master-controllers
# journalctl -r -u atomic-openshift-master-api

Because masters also have node components running on them in order to be configured as part of the OpenShift SDN, restart the atomic-openshift-node and openvswitch services:

# systemctl restart atomic-openshift-node
# systemctl restart openvswitch
# journalctl -r -u openvswitch
# journalctl -r -u atomic-openshift-node

Run the following command on each master to add the atomic-openshift packages back to the list of yum excludes on the host:

# atomic-openshift-excluder exclude

Upgrade any external etcd hosts using the RPM-based method on a RHEL 7 system:

Upgrade the etcd package:

# yum update etcd

Restart the etcd service and review the logs to ensure it restarts successfully:

# systemctl restart etcd
# journalctl -r -u etcd

Note

During the cluster upgrade, it can sometimes be useful to take a master out of rotation since some DNS client libraries will not properly to the other masters for cluster DNS. In addition to stopping the master and controller services, you can remove the EndPoint from the Kubernetes service’s subsets.addresses.

$ oc edit ep/kubernetes -n default

When the master is restarted, the Kubernetes service will be automatically updated.

Updating Policy Definitions

After a cluster upgrade, the recommended default cluster roles may be updated. To check if an update is recommended for your environment, you can run:

# oadm policy reconcile-cluster-roles

Warning

If you have customized default cluster roles and want to ensure a role reconciliation does not modify those customized roles, annotate them with openshift.io/reconcile-protect set to true. Doing so means you are responsible for manually updating those roles with any new or required permissions during upgrades.

This command outputs a list of roles that are out of date and their new proposed values. For example:

# oadm policy reconcile-cluster-roles
apiVersion: v1
items:
- apiVersion: v1
  kind: ClusterRole
  metadata:
    creationTimestamp: null
    name: admin
  rules:
  - attributeRestrictions: null
    resources:
    - builds/custom
...

Note

Your output will vary based on the OpenShift version and any local customizations you have made. Review the proposed policy carefully.

You can either modify this output to re-apply any local policy changes you have made, or you can automatically apply the new policy using the following process:

Reconcile the cluster roles:

# oadm policy reconcile-cluster-roles \
    --additive-only=true \
    --confirm

Reconcile the cluster role bindings:

# oadm policy reconcile-cluster-role-bindings \
    --exclude-groups=system:authenticated \
    --exclude-groups=system:authenticated:oauth \
    --exclude-groups=system:unauthenticated \
    --exclude-users=system:anonymous \
    --additive-only=true \
    --confirm

Reconcile security context constraints:

# oadm policy reconcile-sccs \
    --additive-only=true \
    --confirm

Upgrading Nodes

After upgrading your masters, you can upgrade your nodes. When restarting the atomic-openshift-node service, there will be a brief disruption of outbound network connectivity from running pods to services while the service proxy is restarted. The length of this disruption should be very short and scales based on the number of services in the entire cluster.

Note

Blue-green deployments are another proven approach to reducing downtime caused while updating an environment.

One at at time for each node that is not also a master, you must disable scheduling and evacuate its pods to other nodes, then upgrade packages and restart services.

Run the following command on each node to remove the atomic-openshift packages from the list of yum excludes on the host:

# atomic-openshift-excluder unexclude

As a user with cluster-admin privileges, disable scheduling for the node:

# oadm manage-node <node> --schedulable=false

Evacuate pods on the node to other nodes:

Important

The --force option deletes any pods that are not backed by a replication controller.

# oadm manage-node <node> --evacuate --force

Upgrade the node component packages or related images.

For nodes using the RPM-based method on a RHEL 7 system, upgrade all installed atomic-openshift packages:

# yum upgrade atomic-openshift\*

For nodes using the containerized method on a RHEL 7 or RHEL Atomic Host 7 system, set the IMAGE_VERSION parameter in the /etc/sysconfig/atomic-openshift-node and /etc/sysconfig/openvswitch files to the version you are upgrading to. For example:

IMAGE_VERSION=<tag>

Replace <tag> with v3.3.1.11 for the latest version.

In OpenShift Container Platform 3.3, protocol buffers are used by default for internal communications between node, masters, and controllers. To configure this, the following stanzas must be altered in the /etc/origin/node-config.yaml file on each node:

masterClientConnectionOverrides:
  acceptContentTypes: application/vnd.kubernetes.protobuf,application/json
  contentType: application/vnd.kubernetes.protobuf
  burst: 200
  qps: 100

For more information on protocol buffers, see https://developers.google.com/protocol-buffers/docs/overview.

Restart the atomic-openshift-node and openvswitch services and review the logs to ensure they restart successfully:

# systemctl restart atomic-openshift-node
# systemctl restart openvswitch
# journalctl -r -u atomic-openshift-node
# journalctl -r -u openvswitch

Re-enable scheduling for the node:

# oadm manage-node <node> --schedulable

Run the following command on the node to add the atomic-openshift packages back to the list of yum excludes on the host:

# atomic-openshift-excluder exclude

Repeat these steps on the next node, and continue repeating these steps until all nodes have been upgraded.

After all nodes have been upgraded, as a user with cluster-admin privileges, verify that all nodes are showing as Ready:

# oc get nodes
NAME                        STATUS                     AGE
master.example.com          Ready,SchedulingDisabled   165d
node1.example.com           Ready                      165d
node2.example.com           Ready                      165d

Upgrading the Router

If you have previously deployed a router, the router deployment configuration must be upgraded to apply updates contained in the router image. To upgrade your router without disrupting services, you must have previously deployed a highly-available routing service.

Note

If you previously customized your HAProxy routing template, then, depending on the changes, additional steps may be required due to changes in the routing data structure starting in OpenShift Container Platform 3.3. See Routing Data Structure Changes in the OpenShift Container Platform 3.3 Release Notes for details.

Edit your router’s deployment configuration. For example, if it has the default router name:

# oc edit dc/router

Apply the following changes:

...
spec:
 template:
    spec:
      containers:
      - env:
        ...
        image: registry.access.redhat.com/openshift3/ose-haproxy-router:<tag>
        imagePullPolicy: IfNotPresent
        ...

Adjust <tag> to match the version you are upgrading to (use v3.3.1.11 for the latest version).

You should see one router pod updated and then the next.

Upgrading the Registry

The registry must also be upgraded for changes to take effect in the registry image. If you have used a PersistentVolumeClaim or a host mount point, you may restart the registry without losing the contents of your registry. Storage for the Registry details how to configure persistent storage for the registry.

Edit your registry’s deployment configuration:

# oc edit dc/docker-registry

Apply the following changes:

...
spec:
 template:
    spec:
      containers:
      - env:
        ...
        image: registry.access.redhat.com/openshift3/ose-docker-registry:<tag>
        imagePullPolicy: IfNotPresent
        ...

Adjust <tag> to match the version you are upgrading to (use v3.3.1.11 for the latest version).

Important

Images that are being pushed or pulled from the internal registry at the time of upgrade will fail and should be restarted automatically. This will not disrupt pods that are already running.

Updating Custom Registry Configuration Files

Note

You may safely skip this part if you do not use a custom registry configuration file.

The internal Docker registry version 3.3.0 and higher requires following entries in the middleware section of the configuration file:

middleware:
  registry:
    - name: openshift
  repository:
    - name: openshift
  storage:
    - name: openshift

Edit your custom configuration file, adding the missing entries.

Deploy your updated configuration.

Append the --overwrite flag to oc volume dc/docker-registry --add to replace a volume mount of your previous secret.

You can safely remove the old secret.

Enforcing Quota in the Registry

Quota must be enforced to prevent layer blobs that exceed the size limit from being written to the registry’s storage. This can be achieved via a configuration file:

...
middleware:
  repository:
    - name: openshift
      options:
        enforcequota: true
...

Alternatively, use the REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_ENFORCEQUOTA environment variable, which is set to true for the new registry deployments by default. Existing deployments need to be modified using:

# oc set env dc/docker-registry REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_ENFORCEQUOTA=true

Updating the Default Image Streams and Templates

By default, the quick and advanced installation methods automatically create default image streams, InstantApp templates, and database service templates in the openshift project, which is a default project to which all users have view access. These objects were created during installation from the JSON files located under the /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/ directory.

Note

Because RHEL Atomic Host 7 cannot use yum to update packages, the following steps must take place on a RHEL 7 system.

Update the packages that provide the example JSON files. On a subscribed Red Hat Enterprise Linux 7 system where you can run the CLI as a user with cluster-admin permissions, install or update to the latest version of the atomic-openshift-utils package, which should also update the openshift-ansible- packages:

# yum update atomic-openshift-utils

The openshift-ansible-roles package provides the latest example JSON files.

Update the global openshift project by running the following commands. Receiving warnings about items that already exist is expected.

# oc create -n openshift -f /usr/share/openshift/examples/image-streams/image-streams-rhel7.json
# oc create -n openshift -f /usr/share/openshift/examples/image-streams/dotnet_imagestreams.json
# oc create -n openshift -f /usr/share/openshift/examples/db-templates
# oc create -n openshift -f /usr/share/openshift/examples/quickstart-templates
# oc create -n openshift -f /usr/share/openshift/examples/xpaas-streams
# oc create -n openshift -f /usr/share/openshift/examples/xpaas-templates
# oc replace -n openshift -f /usr/share/openshift/examples/image-streams/image-streams-rhel7.json
# oc replace -n openshift -f /usr/share/openshift/examples/db-templates
# oc replace -n openshift -f /usr/share/openshift/examples/quickstart-templates
# oc replace -n openshift -f /usr/share/openshift/examples/xpaas-streams
# oc replace -n openshift -f /usr/share/openshift/examples/xpaas-templates

After a manual upgrade, get the latest templates from openshift-ansible-roles:

rpm -ql openshift-ansible-roles | grep examples | grep v1.3

In this example, /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/image-streams/image-streams-rhel7.json is the latest file that you want in the latest openshift-ansible-roles package.

/usr/share/openshift/examples/image-streams/image-streams-rhel7.json is not owned by a package, but is updated by Ansible. If you are upgrading outside of Ansible. you need to get the latest .json files on the system where you are running oc, which can run anywhere that has access to the master.

Install atomic-openshift-utils and its dependencies to install the new content into /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/.:

$ oc create -n openshift -f  /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/image-streams/image-streams-rhel7.json
$ oc create -n openshift -f  /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/image-streams/dotnet_imagestreams.json
$ oc replace -n openshift -f  /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/image-streams/image-streams-rhel7.json
$ oc replace -n openshift -f  /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/image-streams/dotnet_imagestreams.json

Update the templates:

$ oc create -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/
$ oc create -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/db-templates/
$ oc create -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/infrastructure-templates/
$ oc create -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/xpaas-templates/
$ oc create -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/xpaas-streams/
$ oc replace -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/
$ oc replace -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/db-templates/
$ oc replace -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/infrastructure-templates/
$ oc replace -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/xpaas-templates/
$ oc replace -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/xpaas-streams/

Errors are generated for items that already exist. This is expected behavior:

# oc create -n openshift -f /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/
Error from server: error when creating "/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/cakephp-mysql.json": templates "cakephp-mysql-example" already exists
Error from server: error when creating "/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/cakephp.json": templates "cakephp-example" already exists
Error from server: error when creating "/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/dancer-mysql.json": templates "dancer-mysql-example" already exists
Error from server: error when creating "/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/dancer.json": templates "dancer-example" already exists
Error from server: error when creating "/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.3/quickstart-templates/django-postgresql.json": templates "django-psql-example" already exists

Now, content can be updated. Without running the automated upgrade playbooks, the content is not updated in /usr/share/openshift/.

Importing the Latest Images

After updating the default image streams, you may also want to ensure that the images within those streams are updated. For each image stream in the default openshift project, you can run:

# oc import-image -n openshift <imagestream>

For example, get the list of all image streams in the default openshift project:

# oc get is -n openshift
NAME     DOCKER REPO                                                      TAGS                   UPDATED
mongodb  registry.access.redhat.com/openshift3/mongodb-24-rhel7           2.4,latest,v3.1.1.6    16 hours ago
mysql    registry.access.redhat.com/openshift3/mysql-55-rhel7             5.5,latest,v3.1.1.6    16 hours ago
nodejs   registry.access.redhat.com/openshift3/nodejs-010-rhel7           0.10,latest,v3.1.1.6   16 hours ago
...

Update each image stream one at a time:

# oc import-image -n openshift nodejs
The import completed successfully.

Name:			nodejs
Created:		10 seconds ago
Labels:			<none>
Annotations:		openshift.io/image.dockerRepositoryCheck=2016-07-05T19:20:30Z
Docker Pull Spec:	172.30.204.22:5000/openshift/nodejs

Tag	Spec								Created		PullSpec						Image
latest	4								9 seconds ago	registry.access.redhat.com/rhscl/nodejs-4-rhel7:latest	570ad8ed927fd5c2c9554ef4d9534cef808dfa05df31ec491c0969c3bd372b05
4	registry.access.redhat.com/rhscl/nodejs-4-rhel7:latest		9 seconds ago	<same>							570ad8ed927fd5c2c9554ef4d9534cef808dfa05df31ec491c0969c3bd372b05
0.10	registry.access.redhat.com/openshift3/nodejs-010-rhel7:latest	9 seconds ago	<same>							a1ef33be788a28ec2bdd48a9a5d174ebcfbe11c8e986d2996b77f5bccaaa4774

Important

In order to update your S2I-based applications, you must manually trigger a new build of those applications after importing the new images using oc start-build <app-name>.

Upgrading the EFK Logging Stack

Use the following to upgrade an already-deployed EFK logging stack.

Note

The following steps apply when upgrading to OpenShift Container Platform 3.3+.

Ensure you are working in the project where the EFK stack was previously deployed. For example, if the project is named logging:

$ oc project logging

Recreate the deployer templates for service accounts and running the deployer:

$ oc apply -n openshift -f \
    /usr/share/openshift/examples/infrastructure-templates/enterprise/logging-deployer.yaml

Generate any missing service accounts and roles:

$ oc process logging-deployer-account-template | oc apply -f -

Ensure that the cluster role oauth-editor is assigned to the logging-deployer service account:

$ oadm policy add-cluster-role-to-user oauth-editor \
       system:serviceaccount:logging:logging-deployer

In preparation for running the deployer, ensure that you have the configurations for your current deployment in the logging-deployer ConfigMap.

Important

Ensure that your image version is the latest version, not the currently installed version.

Run the deployer with the parameter in upgrade mode:

$ oc new-app logging-deployer-template -p MODE=upgrade

Running the deployer in this mode handles scaling down the components to minimize loss of logs, patching configurations, generating missing secrets and keys, and scaling the components back up to their previous replica count.

Important

Due to the privileges needed to label and unlabel a node for controlling the deployment of Fluentd pods, the deployer does delete the logging-fluentd Daemonset and recreates it from the logging-fluentd-template template.

Upgrading Cluster Metrics

After upgrading an already-deployed Cluster Metrics install, you must update to a newer version of the metrics components.

The update process stops all the metrics containers, updates the metrics configuration files, and redeploys the newer components.

It does not change the metrics route.

It does not delete the metrics persistent volume claim. Metrics stored to persistent volumes before the update are available after the update completes.

Important

The update deletes all non-persisted metric values and overwrites local changes to the metrics configurations. For example, the number of instances in a replica set is not saved.

To update, follow the same steps as when the metrics components were first deployed, using the correct template, except this time, specify the MODE=refresh option:

$ oc new-app -f metrics-deployer.yaml \
    -p HAWKULAR_METRICS_HOSTNAME=hm.example.com,MODE=refresh

In the original deployment command, there was no MODE=refresh.

Note

During the update, the metrics components do not run. Because of this, they cannot collect data and a gap normally appears in the graphs.

Additional Manual Steps Per Release

Some OpenShift Container Platform releases may have additional instructions specific to that release that must be performed to fully apply the updates across the cluster. This section will be updated over time as new asynchronous updates are released for OpenShift Container Platform 3.3.

As of the latest 3.3 release (v3.3.1.11), there are no 3.3 asynchronous releases that require additional instructions during upgrade. See the OpenShift Container Platform 3.3 Release Notes to review the latest release notes.

Verifying the Upgrade

To verify the upgrade, first check that all nodes are marked as Ready:

# oc get nodes
NAME                        STATUS                     AGE
master.example.com          Ready,SchedulingDisabled   165d
node1.example.com           Ready                      165d
node2.example.com           Ready                      165d

Then, verify that you are running the expected versions of the docker-registry and router images, if deployed. Replace <tag> with v3.3.1.11 for the latest version.

# oc get -n default dc/docker-registry -o json | grep \"image\"
    "image": "openshift3/ose-docker-registry:<tag>",
# oc get -n default dc/router -o json | grep \"image\"
    "image": "openshift3/ose-haproxy-router:<tag>",

After upgrading, you can use the diagnostics tool on the master to look for common issues:

# oadm diagnostics
...
[Note] Summary of diagnostics execution:
[Note] Completed with no errors or warnings seen.

Blue-Green Deployments

Overview

Note

This topic serves as an alternative node upgrade method to the approach in Manual In-place Upgrades.

Blue-green deployments are a proven approach to reducing downtime caused while upgrading an environment. This is done by creating a parallel environment on which the new deployment can be installed. If a problem is detected, and after the new deployment is verified, traffic can be switched over with the option to rollback.

While blue-green is a valid strategy for deploying just about any software, there are always trade-offs. Not all environments have the same uptime requirements or the resources to properly perform blue-green deployments. In an OpenShift Container Platform environment, the most suitable candidate for blue-green deployments are the nodes. All user processes run on these systems and even critical pieces of OpenShift Container Platform infrastructure are self-hosted there. Uptime is most important for these workloads and the additional complexity of blue-green deployments can be justified. The exact implementation of this approach varies based on your requirements. Often the main challenge is having the excess capacity to facilitate such an approach.

Another lesser challenge is that the administrator must temporarily share the Red Hat software entitlements between the blue-green deployments or provide access to the installation content by means of a system such as Red Hat Satellite. This can be accomplished by sharing the consumer ID from the previous host.

Preparing for Upgrade

On the old host:

# subscription-manager identity | grep system
system identity: 6699375b-06db-48c4-941e-689efd6ce3aa

On the new host:

# subscription-manager register --consumerid=6699375b-06db-48c4-941e-689efd6ce3aa

Important

After a successful deployment, remember to unregister the old host with subscription-manager clean to prevent the environment from being out of compliance.

After the master and etcd servers have been upgraded, you must ensure that your current production nodes are labeled either blue or green. In this example, the current installation will be blue and the new environment will be green. On each production node in your current installation:

$ oc label --all nodes color=blue

In the case of nodes requiring the uptime guarantees of a blue-green deployment, the -l flag can be used to match a subset of the environment using a selector.

Create the new green environment for any nodes that are to be replaced by adding an equal number of new nodes to the existing cluster. Ansible can apply the color=green label using the openshift_node_labels variable for each node.

In order to delay workload scheduling until the nodes are healthy, be sure to set the openshift_schedulable=false variable. After the green nodes are in Ready state, they can be made schedulable.

Blue nodes are disabled so that no new pods are run on them:

# oadm manage-node --schedulable=true --selector=color=green
# oadm manage-node --schedulable=false --selector=color=blue

A common practice is to scale the registry and router pods until they are migrated to the green nodes. For these pods, a canary deployment approach is commonly used. Scaling them up will make them immediately active on the new nodes. Pointing the deployment configuration to the new image initiates a rolling update. However, because of node anti-affinity, and the fact that the blue nodes are still unschedulable, the deployments to the old nodes will fail. At this point, the registry and router deployments can be scaled down to the original number of pods. At any given point, the original number of pods is still available so no capacity is lost.

Warming the New Nodes

In order for pods to be migrated from the blue environment to the green, the images must be pulled. Network latency and load on the registry can cause delays if there is not sufficient capacity built in to the environment. Often, the best way to minimize impact to the running system is to trigger new pod deployments that will land on the new nodes. Accomplish this by importing new image streams.

A major release of OpenShift Container Platform is the motivation for a blue-green deployment. At that time, new image streams become available for users of Source-to-Image (S2I). Upon import, any builds or deployments configured with ImageChangeTriggers are automatically created.

Note

To continue with the upgrade process, update the default image streams and templates and import the latest images.

It is important to realize that this process can trigger a large number of builds. The good news is that the builds are performed on the green nodes and, therefore, do not impact any traffic on the blue deployment.

To monitor build progress across all namespaces (projects) in the cluster:

$ oc get events -w --all-namespaces

In large environments, builds rarely completely stop. However, you should see a large increase and decrease caused by the administrative import.

Another benefit of triggering the builds is that it does a fairly good job of fetching the majority of the ancillary images to all nodes such as the various build images, the pod infrastructure image, and deployers. Everything else can be moved over using node evacuation and will proceed more quickly as a result.

Node Evacuation

For larger deployments, it is possible to have other labels that help determine how evacuation can be coordinated. The most conservative approach for avoiding downtime is to evacuate one node at a time. If services are composed of pods using zone anti-affinity, then an entire zone can be evacuated at once. It is important to ensure that the storage volumes used are available in the new zone as this detail can vary among cloud providers.

In OpenShift Enterprise 3.2 and later, a node evacuation is triggered whenever the service is stopped. Achieve manual evacuation and deletion of all blue nodes at once by:

# oadm manage-node --selector=color=blue --evacuate
# oc delete node --selector=color=blue

Operating System Updates and Upgrades

Impacts

When updating or upgrading your operating system (OS), either changing OS versions or updating the system software, be aware that this can impact the OpenShift Container Platform software running on those machines. In particular, these updates can affect the iptables rules or ovs flows that OpenShift Container Platform requires to operate.

Solutions

Reboot the node to ensure that all of the software is running the new versions, especially if a new kernel is installed. A reboot will also ensure that the docker and OpenShift Container Platform processes have been restarted, which will force them to check that all of the rules in other services are correct.

However, if you do not wish to do a reboot of the node, then it is possible to just restart the services that are affected, or to preserve the iptables state. Both processes are described in the OpenShift Container Platform IPtables topic. The ovs flow rules do not need to be saved, but restarting the OpenShift Container Platform node software will fix the flow rules.

Chapter 6. Downgrading OpenShift

Overview

Following an OpenShift Container Platform upgrade, it may be desirable in extreme cases to downgrade your cluster to a previous version. The following sections outline the required steps for each system in a cluster to perform such a downgrade for the OpenShift Container Platform 3.2 to 3.1 downgrade path.

Warning

These steps are currently only supported for RPM-based installations of OpenShift Container Platform and assumes downtime of the entire cluster.

Important

For the OpenShift Container Platform 3.1 to 3.0 downgrade path, see the OpenShift Enterprise 3.1 documentation, which has modified steps.

Verifying Backups

The Ansible playbook used during the upgrade process should have created a backup of the master-config.yaml file and the etcd data directory. Ensure these exist on your masters and etcd members:

/etc/origin/master/master-config.yaml.<timestamp>
/var/lib/origin/etcd-backup-<timestamp>

Also, back up the node-config.yaml file on each node (including masters, which have the node component on them) with a timestamp:

/etc/origin/node/node-config.yaml.<timestamp>

If you are using an external etcd cluster (versus the single embedded etcd), the backup is likely created on all etcd members, though only one is required for the recovery process.

The RPM downgrade process in a later step should create .rpmsave backups of the following files, but it may be a good idea to keep a separate copy regardless:

/etc/sysconfig/atomic-openshift-master
/etc/etcd/etcd.conf

Only required if using external etcd.

Shutting Down the Cluster

On all masters, nodes, and etcd members (if using an external etcd cluster), ensure the relevant services are stopped.

On the master in a single master cluster:

# systemctl stop atomic-openshift-master

On each master in a multi-master cluster:

# systemctl stop atomic-openshift-master-api
# systemctl stop atomic-openshift-master-controllers

On all master and node hosts:

# systemctl stop atomic-openshift-node

On any external etcd hosts:

# systemctl stop etcd

Removing RPMs

On all masters, nodes, and etcd members (if using an external etcd cluster), remove the following packages:

# yum remove atomic-openshift \
    atomic-openshift-clients \
    atomic-openshift-node \
    atomic-openshift-master \
    openvswitch \
    atomic-openshift-sdn-ovs \
    tuned-profiles-atomic-openshift-node

If you are using external etcd, also remove the etcd package:

# yum remove etcd

For embedded etcd, you can leave the etcd package installed, as the package is only required so that the etcdctl command is available to issue operations in later steps.

Downgrading Docker

OpenShift Container Platform 3.2 requires Docker 1.9.1 and also supports Docker 1.10.3, however OpenShift Container Platform 3.1 requires Docker 1.8.2.

Downgrade to Docker 1.8.2 on each host using the following steps:

Remove all local containers and images on the host. Any pods backed by a replication controller will be recreated.

Warning

The following commands are destructive and should be used with caution.

Delete all containers:

# docker rm $(docker ps -a -q)

Delete all images:

# docker rmi $(docker images -q)

Use yum swap (instead of yum downgrade) to install Docker 1.8.2:

# yum swap docker-* docker-*1.8.2
# sed -i 's/--storage-opt dm.use_deferred_deletion=true//' /etc/sysconfig/docker-storage
# systemctl restart docker

You should now have Docker 1.8.2 installed and running on the host. Verify with the following:

# docker version
Client:
 Version:      1.8.2-el7
 API version:  1.20
 Package Version: docker-1.8.2-10.el7.x86_64
[...]

# systemctl status docker
● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor preset: disabled)
   Active: active (running) since Mon 2016-06-27 15:44:20 EDT; 33min ago
[...]

Reinstalling RPMs

Disable the OpenShift Container Platform 3.3 repositories, and re-enable the 3.2 repositories:

# subscription-manager repos \
    --disable=rhel-7-server-ose-3.3-rpms \
    --enable=rhel-7-server-ose-3.2-rpms

On each master, install the following packages:

# yum install atomic-openshift \
    atomic-openshift-clients \
    atomic-openshift-node \
    atomic-openshift-master \
    openvswitch \
    atomic-openshift-sdn-ovs \
    tuned-profiles-atomic-openshift-node

On each node, install the following packages:

# yum install atomic-openshift \
    atomic-openshift-node \
    openvswitch \
    atomic-openshift-sdn-ovs \
    tuned-profiles-atomic-openshift-node

If using an external etcd cluster, install the following package on each etcd member:

# yum install etcd

Restoring etcd

Whether using embedded or external etcd, you must first restore the etcd backup by creating a new, single node etcd cluster. If using external etcd with multiple members, you must then also add any additional etcd members to the cluster one by one.

However, the details of the restoration process differ between embedded and external etcd. See the following section that matches your etcd configuration and follow the relevant steps before continuing to Bringing OpenShift Container Platform Services Back Online.

Follow the Cluster Restore procedure to restore single-member etcd clusters.

Embedded etcd

Restore your etcd backup and configuration:

Run the following on the master with the embedded etcd:

# ETCD_DIR=/var/lib/origin/openshift.local.etcd
# mv $ETCD_DIR /var/lib/etcd.orig
# cp -Rp /var/lib/origin/etcd-backup-<timestamp>/ $ETCD_DIR
# chcon -R --reference /var/lib/etcd.orig/ $ETCD_DIR
# chown -R etcd:etcd $ETCD_DIR

Warning

The $ETCD_DIR location differs between external and embedded etcd.

Create the new, single node etcd cluster:

# etcd -data-dir=/var/lib/origin/openshift.local.etcd \
    -force-new-cluster

Verify etcd has started successfully by checking the output from the above command, which should look similar to the following near the end:

[...]
2016-06-24 12:14:45.644073 I | etcdserver: starting server... [version: 2.2.5, cluster version: 2.2]
[...]
2016-06-24 12:14:46.834394 I | etcdserver: published {Name:default ClientURLs:[http://localhost:2379 http://localhost:4001]} to cluster 5580663a6e0002

Shut down the process by running the following from a separate terminal:

# pkill etcd

Continue to Bringing OpenShift Container Platform Services Back Online.

External etcd

Choose a system to be the initial etcd member, and restore its etcd backup and configuration:

Run the following on the etcd host:

# ETCD_DIR=/var/lib/etcd/
# mv $ETCD_DIR /var/lib/etcd.orig
# cp -Rp /var/lib/origin/etcd-backup-<timestamp>/ $ETCD_DIR
# chcon -R --reference /var/lib/etcd.orig/ $ETCD_DIR
# chown -R etcd:etcd $ETCD_DIR

Warning

The $ETCD_DIR location differs between external and embedded etcd.

Restore your /etc/etcd/etcd.conf file from backup or .rpmsave.

Create the new single node cluster using etcd’s --force-new-cluster option. You can do this with a long complex command using the values from /etc/etcd/etcd.conf, or you can temporarily modify the systemd unit file and start the service normally.

To do so, edit the /usr/lib/systemd/system/etcd.service and add --force-new-cluster:

# sed -i '/ExecStart/s/"$/  --force-new-cluster"/' /usr/lib/systemd/system/etcd.service
# cat /usr/lib/systemd/system/etcd.service  | grep ExecStart

ExecStart=/bin/bash -c "GOMAXPROCS=$(nproc) /usr/bin/etcd --force-new-cluster"

Then restart the etcd service:

# systemctl daemon-reload
# systemctl start etcd

Verify the etcd service started correctly, then re-edit the /usr/lib/systemd/system/etcd.service file and remove the --force-new-cluster option:

# sed -i '/ExecStart/s/ --force-new-cluster//' /usr/lib/systemd/system/etcd.service
# cat /usr/lib/systemd/system/etcd.service  | grep ExecStart

ExecStart=/bin/bash -c "GOMAXPROCS=$(nproc) /usr/bin/etcd"

Restart the etcd service, then verify the etcd cluster is running correctly and displays OpenShift Container Platform’s configuration:

# systemctl daemon-reload
# systemctl restart etcd
# etcdctl --cert-file=/etc/etcd/peer.crt \
    --key-file=/etc/etcd/peer.key \
    --ca-file=/etc/etcd/ca.crt \
    --peers="https://172.16.4.18:2379,https://172.16.4.27:2379" \
    ls /

If you have additional etcd members to add to your cluster, continue to Adding Additional etcd Members. Otherwise, if you only want a single node external etcd, continue to Bringing OpenShift Container Platform Services Back Online.

Adding Additional etcd Members

To add additional etcd members to the cluster, you must first adjust the default localhost peer in the peerURLs value for the first member:

Get the member ID for the first member using the member list command:

# etcdctl --cert-file=/etc/etcd/peer.crt \
    --key-file=/etc/etcd/peer.key \
    --ca-file=/etc/etcd/ca.crt \
    --peers="https://172.18.1.18:2379,https://172.18.9.202:2379,https://172.18.0.75:2379" \
    member list

Update the value of peerURLs using the etcdctl member update command by passing the member ID obtained from the previous step:

# etcdctl --cert-file=/etc/etcd/peer.crt \
    --key-file=/etc/etcd/peer.key \
    --ca-file=/etc/etcd/ca.crt \
    --peers="https://172.18.1.18:2379,https://172.18.9.202:2379,https://172.18.0.75:2379" \
    member update 511b7fb6cc0001 https://172.18.1.18:2380

Alternatively, you can use curl:

# curl --cacert /etc/etcd/ca.crt \
    --cert /etc/etcd/peer.crt \
    --key /etc/etcd/peer.key \
    https://172.18.1.18:2379/v2/members/511b7fb6cc0001 \
    -XPUT -H "Content-Type: application/json" \
    -d '{"peerURLs":["https://172.18.1.18:2380"]}'

Re-run the member list command and ensure the peer URLs no longer include localhost.

Now add each additional member to the cluster, one at a time.

Warning

Each member must be fully added and brought online one at a time. When adding each additional member to the cluster, the peerURLs list must be correct for that point in time, so it will grow by one for each member added. The etcdctl member add command will output the values that need to be set in the etcd.conf file as you add each member, as described in the following instructions.

For each member, add it to the cluster using the values that can be found in that system’s etcd.conf file:

# etcdctl --cert-file=/etc/etcd/peer.crt \
    --key-file=/etc/etcd/peer.key \
    --ca-file=/etc/etcd/ca.crt \
    --peers="https://172.16.4.18:2379,https://172.16.4.27:2379" \
    member add 10.3.9.222 https://172.16.4.27:2380

Added member named 10.3.9.222 with ID 4e1db163a21d7651 to cluster

ETCD_NAME="10.3.9.222"
ETCD_INITIAL_CLUSTER="10.3.9.221=https://172.16.4.18:2380,10.3.9.222=https://172.16.4.27:2380"
ETCD_INITIAL_CLUSTER_STATE="existing"

Using the environment variables provided in the output of the above etcdctl member add command, edit the /etc/etcd/etcd.conf file on the member system itself and ensure these settings match.

Now start etcd on the new member:

# rm -rf /var/lib/etcd/member
# systemctl enable etcd
# systemctl start etcd

Ensure the service starts correctly and the etcd cluster is now healthy:

# etcdctl --cert-file=/etc/etcd/peer.crt \
    --key-file=/etc/etcd/peer.key \
    --ca-file=/etc/etcd/ca.crt \
    --peers="https://172.16.4.18:2379,https://172.16.4.27:2379" \
    member list

51251b34b80001: name=10.3.9.221 peerURLs=https://172.16.4.18:2380 clientURLs=https://172.16.4.18:2379
d266df286a41a8a4: name=10.3.9.222 peerURLs=https://172.16.4.27:2380 clientURLs=https://172.16.4.27:2379

# etcdctl --cert-file=/etc/etcd/peer.crt \
    --key-file=/etc/etcd/peer.key \
    --ca-file=/etc/etcd/ca.crt \
    --peers="https://172.16.4.18:2379,https://172.16.4.27:2379" \
    cluster-health

cluster is healthy
member 51251b34b80001 is healthy
member d266df286a41a8a4 is healthy

Now repeat this process for the next member to add to the cluster.

After all additional etcd members have been added, continue to Bringing OpenShift Container Platform Services Back Online.

Bringing OpenShift Container Platform Services Back Online

On each OpenShift Container Platform master, restore your master and node configuration from backup and enable and restart all relevant services.

On the master in a single master cluster:

# cp /etc/sysconfig/atomic-openshift-master.rpmsave /etc/sysconfig/atomic-openshift-master
# cp /etc/origin/master/master-config.yaml.<timestamp> /etc/origin/master/master-config.yaml
# cp /etc/origin/node/node-config.yaml.<timestamp> /etc/origin/node/node-config.yaml
# systemctl enable atomic-openshift-master
# systemctl enable atomic-openshift-node
# systemctl start atomic-openshift-master
# systemctl start atomic-openshift-node

On each master in a multi-master cluster:

# cp /etc/sysconfig/atomic-openshift-master-api.rpmsave /etc/sysconfig/atomic-openshift-master-api
# cp /etc/sysconfig/atomic-openshift-master-controllers.rpmsave /etc/sysconfig/atomic-openshift-master-controllers
# cp /etc/origin/master/master-config.yaml.<timestamp> /etc/origin/master/master-config.yaml
# cp /etc/origin/node/node-config.yaml.<timestamp> /etc/origin/node/node-config.yaml
# systemctl enable atomic-openshift-master-api
# systemctl enable atomic-openshift-master-controllers
# systemctl enable atomic-openshift-node
# systemctl start atomic-openshift-master-api
# systemctl start atomic-openshift-master-controllers
# systemctl start atomic-openshift-node

On each OpenShift Container Platform node, restore your node-config.yaml file from backup and enable and restart the atomic-openshift-node service:

# cp /etc/origin/node/node-config.yaml.<timestamp> /etc/origin/node/node-config.yaml
# systemctl enable atomic-openshift-node
# systemctl start atomic-openshift-node

Your OpenShift Container Platform cluster should now be back online.

Verifying the Downgrade

To verify the downgrade, first check that all nodes are marked as Ready:

# oc get nodes
NAME                        STATUS                     AGE
master.example.com          Ready,SchedulingDisabled   165d
node1.example.com           Ready                      165d
node2.example.com           Ready                      165d

Then, verify that you are running the expected versions of the docker-registry and router images, if deployed:

# oc get -n default dc/docker-registry -o json | grep \"image\"
    "image": "openshift3/ose-docker-registry:v3.1.1.6",
# oc get -n default dc/router -o json | grep \"image\"
    "image": "openshift3/ose-haproxy-router:v3.1.1.6",

You can use the diagnostics tool on the master to look for common issues and provide suggestions. In OpenShift Container Platform 3.1, the oc adm diagnostics tool is available as openshift ex diagnostics:

# openshift ex diagnostics
...
[Note] Summary of diagnostics execution:
[Note] Completed with no errors or warnings seen.

Chapter 7. Master and Node Configuration

Overview

The openshift start command is used to launch OpenShift Container Platform servers. The command and its subcommands (master to launch a master server and node to launch a node server) all take a limited set of arguments that are sufficient for launching servers in a development or experimental environment.

However, these arguments are insufficient to describe and control the full set of configuration and security options that are necessary in a production environment. To provide those options, it is necessary to use the dedicated master and node configuration files.

Master configuration files and node configuration files are fully specified with no default values. Therefore, any empty value indicates that you want to start up with an empty value for that parameter. This makes it easy to reason about exactly what your configuration is, but it also makes it difficult to remember all of the options to specify. To make this easier, the configuration files can be created with the --write-config option and then used with the --config option.

Master Configuration Files

This section reviews parameters mentioned in the master-config.yaml file.

You can create a new master configuration file to see the valid options for your installed version of OpenShift Container Platform.

Admission Control Configuration

Table 7.1. Admission Control Configuration Parameters

Parameter Name
Description

AdmissionConfig

Contains admission control plug-in configuration.

APIServerArguments

Key-value pairs that will be passed directly to the Kube API server that match the API servers' command line arguments. These are not migrated, but if you reference a value that does not exist the server will not start. These values may override other settings in KubernetesMasterConfig, which may cause invalid configurations.

ControllerArguments

Key-value pairs that will be passed directly to the Kube controller manager that match the controller manager’s command line arguments. These are not migrated, but if you reference a value that does not exist the server will not start. These values may override other settings in KubernetesMasterConfig, which may cause invalid configurations.

DefaultAdmissionConfig

Used to enable or disable various admission plug-ins. When this type is present as the configuration object under pluginConfig and if the admission plug-in supports it, this will cause an off by default admission plug-in to be enabled.

PluginConfig

Allows specifying a configuration file per admission control plug-in.

PluginOrderOverride

A list of admission control plug-in names that will be installed on the master. Order is significant. If empty, a default list of plug-ins is used.

SchedulerArguments

Key-value pairs that will be passed directly to the Kube scheduler that match the scheduler’s command line arguments. These are not migrated, but if you reference a value that does not exist the server will not start. These values may override other settings in KubernetesMasterConfig, which may cause invalid configurations.

Asset Configuration

Table 7.2. Asset Configuration Parameters

Parameter Name
Description

AssetConfig

Holds the necessary configuration options for serving assets.

DisabledFeatures

A list of features that should not be started. You will likely want to set this as null. It is very unlikely that anyone will want to manually disable features and that is not encouraged.

Extensions

Files to serve from the asset server file system under a subcontext.

ExtensionDevelopment

When set to true, tells the asset server to reload extension scripts and stylesheets for every request rather than only at startup. It lets you develop extensions without having to restart the server for every change.

ExtensionProperties

Key- (string) and value- (string) pairs that will be injected into the console under the global variable OPENSHIFT_EXTENSION_PROPERTIES.

ExtensionScripts

File paths on the asset server files to load as scripts when the web console loads.

ExtensionStylesheets

File paths on the asset server files to load as style sheets when the web console loads.

LoggingPublicURL

The public endpoint for logging (optional).

LogoutURL

An optional, absolute URL to redirect web browsers to after logging out of the web console. If not specified, the built-in logout page is shown.

MasterPublicURL

How the web console can access the OpenShift Container Platform server.

MetricsPublicURL

The public endpoint for metrics (optional).

PublicURL

URL of the the asset server.

Authentication and Authorization Configuration

Table 7.3. Authentication and Authorization Parameters

Parameter Name
Description

authConfig

Holds authentication and authorization configuration options.

AuthenticationCacheSize

Indicates how many authentication results should be cached. If 0, the default cache size is used.

AuthorizationCacheTTL

Indicates how long an authorization result should be cached. It takes a valid time duration string (e.g. "5m"). If empty, you get the default timeout. If zero (e.g. "0m"), caching is disabled.

Controller Configuration

Table 7.4. Controller Configuration Parameters

Parameter Name
Description

Controllers

List of the controllers that should be started. If set to none, no controllers will start automatically. The default value is * which will start all controllers. When using *, you may exclude controllers by prepending a - in front of their name. No other values are recognized at this time.

ControllerLeaseTTL

Enables controller election, instructing the master to attempt to acquire a lease before controllers start and renewing it within a number of seconds defined by this value. Setting this value non-negative forces pauseControllers=true. This value defaults off (0, or omitted) and controller election can be disabled with -1.

PauseControllers

Instructs the master to not automatically start controllers, but instead to wait until a notification to the server is received before launching them.

etcd Configuration

Table 7.5. etcd Configuration Parameters

Parameter Name
Description

Address

The advertised host:port for client connections to etcd.

etcdClientInfo

Contains information about how to connect to etcd.

etcdConfig

Holds the necessary configuration options for connecting with an etcd database.

etcdStorageConfig

Contains information about how API resources are stored in etcd. These values are only relevant when etcd is the backing store for the cluster.

KubernetesStoragePrefix

The path within etcd that the Kubernetes resources will be rooted under. This value, if changed, will mean existing objects in etcd will no longer be located. The default value is kubernetes.io.

KubernetesStorageVersion

The API version that Kubernetes resources in etcd should be serialized to. This value should not be advanced until all clients in the cluster that read from etcd have code that allows them to read the new version.

OpenShiftStoragePrefix

The path within etcd that the OpenShift Container Platform resources will be rooted under. This value, if changed, will mean existing objects in etcd will no longer be located. The default value is openshift.io.

OpenShiftStorageVersion

API version that OS resources in etcd should be serialized to. This value should not be advanced until all clients in the cluster that read from etcd have code that allows them to read the new version.

PeerAddress

The advertised host:port for peer connections to etcd.

PeerServingInfo

Describes how to start serving the etcd peer.

ServingInfo

Describes how to start serving the etcd master.

StorageDir

The path to the etcd storage directory.

Grant Configuration

Table 7.6. Grant Configuration Parameters

Parameter Name
Description

GrantConfig

Describes how to handle grants.

GrantHandlerAuto

Auto-approves client authorization grant requests.

GrantHandlerDeny

Auto-denies client authorization grant requests.

GrantHandlerPrompt

Prompts the user to approve new client authorization grant requests.

Method

Determines the default strategy to use when an OAuth client requests a grant.This method will be used only if the specific OAuth client does not provide a strategy of their own. Valid grant handling methods are:

auto: always approves grant requests, useful for trusted clients

prompt: prompts the end user for approval of grant requests, useful for third-party clients

deny: always denies grant requests, useful for black-listed clients

Image Configuration

Table 7.7. Image Configuration Parameters

Parameter Name
Description

DisableScheduledImport

Allows scheduled background import of images to be disabled.

Format

The format of the name to be built for the system component.

ImageConfig

Holds options that describe how to build image names for system components.

ImagePolicyConfig

Controls limits and behavior for importing images.

Latest

Determines if the latest tag will be pulled from the registry.

MaxImagesBulkImportedPerRepository

Controls the number of images that are imported when a user does a bulk import of a Docker repository. This number defaults to 5 to prevent users from importing large numbers of images accidentally. Set -1 for no limit.

MaxScheduledImageImportsPerMinute

The maximum number of scheduled image streams that will be imported in the background per minute. The default value is 60. Set to -1 for unlimited.

ScheduledImageImportMinimumIntervalSeconds

The minimum number of seconds that can elapse between when image streams scheduled for background import are checked against the upstream repository. The default value is 15 minutes.

Kubernetes Master Configuration

Table 7.8. Kubernetes Master Configuration Parameters

Parameter Name
Description

APILevels

A list of API levels that should be enabled on startup, v1 as examples.

DisabledAPIGroupVersions

A map of groups to the versions (or *) that should be disabled.

KubeletClientInfo

Contains information about how to connect to kubelets.

KubernetesMasterConfig

Holds the necessary configuration options for the Kubernetes master.

MasterCount

The number of expected masters that should be running. This value defaults to 1 and may be set to a positive integer, or if set to -1, indicates this is part of a cluster.

MasterIP

The public IP address of Kubernetes resources. If empty, the first result from net.InterfaceAddrs will be used.

MasterKubeConfig

File name for the .kubeconfig file that describes how to connect this node to the master.

ServicesNodePortRange

The range to use for assigning service public ports on a host.

ServicesSubnet

The subnet to use for assigning service IPs.

StaticNodeNames

The list of nodes that are statically known.

Network Configuration

Table 7.9. Network Configuration Parameters

Parameter Name
Description

ClusterNetworkCIDR

The CIDR string to specify the global overlay network’s L3 space.

ExternalIPNetworkCIDRs

Controls what values are acceptable for the service external IP field. If empty, no externalIP may be set. It may contain a list of CIDRs which are checked for access. If a CIDR is prefixed with !, IPs in that CIDR will be rejected. Rejections will be applied first, then the IP checked against one of the allowed CIDRs. You hould ensure this range does not overlap with your nodes, pods, or service CIDRs for security reasons.

HostSubnetLength

The number of bits to allocate to each host’s subnet. For example, 8 would mean a /24 network on the host.

IngressIPNetworkCIDR

Controls the range to assign ingress IPs from for services of type LoadBalancer on bare metal. If empty, ingress IPs will not be assigned. It may contain a single CIDR that will be allocated from. For security reasons, you should ensure that this range does not overlap with the CIDRs reserved for external IPs, nodes, pods, or services.

NetworkConfig

Provides network options for the node.

NetworkPluginName

The name of the network plug-in to use.

ServiceNetwork

The CIDR string to specify the service networks.

OAuth Authentication Configuration

Table 7.10. OAuth Configuration Parameters

Parameter Name
Description

AlwaysShowProviderSelection

Forces the provider selection page to render even when there is only a single provider.

AssetPublicURL

Used for building valid client redirect URLs for external access.

Error

A path to a file containing a go template used to render error pages during the authentication or grant flow If unspecified, the default error page is used.

IdentityProviders

Ordered list of ways for a user to identify themselves.

Login

A path to a file containing a go template used to render the login page. If unspecified, the default login page is used.

MasterCA

CA for verifying the TLS connection back to the MasterURL.

MasterPublicURL

Used for building valid client redirect URLs for external access.

MasterURL

Used for making server-to-server calls to exchange authorization codes for access tokens.

OAuthConfig

Holds the necessary configuration options for OAuth authentication.

OAuthTemplates

Allows for customization of pages like the login page.

ProviderSelection

A path to a file containing a go template used to render the provider selection page. If unspecified, the default provider selection page is used.

SessionConfig

Holds information about configuring sessions.

Templates

Allows you to customize pages like the login page.

TokenConfig

Contains options for authorization and access tokens.

Project Configuration

Table 7.11. Project Configuration Parameters

Parameter Name
Description

DefaultNodeSelector

Holds default project node label selector.

ProjectConfig

Holds information about project creation and defaults.

ProjectRequestMessage

The string presented to a user if they are unable to request a project via the project request API endpoint.

ProjectRequestTemplate

The template to use for creating projects in response to projectrequest. It is in the format namespace/template and it is optional. If it is not specified, a default template is used.

Scheduler Configuration

Table 7.12. Scheduler Configuration Parameters

Parameter Name
Description

SchedulerConfigFile

Points to a file that describes how to set up the scheduler. If empty, you get the default scheduling rules

Security Allocator Configuration

Table 7.13. Security Allocator Parameters

Parameter Name
Description

MCSAllocatorRange

Defines the range of MCS categories that will be assigned to namespaces. The format is <prefix>/<numberOfLabels>[,<maxCategory>]. The default is s0/2 and will allocate from c0 to c1023, which means a total of 535k labels are available (1024 choose 2 ~ 535k). If this value is changed after startup, new projects may receive labels that are already allocated to other projects. Prefix may be any valid SELinux set of terms (including user, role, and type), although leaving them as the default will allow the server to set them automatically.

SecurityAllocator

Controls the automatic allocation of UIDs and MCS labels to a project. If nil, allocation is disabled.

UIDAllocatorRange

Defines the total set of Unix user IDs (UIDs) that will be allocated to projects automatically, and the size of the block each namespace gets. For example, 1000-1999/10 will allocate ten UIDs per namespace, and will be able to allocate up to 100 blocks before running out of space. The default is to allocate from 1 billion to 2 billion in 10k blocks (which is the expected size of the ranges container images will use once user namespaces are started).

Service Account Configuration

Table 7.14. Service Account Configuration Parameters

Parameter Name
Description

LimitSecretReferences

Controls whether or not to allow a service account to reference any secret in a namespace without explicitly referencing them.

ManagedNames

A list of service account names that will be auto-created in every namespace. If no names are specified, the ServiceAccountsController will not be started.

MasterCA

The CA for verifying the TLS connection back to the master. The service account controller will automatically inject the contents of this file into pods so they can verify connections to the master.

PrivateKeyFile

A file containing a PEM-encoded private RSA key, used to sign service account tokens. If no private key is specified, the service account TokensController will not be started.

PublicKeyFiles

A list of files, each containing a PEM-encoded public RSA key. If any file contains a private key, the public portion of the key is used. The list of public keys is used to verify presented service account tokens. Each key is tried in order until the list is exhausted or verification succeeds. If no keys are specified, no service account authentication will be available.

ServiceAccountConfig

Holds the necessary configuration options for a service account.

Serving Information Configuration

Table 7.15. Serving Information Configuration Parameters

Parameter Name
Description

AllowRecursiveQueries

Allows the DNS server on the master to answer queries recursively. Note that open resolvers can be used for DNS amplification attacks and the master DNS should not be made accessible to public networks.

BindAddress

The ip:port to serve on.

BindNetwork

Controls limits and behavior for importing images.

CertFile

A file containing a PEM-encoded certificate.

CertInfo

TLS cert information for serving secure traffic.

ClientCA

The certificate bundle for all the signers that you recognize for incoming client certificates.

dnsConfig

Holds the necessary configuration options for DNS.

DNSDomain

Holds the domain suffix.

DNSIP

Holds the IP.

KeyFile

A file containing a PEM-encoded private key for the certificate specified by CertFile.

MasterClientConnectionOverrides

Provides overrides to the client connection used to connect to the master.

MaxRequestsInFlight

The number of concurrent requests allowed to the server. If zero, no limit.

NamedCertificates

A list of certificates to use to secure requests to specific host names.

RequestTimeoutSecond

The number of seconds before requests are timed out. The default is 60 minutes. If -1, there is no limit on requests.

ServingInfo

The HTTP serving information for the assets.

Volume Configuration

Table 7.16. Volume Configuration Parameters

Parameter Name
Description

DynamicProvisioningEnabled

A boolean to enable or disable dynamic provisioning. Default is true.

FSGroup

Can be specified to enable a quota on local storage use per unique FSGroup ID. At present this is only implemented for emptyDir volumes, and if the underlying volumeDirectory is on an XFS filesystem.

LocalQuota

Contains options for controlling local volume quota on the node.

MasterVolumeConfig

Contains options for configuring volume plug-ins in the master node.

NodeVolumeConfig

Contains options for configuring volumes on the node.

VolumeConfig

Contains options for configuring volumes on the node.

VolumeDirectory

The directory that volumes are stored under.

Audit Configuration

Audit provides a security-relevant chronological set of records documenting the sequence of activities that have affected system by individual users, administrators, or other components of the system.

Audit works at the API server level, logging all requests coming to the server. Each audit log contains two entries:

The request line containing:

A Unique ID allowing to match the response line (see #2)

The source IP of the request

The HTTP method being invoked

The original user invoking the operation

The impersonated user for the operation

The namespace of the request or <none>

The URI as requested

The response line containing:

The the unique ID from #1

The response code

Example output for user admin asking for a list of pods:

AUDIT: id="5c3b8227-4af9-4322-8a71-542231c3887b" ip="127.0.0.1" method="GET" user="admin" as="<self>" namespace="default" uri="/api/v1/namespaces/default/pods"
AUDIT: id="5c3b8227-4af9-4322-8a71-542231c3887b" response="200"

Table 7.17. Audit Configuration Parameters

Parameter Name
Description

Enabled

A boolean to enable or disable audit logs. Default is false.

Node Configuration Files

The following node-config.yaml file is a sample node configuration file that was generated with the default values as of writing. You can create a new node configuration file to see the valid options for your installed version of OpenShift Container Platform.

Example 7.1. Sample Node Configuration File

allowDisabledDocker: false
apiVersion: v1
authConfig:
  authenticationCacheSize: 1000
  authenticationCacheTTL: 5m
  authorizationCacheSize: 1000
  authorizationCacheTTL: 5m
dnsDomain: cluster.local
dnsIP: 10.0.2.15
dockerConfig:
  execHandlerName: native
imageConfig:
  format: openshift/origin-${component}:${version}
  latest: false
iptablesSyncPeriod: 5s
kind: NodeConfig
masterKubeConfig: node.kubeconfig
networkConfig:
  mtu: 1450
  networkPluginName: ""
nodeIP: ""
nodeName: node1.example.com
podManifestConfig:
  path: "/path/to/pod-manifest-file"
  fileCheckIntervalSeconds: 30
proxyArguments:
  proxy-mode:
  - iptables
volumeConfig:
  localQuota:
   perFSGroup: null
servingInfo:
  bindAddress: 0.0.0.0:10250
  bindNetwork: tcp4
  certFile: server.crt
  clientCA: node-client-ca.crt
  keyFile: server.key
  namedCertificates: null
volumeDirectory: /root/openshift.local.volumes

Configures an IP address to be prepended to a pod’s /etc/resolv.conf by adding the address here.

Allows pods to be placed directly on certain set of nodes, or on all nodes without going through the scheduler. You can then use pods to perform the same administrative tasks and support the same services on each node.

Specifies the path for the pod manifest file or directory. If it is a directory, then it is expected to contain one or more manifest files. This is used by the Kubelet to create pods on the node.

This is the interval (in seconds) for checking the manifest file for new data. The interval must be a positive value.

The service proxy implementation to use.

Preliminary support for local emptyDir volume quotas, set this value to a resource quantity representing the desired quota per FSGroup, per node. (i.e. 1Gi, 512Mi, etc) Currently requires that the volumeDirectory be on an XFS filesystem mounted with the 'gquota' option, and the matching security context contraint’s fsGroup type set to 'MustRunAs'.

Pod and Node Configuration

Table 7.18. Pod and Node Configuration Parameters

Parameter Name
Description

NodeConfig

The fully specified configuration starting an OpenShift Container Platform node.

NodeIP

Node may have multiple IPs, so this specifies the IP to use for pod traffic routing. If not specified, network parse/lookup on the nodeName is performed and the first non-loopback address is used.

NodeName

The value used to identify this particular node in the cluster. If possible, this should be your fully qualified hostname. If you are describing a set of static nodes to the master, this value must match one of the values in the list.

PodEvictionTimeout

Controls grace period for deleting pods on failed nodes. It takes valid time duration string. If empty, you get the default pod eviction timeout.

ProxyClientInfo

Specifies the client cert/key to use when proxying to pods.

Docker Configuration

Table 7.19. Docker Configuration Parameters

Parameter Name
Description

AllowDisabledDocker

If true, the kubelet will ignore errors from Docker. This means that a node can start on a machine that does not have docker started.

DockerConfig

Holds Docker related configuration options

ExecHandlerName

The handler to use for executing commands in Docker containers.

Parallel Image Pulls with Docker 1.9+

If you are using Docker 1.9+, you may want to consider enabling parallel image pulling, as the default is to pull images one at a time.

Note

There is a potential issue with data corruption prior to Docker 1.9. However, starting with 1.9, the corruption issue is resolved and it is safe to switch to parallel pulls.

kubeletArguments:
  serialize-image-pulls:
  - "false"

Change to true to disable parallel pulls. (This is the default config)

Passwords and Other Sensitive Data

For some authentication configurations, an LDAP bindPassword or OAuth clientSecret value is required. Instead of specifying these values directly in the master configuration file, these values may be provided as environment variables, external files, or in encrypted files.

Environment Variable Example

  ...
  bindPassword:
    env: BIND_PASSWORD_ENV_VAR_NAME

External File Example

  ...
  bindPassword:
    file: bindPassword.txt

Encrypted External File Example

  ...
  bindPassword:
    file: bindPassword.encrypted
    keyFile: bindPassword.key

To create the encrypted file and key file for the above example:

$ oadm ca encrypt --genkey=bindPassword.key --out=bindPassword.encrypted
> Data to encrypt: B1ndPass0rd!

Warning

Encrypted data is only as secure as the decrypting key. Care should be taken to limit filesystem permissions and access to the key file.

Creating New Configuration Files

When defining an OpenShift Container Platform configuration from scratch, start by creating new configuration files.

For master host configuration files, use the openshift start command with the --write-config option to write the configuration files. For node hosts, use the oadm create-node-config command to write the configuration files.

The following commands write the relevant launch configuration file(s), certificate files, and any other necessary files to the specified --write-config or --node-dir directory.

To create configuration files for an all-in-one server (a master and a node on the same host) in the specified directory:

$ openshift start --write-config=/openshift.local.config

To create a master configuration file and other required files in the specified directory:

$ openshift start master --write-config=/openshift.local.config/master

To create a node configuration file and other related files in the specified directory:

$ oadm create-node-config \
    --node-dir=/openshift.local.config/node-<node_hostname> \
    --node=<node_hostname> \
    --hostnames=<node_hostname>,<ip_address> \
    --certificate-authority="/path/to/ca.crt" \
    --signer-cert="/path/to/ca.crt" \
    --signer-key="/path/to/ca.key"
    --signer-serial="/path/to/ca.serial.txt"
    --node-client-certificate-authority="/path/to/ca.crt"

When creating node configuration files, the --hostnames option accepts a comma-delimited list of every host name or IP address you want server certificates to be valid for.

Launching Servers Using Configuration Files

Once you have modified the master and/or node configuration files to your specifications, you can use them when launching servers by specifying them as an argument. Keep in mind that if you specify a configuration file, none of the other command line options you pass are respected.

To launch an all-in-one server using a master configuration and a node configuration file:

$ openshift start --master-config=/openshift.local.config/master/master-config.yaml --node-config=/openshift.local.config/node-<node_hostname>/node-config.yaml

To launch a master server using a master configuration file:

$ openshift start master --config=/openshift.local.config/master/master-config.yaml

To launch a node server using a node configuration file:

$ openshift start node --config=/openshift.local.config/node-<node_hostname>/node-config.yaml

Chapter 8. Adding Hosts to an Existing Cluster

Overview

Depending on how your OpenShift Container Platform cluster was installed, you can add new hosts (either nodes or masters) to your installation by using the install tool for quick installations, or by using the scaleup.yml playbook for advanced installations.

Adding Hosts Using the Quick Installer Tool

If you used the quick install tool to install your OpenShift Container Platform cluster, you can use the quick install tool to add a new node host to your existing cluster, or to reinstall the cluster entirely.

Note

Currently, you can not use the quick installer tool to add new master hosts. You must use the advanced installation method to do so.

If you used the installer in either interactive or unattended mode, you can re-run the installation as long as you have an installation configuration file at ~/.config/openshift/installer.cfg.yml (or specify a different location with the -c option).

Important

The recommended maximum number of nodes is 300.

To add nodes to your installation:

Re-run the installer with the install subcommand in interactive or unattended mode:

$ atomic-openshift-installer [-u] [-c </path/to/file>] install

The installer detects your current environment and allows you to either add an additional node or re-perform a clean install:

Gathering information from hosts...
Installed environment detected.
By default the installer only adds new nodes to an installed environment.
Do you want to (1) only add additional nodes or (2) perform a clean install?:

Choose (1) and follow the on-screen instructions to complete your desired task.

Adding Hosts Using the Advanced Install

If you installed using the advanced install, you can add new hosts to your cluster by running the scaleup.yml playbook. This playbook queries the master, generates and distributes new certificates for the new hosts, then runs the configuration playbooks on the new hosts only. Before running the scaleup.yml playbook, complete all prerequisite host preparation steps.

This process is similar to re-running the installer in the quick installation method to add nodes, however you have more configuration options available when using the advanced method and when running the playbooks directly.

You must have an existing inventory file (for example, /etc/ansible/hosts) that is representative of your current cluster configuration in order to run the scaleup.yml playbook. If you previously used the atomic-openshift-installer command to run your installation, you can check ~/.config/openshift/hosts (previously located at ~/.config/openshift/.ansible/hosts) for the last inventory file that the installer generated, and use or modify that as needed as your inventory file. You must then specify the file location with -i when calling ansible-playbook later.

Important

The recommended maximum number of nodes is 300.

To add a host to an existing cluster:

Ensure you have the latest playbooks by updating the atomic-openshift-utils package:

# yum update atomic-openshift-utils

Edit your /etc/ansible/hosts file and add new_<host_type> to the [OSEv3:children] section:

For example, to add a new node host, add new_nodes:

[OSEv3:children]
masters
nodes
new_nodes

To add new master hosts, add new_masters.

Create a [new_<host_type>] section much like an existing section, specifying host information for any new hosts you want to add. For example, when adding a new node:

[nodes]
master[1:3].example.com openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"
node2.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

[new_nodes]
node3.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

See Configuring Host Variables for more options.

When adding new masters, hosts added to the [new_masters] section must also be added to the [new_nodes] section with the openshift_schedulable=false variable. This ensures the new master host is part of the OpenShift SDN and that pods are not scheduled for placement on them. For example:

[masters]
master[1:2].example.com

[new_masters]
master3.example.com

[nodes]
node[1:3].example.com openshift_node_labels="{'region': 'infra'}"
master[1:2].example.com openshift_schedulable=false

[new_nodes]
master3.example.com openshift_schedulable=false

Run the scaleup.yml playbook. If your inventory file is located somewhere other than the default of /etc/ansible/hosts, specify the location with the -i option.

For additional nodes:

# ansible-playbook [-i /path/to/file] \
    /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-node/scaleup.yml

For additional masters:

# ansible-playbook [-i /path/to/file] \
    usr/share/ansible/openshift-ansible/playbooks/byo/openshift-master/scaleup.yml

After the playbook completes successfully, verify the installation.

Finally, move any hosts you had defined in the [new_<host_type>] section into their appropriate section (but leave the [new_<host_type>] section definition itself in place) so that subsequent runs using this inventory file are aware of the nodes but do not handle them as new nodes. For example, when adding new nodes:

[nodes]
master[1:3].example.com openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node1.example.com openshift_node_labels="{'region': 'primary', 'zone': 'east'}"
node2.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"
node3.example.com openshift_node_labels="{'region': 'primary', 'zone': 'west'}"

[new_nodes]

Chapter 9. Loading the Default Image Streams and Templates

Overview

Your OpenShift Container Platform installation includes useful sets of Red Hat-provided image streams and templates to make it easy for developers to create new applications. By default, the quick and advanced installation methods automatically create these sets in the openshift project, which is a default global project to which all users have view access.

Offerings by Subscription Type

Depending on the active subscriptions on your Red Hat account, the following sets of image streams and templates are provided and supported by Red Hat. Contact your Red Hat sales representative for further subscription details.

OpenShift Container Platform Subscription

The core set of image streams and templates are provided and supported with an active OpenShift Container Platform subscription. This includes the following technologies:

Type
Technology

Languages & Frameworks

.NET Core

Node.js

Perl

PHP

Python

Ruby

Databases

MongoDB

MySQL

PostgreSQL

Middleware Services

Red Hat JBoss Web Server (Tomcat)

Red Hat Single Sign-on

Other Services

Jenkins

xPaaS Middleware Add-on Subscriptions

Support for xPaaS middleware images are provided by xPaaS Middleware add-on subscriptions, which are separate subscriptions for each xPaaS product. If the relevant subscription is active on your account, image streams and templates are provided and supported for the following technologies:

Type
Technology

Middleware Services

Red Hat JBoss A-MQ

Red Hat JBoss BPM Suite Intelligent Process Server

Red Hat JBoss BRMS Decision Server

Red Hat JBoss Data Grid

Red Hat JBoss EAP

Red Hat JBoss Fuse Integration Services

Before You Begin

Before you consider performing the tasks in this topic, confirm if these image streams and templates are already registered in your OpenShift Container Platform cluster by doing one of the following:

Log into the web console and click Add to Project.

List them for the openshift project using the CLI:

$ oc get is -n openshift
$ oc get templates -n openshift

If the default image streams and templates are ever removed or changed, you can follow this topic to create the default objects yourself. Otherwise, the following instructions are not necessary.

Prerequisites

Before you can create the default image streams and templates:

The integrated Docker registry service must be deployed in your OpenShift Container Platform installation.

You must be able to run the oc create command with cluster-admin privileges, because they operate on the default openshiftproject.

You must have installed the atomic-openshift-utils RPM package. See Software Prerequisites for instructions.

Define shell variables for the directories containing image streams and templates. This significantly shortens the commands in the following sections. To do this:

$ IMAGESTREAMDIR="/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.1/image-streams"; \
    XPAASSTREAMDIR="/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.1/xpaas-streams"; \
    XPAASTEMPLATES="/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.1/xpaas-templates"; \
    DBTEMPLATES="/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.1/db-templates"; \
    QSTEMPLATES="/usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.1/quickstart-templates"

Creating Image Streams for OpenShift Container Platform Images

If your node hosts are subscribed using Red Hat Subscription Manager and you want to use the core set of image streams that used Red Hat Enterprise Linux (RHEL) 7 based images:

$ oc create -f $IMAGESTREAMDIR/image-streams-rhel7.json -n openshift

Alternatively, to create the core set of image streams that use the CentOS 7 based images:

$ oc create -f $IMAGESTREAMDIR/image-streams-centos7.json -n openshift

Creating both the CentOS and RHEL sets of image streams is not possible, because they use the same names. To have both sets of image streams available to users, either create one set in a different project, or edit one of the files and modify the image stream names to make them unique.

Creating Image Streams for xPaaS Middleware Images

The xPaaS Middleware image streams provide images for JBoss EAP, JBoss JWS, JBoss A-MQ, JBoss Fuse Integration Services, Decision Server, and JBoss Data Grid. They can be used to build applications for those platforms using the provided templates.

To create the xPaaS Middleware set of image streams:

$ oc create -f $XPAASSTREAMDIR/jboss-image-streams.json -n openshift

Note

Access to the images referenced by these image streams requires the relevant xPaaS Middleware subscriptions.

Creating Database Service Templates

The database service templates make it easy to run a database image which can be utilized by other components. For each database (MongoDB, MySQL, and PostgreSQL), two templates are defined.

One template uses ephemeral storage in the container which means data stored will be lost if the container is restarted, for example if the pod moves. This template should be used for demonstration purposes only.

The other template defines a persistent volume for storage, however it requires your OpenShift Container Platform installation to have persistent volumes configured.

To create the core set of database templates:

$ oc create -f $DBTEMPLATES -n openshift

After creating the templates, users are able to easily instantiate the various templates, giving them quick access to a database deployment.

Creating Instant App and Quickstart Templates

The Instant App and Quickstart templates define a full set of objects for a running application. These include:

Build configurations to build the application from source located in a GitHub public repository

Deployment configurations to deploy the application image after it is built.

Services to provide load balancing for the application pods.

Routes to provide external access to the application.

Some of the templates also define a database deployment and service so the application can perform database operations.

Note

The templates which define a database use ephemeral storage for the database content. These templates should be used for demonstration purposes only as all database data will be lost if the database pod restarts for any reason.

Using these templates, users are able to easily instantiate full applications using the various language images provided with OpenShift Container Platform. They can also customize the template parameters during instantiation so that it builds source from their own repository rather than the sample repository, so this provides a simple starting point for building new applications.

To create the core Instant App and Quickstart templates:

$ oc create -f $QSTEMPLATES -n openshift

There is also a set of templates for creating applications using various xPaaS Middleware products (JBoss EAP, JBoss JWS, JBoss A-MQ, JBoss Fuse Integration Services, Decision Server, and JBoss Data Grid), which can be registered by running:

$ oc create -f $XPAASTEMPLATES -n openshift

Note

The xPaaS Middleware templates require the xPaaS Middleware image streams, which in turn require the relevant xPaaS Middleware subscriptions.

Note

The templates which define a database use ephemeral storage for the database content. These templates should be used for demonstration purposes only as all database data will be lost if the database pod restarts for any reason.

What’s Next?

With these artifacts created, developers can now log into the web console and follow the flow for creating from a template. Any of the database or application templates can be selected to create a running database service or application in the current project. Note that some of the application templates define their own database services as well.

The example applications are all built out of GitHub repositories which are referenced in the templates by default, as seen in the SOURCE_REPOSITORY_URL parameter value. Those repositories can be forked, and the fork can be provided as the SOURCE_REPOSITORY_URL parameter value when creating from the templates. This allows developers to experiment with creating their own applications.

You can direct your developers to the Using the Instant App and Quickstart Templates section in the Developer Guide for these instructions.

Chapter 10. Configuring Custom Certificates

Overview

Administrators can configure custom serving certificates for the public host names of the OpenShift Container Platform API and web console. This can be done during an advanced installation or configured after installation.

Configuring Custom Certificates with Ansible

During advanced installations, custom certificates can be configured using the openshift_master_named_certificates and openshift_master_overwrite_named_certificates parameters, which are configurable in the inventory file. More details are available about configuring custom certificates with Ansible.

Example 10.1. Example Custom Certificate Configuration with Ansible

# Configure custom named certificates
# NOTE: openshift_master_named_certificates is cached on masters and is an
# additive fact, meaning that each run with a different set of certificates
# will add the newly provided certificates to the cached set of certificates.
#
# An optional CA may be specified for each named certificate. CAs will
# be added to the OpenShift CA bundle which allows for the named
# certificate to be served for internal cluster communication.
#
# If you would like openshift_master_named_certificates to be overwritten with
# the provided value, specify openshift_master_overwrite_named_certificates.
openshift_master_overwrite_named_certificates=true
#
# Provide local certificate paths which will be deployed to masters
openshift_master_named_certificates=[{"certfile": "/path/on/host/to/custom1.crt", "keyfile": "/path/on/host/to/custom1.key", "cafile": "/path/on/host/to/custom-ca1.crt"}]
#
# Detected names may be overridden by specifying the "names" key
#openshift_master_named_certificates=[{"certfile": "/path/on/host/to/custom1.crt", "keyfile": "/path/on/host/to/custom1.key", "names": ["public-master-host.com"], "cafile": "/path/on/host/to/custom-ca1.crt"}]

Configuring Custom Certificates

In the master configuration file you can list the namedCertificates section in the assetConfig.servingInfo section so the custom certificate serves up for the web console, and in the servingInfo section so the custom certificate serves up for the CLI and other API calls. Multiple certificates can be configured this way and each certificate may be associated with multiple host names or wildcards.

A default certificate must be configured in the servingInfo.certFile and servingInfo.keyFile configuration sections in addition to namedCertificates.

Note

The namedCertificates section should only be configured for the host name associated with the masterPublicURL, assetConfig.publicURL, and oauthConfig.assetPublicURL settings. Using a custom serving certificate for the host name associated with the masterURL will result in TLS errors as infrastructure components will attempt to contact the master API using the internal masterURL host.

Example 10.2. Custom Certificates Configuration

servingInfo:
  ...
  namedCertificates:
  - certFile: custom.crt
    keyFile: custom.key
    names:
    - "customhost.com"
    - "api.customhost.com"
    - "console.customhost.com"
  - certFile: wildcard.crt
    keyFile: wildcard.key
    names:
    - "*.wildcardhost.com"
  ...

Relative paths are resolved relative to the master configuration file. Restart the server to pick up the configuration changes.

Chapter 11. Redeploying Certificates

Overview

This topic reviews how to back up and redeploy cluster certificates using the ansible-playbook command. This method fixes common certificate errors. Possible use cases include:

The installer detected the wrong host names and the issue was identified too late.

The certificates are expired and you need to update them.

You have a new CA and would like to create certificates using it instead

Running the Certificate Redeploy Playbook

Running the certificate redeploy playbook will redeploy OpenShift Container Platform certificates that exist on systems (master, node, etcd):

$ ansible-playbook -i <inventory> playbooks/byo/openshift-cluster/redeploy-certificates.yml

Warning

This playbook must be run with an inventory that is representative of the cluster. The inventory must specify or override all host names and IP addresses set via openshift_hostname, openshift_public_hostname, openshift_ip, openshift_public_ip, openshift_master_cluster_hostname, or openshift_master_cluster_public_hostname such that they match the current cluster configuration.

By default, the redeploy playbook does not redeploy the OpenShift Container Platform CA. New certificates are created using the original OpenShift Container Platform CA.

To redeploy all certificates including the OpenShift Container Platform CA, specify openshift_certificates_redeploy_ca=true.

For example:

$ ansible-playbook -i <inventory> playbooks/byo/openshift-cluster/redeploy-certificates.yml \
--extra-vars "openshift_certificates_redeploy_ca=true"

This also adds a custom CA certificate:

# Configure custom ca certificate
# NOTE: CA certificate will not be replaced with existing clusters.
# This option may only be specified when creating a new cluster or
# when redeploying cluster certificates with the redeploy-certificates
# playbook.
#openshift_master_ca_certificate={'certfile': '/path/to/ca.crt', 'keyfile': '/path/to/ca.key'}

All pods using service accounts to communicate with the OpenShift Container Platform API must be redeployed when the OpenShift Container Platform CA is replaced so the certificate redeploy playbook will serially evacuate all nodes in the cluster when this variable is set.

Chapter 12. Configuring Authentication and User Agent

Overview

The OpenShift Container Platform master includes a built-in OAuth server. Developers and administrators obtain OAuth access tokens to authenticate themselves to the API.

As an administrator, you can configure OAuth using the master configuration file to specify an identity provider. This can be done during an advanced installation or configured after installation.

If you installed OpenShift Container Platform using the Quick Installation or Advanced Installation method, the Deny All identity provider is used by default, which denies access for all user names and passwords. To allow access, you must choose a different identity provider and configure the master configuration file appropriately (located at /etc/origin/master/master-config.yaml by default).

When running a master without a configuration file, the Allow All identity provider is used by default, which allows any non-empty user name and password to log in. This is useful for testing purposes. To use other identity providers, or to modify any token, grant, or session options, you must run the master from a configuration file.

Note

Roles need to be assigned to administer the setup with an external user.

Configuring Identity Providers with Ansible

For initial advanced installations, the Deny All identity provider is configured by default, though it can be overridden during installation using the openshift_master_identity_providers parameter, which is configurable in the inventory file. Session options in the OAuth configuration are also configurable in the inventory file.

Example 12.1. Example Identity Provider Configuration with Ansible

# htpasswd auth
openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/htpasswd'}]
# Defining htpasswd users
#openshift_master_htpasswd_users={'user1': '<pre-hashed password>', 'user2': '<pre-hashed password>'
# or
#openshift_master_htpasswd_file=<path to local pre-generated htpasswd file>

# Allow all auth
#openshift_master_identity_providers=[{'name': 'allow_all', 'login': 'true', 'challenge': 'true', 'kind': 'AllowAllPasswordIdentityProvider'}]

# LDAP auth
#openshift_master_identity_providers=[{'name': 'my_ldap_provider', 'challenge': 'true', 'login': 'true', 'kind': 'LDAPPasswordIdentityProvider', 'attributes': {'id': ['dn'], 'email': ['mail'], 'name': ['cn'], 'preferredUsername': ['uid']}, 'bindDN': '', 'bindPassword': '', 'ca': '', 'insecure': 'false', 'url': 'ldap://ldap.example.com:389/ou=users,dc=example,dc=com?uid'}]
# Configuring the ldap ca certificate
#openshift_master_ldap_ca=<ca text>
# or
#openshift_master_ldap_ca_file=<path to local ca file to use>

# Available variables for configuring certificates for other identity providers:
#openshift_master_openid_ca
#openshift_master_openid_ca_file
#openshift_master_request_header_ca
#openshift_master_request_header_ca_file

Identity Providers

You can configure the master host for authentication using your desired identity provider by modifying the master configuration file. The following sections detail the identity providers supported by OpenShift Container Platform.

There are four parameters common to all identity providers:

Parameter
Description

name

The provider name is prefixed to provider user names to form an identity name.

challenge

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header. Not supported by all identity providers.

To prevent cross-site request forgery (CSRF) attacks against browser clients Basic authentication challenges are only sent if a X-CSRF-Token header is present on the request. Clients that expect to receive Basic WWW-Authenticate challenges should set this header to a non-empty value.

login

When true, unauthenticated token requests from web clients (like the web console) are redirected to a login page backed by this provider. Not supported by all identity providers.

If you want users to be sent to a branded page before being redirected to the identity provider’s login, then set oauthConfig → alwaysShowProviderSelection: true in the master configuration file. This provider selection page can be customized.

mappingMethod

Defines how new identities are mapped to users when they login. See Mapping Identities to Users for more information.

Note

When adding or changing identity providers, you can map identities from the new provider to existing users by setting the mappingMethod parameter to add.

Mapping Identities to Users

Setting the mappingMethod parameter in a master configuration file determines how identities are mapped to users:

...
oauthConfig:
  identityProviders:
  - name: htpasswd_auth
    challenge: true
    login: false
    mappingMethod: "claim"
...

When set to the default claim value, OAuth will fail if the identity is mapped to a previously-existing user name. The following table outlines the use cases for the available mappingMethod parameter values:

Parameter
Description

claim

The default value. Provisions a user with the identity’s preferred user name. Fails if a user with that user name is already mapped to another identity.

lookup

Looks up an existing identity, user identity mapping, and user, but does not automatically provision users or identities. This allows cluster administrators to set up identities and users manually, or using an external process.

generate

Provisions a user with the identity’s preferred user name. If a user with the preferred user name is already mapped to an existing identity, a unique user name is generated. For example, myuser2. This method should not be used in combination with external processes that require exact matches between OpenShift Container Platform user names and identity provider user names, such as LDAP group sync.

add

Provisions a user with the identity’s preferred user name. If a user with that user name already exists, the identity is mapped to the existing user, adding to any existing identity mappings for the user. Required when multiple identity providers are configured that identify the same set of users and map to the same user names.

Allow All

Set AllowAllPasswordIdentityProvider in the identityProviders stanza to allow any non-empty user name and password to log in. This is the default identity provider when running OpenShift Container Platform without a master configuration file.

Example 12.2. Master Configuration Using AllowAllPasswordIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_allow_provider
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: AllowAllPasswordIdentityProvider

This provider name is prefixed to provider user names to form an identity name.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider.

When true, unauthenticated token requests from web clients (like the web console) are redirected to a login page backed by this provider.

Controls how mappings are established between this provider’s identities and user objects, as described above.

Deny All

Set DenyAllPasswordIdentityProvider in the identityProviders stanza to deny access for all user names and passwords.

Example 12.3. Master Configuration Using DenyAllPasswordIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_deny_provider
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: DenyAllPasswordIdentityProvider

This provider name is prefixed to provider user names to form an identity name.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider.

When true, unauthenticated token requests from web clients (like the web console) are redirected to a login page backed by this provider.

Controls how mappings are established between this provider’s identities and user objects, as described above.

HTPasswd

Set HTPasswdPasswordIdentityProvider in the identityProviders stanza to validate user names and passwords against a flat file generated using htpasswd.

Note

The htpasswd utility is in the httpd-tools package:

# yum install httpd-tools

OpenShift Container Platform supports the Bcrypt, SHA-1, and MD5 cryptographic hash functions, and MD5 is the default for htpasswd. Plaintext, encrypted text, and other hash functions are not currently supported.

The flat file is reread if its modification time changes, without requiring a server restart.

To create the file, run:

$ htpasswd -c </path/to/users.htpasswd> <user_name>

To add or update a login to the file, run:

$ htpasswd </path/to/users.htpasswd> <user_name>

To remove a login from the file, run:

$ htpasswd -D </path/to/users.htpasswd> <user_name>

Example 12.4. Master Configuration Using HTPasswdPasswordIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_htpasswd_provider
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: HTPasswdPasswordIdentityProvider
      file: /path/to/users.htpasswd

This provider name is prefixed to provider user names to form an identity name.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider.

When true, unauthenticated token requests from web clients (like the web console) are redirected to a login page backed by this provider.

Controls how mappings are established between this provider’s identities and user objects, as described above.

File generated using htpasswd.

Keystone

Set KeystonePasswordIdentityProvider in the identityProviders stanza to validate user names and passwords against an OpenStack Keystone v3 server. This enables shared authentication with an OpenStack server configured to store users in an internal Keystone database.

Example 12.5. Master Configuration Using KeystonePasswordIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_keystone_provider
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: KeystonePasswordIdentityProvider
      domainName: default
      url: http://keystone.example.com:5000
      ca: ca.pem
      certFile: keystone.pem
      keyFile: keystonekey.pem

This provider name is prefixed to provider user names to form an identity name.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider.

When true, unauthenticated token requests from web clients (like the web console) are redirected to a login page backed by this provider.

Controls how mappings are established between this provider’s identities and user objects, as described above.

Keystone domain name. In Keystone, usernames are domain-specific. Only a single domain is supported.

The URL to use to connect to the Keystone server (required).

Optional: Certificate bundle to use to validate server certificates for the configured URL.

Optional: Client certificate to present when making requests to the configured URL.

Key for the client certificate. Required if certFile is specified.

LDAP Authentication

Set LDAPPasswordIdentityProvider in the identityProviders stanza to validate user names and passwords against an LDAPv3 server, using simple bind authentication.

During authentication, the LDAP directory is searched for an entry that matches the provided user name. If a single unique match is found, a simple bind is attempted using the distinguished name (DN) of the entry plus the provided password.

These are the steps taken:

Generate a search filter by combining the attribute and filter in the configured url with the user-provided user name.

Search the directory using the generated filter. If the search does not return exactly one entry, deny access.

Attempt to bind to the LDAP server using the DN of the entry retrieved from the search, and the user-provided password.

If the bind is unsuccessful, deny access.

If the bind is successful, build an identity using the configured attributes as the identity, email address, display name, and preferred user name.

The configured url is an RFC 2255 URL, which specifies the LDAP host and search parameters to use. The syntax of the URL is:

ldap://host:port/basedn?attribute?scope?filter

For the above example:

URL Component
Description

ldap

For regular LDAP, use the string ldap. For secure LDAP (LDAPS), use ldaps instead.

host:port

The name and port of the LDAP server. Defaults to localhost:389 for ldap and localhost:636 for LDAPS.

basedn

The DN of the branch of the directory where all searches should start from. At the very least, this must be the top of your directory tree, but it could also specify a subtree in the directory.

attribute

The attribute to search for. Although RFC 2255 allows a comma-separated list of attributes, only the first attribute will be used, no matter how many are provided. If no attributes are provided, the default is to use uid. It is recommended to choose an attribute that will be unique across all entries in the subtree you will be using.

scope

The scope of the search. Can be either either one or sub. If the scope is not provided, the default is to use a scope of sub.

filter

A valid LDAP search filter. If not provided, defaults to (objectClass=*)

When doing searches, the attribute, filter, and provided user name are combined to create a search filter that looks like:

(&(<filter>)(<attribute>=<username>))

For example, consider a URL of:

ldap://ldap.example.com/o=Acme?cn?sub?(enabled=true)

When a client attempts to connect using a user name of bob, the resulting search filter will be (&(enabled=true)(cn=bob)).

If the LDAP directory requires authentication to search, specify a bindDN and bindPassword to use to perform the entry search.

Example 12.6. Master Configuration Using LDAPPasswordIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: "my_ldap_provider"
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: LDAPPasswordIdentityProvider
      attributes:
        id:
        - dn
        email:
        - mail
        name:
        - cn
        preferredUsername:
        - uid
      bindDN: ""
      bindPassword: ""
      ca: my-ldap-ca-bundle.crt
      insecure: false
      url: "ldap://ldap.example.com/ou=users,dc=acme,dc=com?uid"

This provider name is prefixed to the returned user ID to form an identity name.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider.

When true, unauthenticated token requests from web clients (like the web console) are redirected to a login page backed by this provider.

Controls how mappings are established between this provider’s identities and user objects, as described above.

List of attributes to use as the identity. First non-empty attribute is used. At least one attribute is required. If none of the listed attribute have a value, authentication fails.

List of attributes to use as the email address. First non-empty attribute is used.

List of attributes to use as the display name. First non-empty attribute is used.

List of attributes to use as the preferred user name when provisioning a user for this identity. First non-empty attribute is used.

Optional DN to use to bind during the search phase.

Optional password to use to bind during the search phase. This value may also be provided in an environment variable, external file, or encrypted file.

Certificate bundle to use to validate server certificates for the configured URL. If empty, system trusted roots are used. Only applies if insecure: false.

When true, no TLS connection is made to the server. When false, ldaps:// URLs connect using TLS, and ldap:// URLs are upgraded to TLS.

An RFC 2255 URL which specifies the LDAP host and search parameters to use, as described above.

Basic Authentication (Remote)

Set BasicAuthPasswordIdentityProvider in the identityProviders stanza to validate user names and passwords against a remote server using a server-to-server Basic authentication request. User names and passwords are validated against a remote URL that is protected by Basic authentication and returns JSON.

A 401 response indicates failed authentication.

A non-200 status, or the presence of a non-empty "error" key, indicates an error:

{"error":"Error message"}

A 200 status with a sub (subject) key indicates success:

{"sub":"userid"}

The subject must be unique to the authenticated user and must not be able to be modified.

A successful response may optionally provide additional data, such as:

A display name using the name key. For example:

{"sub":"userid", "name": "User Name", ...}

An email address using the email key. For example:

{"sub":"userid", "email":"user@example.com", ...}

A preferred user name using the preferred_username key. This is useful when the unique, unchangeable subject is a database key or UID, and a more human-readable name exists. This is used as a hint when provisioning the OpenShift Container Platform user for the authenticated identity. For example:

{"sub":"014fbff9a07c", "preferred_username":"bob", ...}

Example 12.7. Master Configuration Using BasicAuthPasswordIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_remote_basic_auth_provider
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: BasicAuthPasswordIdentityProvider
      url: https://www.example.com/remote-idp
      ca: /path/to/ca.file
      certFile: /path/to/client.crt
      keyFile: /path/to/client.key

This provider name is prefixed to the returned user ID to form an identity name.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider.

When true, unauthenticated token requests from web clients (like the web console) are redirected to a login page backed by this provider.

Controls how mappings are established between this provider’s identities and user objects, as described above.

URL accepting credentials in Basic authentication headers.

Optional: Certificate bundle to use to validate server certificates for the configured URL.

Optional: Client certificate to present when making requests to the configured URL.

Key for the client certificate. Required if certFile is specified.

Request Header

Set RequestHeaderIdentityProvider in the identityProviders stanza to identify users from request header values, such as X-Remote-User. It is typically used in combination with an authenticating proxy, which sets the request header value. This is similar to how the remote user plug-in in OpenShift Enterprise 2 allowed administrators to provide Kerberos, LDAP, and many other forms of enterprise authentication.

For users to authenticate using this identity provider, they must access https://<master>/oauth/authorize via an authenticating proxy. You can either proxy the entire master API server so that all access goes through the proxy, or you can configure the OAuth server to redirect unauthenticated requests to the proxy.

To redirect unauthenticated requests from clients expecting login flows:

Set the login parameter to true.

Set the provider.loginURL parameter to the proxy URL to send those clients to.

To redirect unauthenticated requests from clients expecting WWW-Authenticate challenges:

Set the challenge parameter to true.

Set the provider.challengeURL parameter to the proxy URL to send those clients to.

The provider.challengeURL and provider.loginURL parameters can include the following tokens in the query portion of the URL:

${url} is replaced with the current URL, escaped to be safe in a query parameter.

For example: https://www.example.com/sso-login?then=${url}

${query} is replaced with the current query string, unescaped.

For example: https://www.example.com/auth-proxy/oauth/authorize?${query}

Warning

If you expect unauthenticated requests to reach the OAuth server, a clientCA parameter should be set for this identity provider, so that incoming requests are checked for a valid client certificate before the request’s headers are checked for a user name. Otherwise, any direct request to the OAuth server can impersonate any identity from this provider, merely by setting a request header.

Example 12.8. Master Configuration Using RequestHeaderIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_request_header_provider
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: RequestHeaderIdentityProvider
      challengeURL: "https://www.example.com/challenging-proxy/oauth/authorize?${query}"
      loginURL: "https://www.example.com/login-proxy/oauth/authorize?${query}"
      clientCA: /path/to/client-ca.file
      clientCommonNames:
      - my-auth-proxy
      headers:
      - X-Remote-User
      - SSO-User
      emailHeaders:
      - X-Remote-User-Email
      nameHeaders:
      - X-Remote-User-Display-Name
      preferredUsernameHeaders:
      - X-Remote-User-Login

This provider name is prefixed to the user name in the request header to form an identity name.

RequestHeaderIdentityProvider can only respond to clients that request WWW-Authenticate challenges by redirecting to a configured challengeURL. The configured URL should respond with a WWW-Authenticate challenge.

RequestHeaderIdentityProvider can only respond to clients requesting a login flow by redirecting to a configured loginURL. The configured URL should respond with a login flow.

Controls how mappings are established between this provider’s identities and user objects, as described above.

Optional: URL to redirect unauthenticated /oauth/authorize requests to, for clients which expect interactive logins. ${url} is replaced with the current URL, escaped to be safe in a query parameter. ${query} is replaced with the current query string.

Optional: URL to redirect unauthenticated /oauth/authorize requests to, for clients which expect WWW-Authenticate challenges. ${url} is replaced with the current URL, escaped to be safe in a query parameter. ${query} is replaced with the current query string.

Optional: PEM-encoded certificate bundle. If set, a valid client certificate must be presented and validated against the certificate authorities in the specified file before the request headers are checked for user names.

Optional: list of common names (cn). If set, a valid client certificate with a Common Name (cn) in the specified list must be presented before the request headers are checked for user names. If empty, any Common Name is allowed. Can only be used in combination with clientCA.

Header names to check, in order, for the user identity. The first header containing a value is used as the identity. Required, case-insensitive.

Header names to check, in order, for an email address. The first header containing a value is used as the email address. Optional, case-insensitive.

Header names to check, in order, for a display name. The first header containing a value is used as the display name. Optional, case-insensitive.

Header names to check, in order, for a preferred user name, if different than the immutable identity determined from the headers specified in headers. The first header containing a value is used as the preferred user name when provisioning. Optional, case-insensitive.

Example 12.9. Apache Authentication Using RequestHeaderIdentityProvider

This example configures an authentication proxy on the same host as the master. Having the proxy and master on the same host is merely a convenience and may not be suitable for your environment. For example, if you were already running a router on the master, port 443 would not be available.

It is also important to note that while this reference configuration uses Apache’s mod_auth_form, it is by no means required and other proxies can easily be used if the following requirements are met:

Block the X-Remote-User header from client requests to prevent spoofing.

Enforce client certificate authentication in the RequestHeaderIdentityProvider configuration.

Require the X-Csrf-Token header be set for all authentication request using the challenge flow.

Only the /oauth/authorize endpoint should be proxied, and redirects should not be rewritten to allow the backend server to send the client to the correct location.

Installing the Prerequisites

The mod_auth_form module is shipped as part of the mod_session package that is found in the Optional channel:

# yum install -y httpd mod_ssl mod_session apr-util-openssl

Generate a CA for validating requests that submit the trusted header. This CA should be used as the file name for clientCA in the master’s identity provider configuration.

# oadm ca create-signer-cert \
  --cert='/etc/origin/master/proxyca.crt' \
  --key='/etc/origin/master/proxyca.key' \
  --name='openshift-proxy-signer@1432232228' \
  --serial='/etc/origin/master/proxyca.serial.txt'

Generate a client certificate for the proxy. This can be done using any x509 certificate tooling. For convenience, the oadm CLI can be used:

# oadm create-api-client-config \
  --certificate-authority='/etc/origin/master/proxyca.crt' \
  --client-dir='/etc/origin/master/proxy' \
  --signer-cert='/etc/origin/master/proxyca.crt' \
  --signer-key='/etc/origin/master/proxyca.key' \
  --signer-serial='/etc/origin/master/proxyca.serial.txt' \
  --user='system:proxy'

# pushd /etc/origin/master
# cp master.server.crt /etc/pki/tls/certs/localhost.crt
# cp master.server.key /etc/pki/tls/private/localhost.key
# cp ca.crt /etc/pki/CA/certs/ca.crt
# cat proxy/system\:proxy.crt \
  proxy/system\:proxy.key > \
  /etc/pki/tls/certs/authproxy.pem
# popd

The user name can be anything, however it is useful to give it a descriptive name as it will appear in logs.

When running the authentication proxy on a different host name than the master, it is important to generate a certificate that matches the host name instead of using the default master certificate as shown above. The value for masterPublicURL in the /etc/origin/master/master-config.yaml file must be included in the X509v3 Subject Alternative Name in the certificate that is specified for SSLCertificateFile. If a new certificate needs to be created, the oadm ca create-server-cert command can be used.

Configuring Apache

Unlike OpenShift Enterprise 2, this proxy does not need to reside on the same host as the master. It uses a client certificate to connect to the master, which is configured to trust the X-Remote-User header.

Configure Apache per the following:

LoadModule auth_form_module modules/mod_auth_form.so
LoadModule session_module modules/mod_session.so
LoadModule request_module modules/mod_request.so

# Nothing needs to be served over HTTP.  This virtual host simply redirects to
# HTTPS.
<VirtualHost *:80>
  DocumentRoot /var/www/html
  RewriteEngine              On
  RewriteRule     ^(.*)$     https://%{HTTP_HOST}$1 [R,L]
</VirtualHost>

<VirtualHost *:443>
  # This needs to match the certificates you generated.  See the CN and X509v3
  # Subject Alternative Name in the output of:
  # openssl x509 -text -in /etc/pki/tls/certs/localhost.crt
  ServerName www.example.com

  DocumentRoot /var/www/html
  SSLEngine on
  SSLCertificateFile /etc/pki/tls/certs/localhost.crt
  SSLCertificateKeyFile /etc/pki/tls/private/localhost.key
  SSLCACertificateFile /etc/pki/CA/certs/ca.crt

  SSLProxyEngine on
  SSLProxyCACertificateFile /etc/pki/CA/certs/ca.crt
  # It's critical to enforce client certificates on the Master.  Otherwise
  # requests could spoof the X-Remote-User header by accessing the Master's
  # /oauth/authorize endpoint directly.
  SSLProxyMachineCertificateFile /etc/pki/tls/certs/authproxy.pem

  # Send all requests to the console
  RewriteEngine              On
  RewriteRule     ^/console(.*)$     https://%{HTTP_HOST}:8443/console$1 [R,L]

  # In order to using the challenging-proxy an X-Csrf-Token must be present.
  RewriteCond %{REQUEST_URI} ^/challenging-proxy
  RewriteCond %{HTTP:X-Csrf-Token} ^$ [NC]
  RewriteRule ^.* - [F,L]

  <Location /challenging-proxy/oauth/authorize>
    # Insert your backend server name/ip here.
    ProxyPass https://[MASTER]:8443/oauth/authorize
    AuthType basic
  </Location>

  <Location /login-proxy/oauth/authorize>
    # Insert your backend server name/ip here.
    ProxyPass https://[MASTER]:8443/oauth/authorize

    # mod_auth_form providers are implemented by mod_authn_dbm, mod_authn_file,
    # mod_authn_dbd, mod_authnz_ldap and mod_authn_socache.
    AuthFormProvider file
    AuthType form
    AuthName openshift
    ErrorDocument 401 /login.html
  </Location>

  <ProxyMatch /oauth/authorize>
    AuthUserFile /etc/origin/master/htpasswd
    AuthName openshift
    Require valid-user
    RequestHeader set X-Remote-User %{REMOTE_USER}s env=REMOTE_USER

    # For ldap:
    # AuthBasicProvider ldap
    # AuthLDAPURL "ldap://ldap.example.com:389/ou=People,dc=my-domain,dc=com?uid?sub?(objectClass=*)"

    # It's possible to remove the mod_auth_form usage and replace it with
    # something like mod_auth_kerb, mod_auth_gsspai or even mod_auth_mellon.
    # The former would be able to support both the login and challenge flows
    # from the Master.  Mellon would likely only support the login flow.

    # For Kerberos
    # yum install mod_auth_gssapi
    # AuthType GSSAPI
    # GssapiCredStore keytab:/etc/httpd.keytab
  </ProxyMatch>

</VirtualHost>

RequestHeader unset X-Remote-User

Additional mod_auth_form Requirements

A sample login page is available from the openshift_extras repository. This file should be placed in the DocumentRoot location (/var/www/html by default).

Creating Users

At this point, you can create the users in the system Apache is using to store accounts information. In this example, file-backed authentication is used:

# yum -y install httpd-tools
# touch /etc/origin/master/htpasswd
# htpasswd /etc/origin/master/htpasswd <user_name>

Configuring the Master

The identityProviders stanza in the /etc/origin/master/master-config.yaml file must be updated as well:

  identityProviders:
  - name: requestheader
    challenge: true
    login: true
    provider:
      apiVersion: v1
      kind: RequestHeaderIdentityProvider
      challengeURL: "https://[MASTER]/challenging-proxy/oauth/authorize?${query}"
      loginURL: "https://[MASTER]/login-proxy/oauth/authorize?${query}"
      clientCA: /etc/origin/master/proxyca.crt
      headers:
      - X-Remote-User

Restarting Services

Finally, restart the following services:

# systemctl restart httpd
# systemctl restart atomic-openshift-master

Verifying the Configuration

Test by bypassing the proxy. You should be able to request a token if you supply the correct client certificate and header:

# curl -L -k -H "X-Remote-User: joe" \
   --cert /etc/pki/tls/certs/authproxy.pem \
   https://[MASTER]:8443/oauth/token/request

If you do not supply the client certificate, the request should be denied:

# curl -L -k -H "X-Remote-User: joe" \
   https://[MASTER]:8443/oauth/token/request

This should show a redirect to the configured challengeURL (with additional query parameters):

# curl -k -v -H 'X-Csrf-Token: 1' \
   '<masterPublicURL>/oauth/authorize?client_id=openshift-challenging-client&response_type=token'

This should show a 401 response with a WWW-Authenticate basic challenge:

#  curl -k -v -H 'X-Csrf-Token: 1' \
    '<redirected challengeURL from step 3 +query>'

This should show a redirect with an access token:

#  curl -k -v -u <your_user>:<your_password> \
    -H 'X-Csrf-Token: 1' '<redirected_challengeURL_from_step_3 +query>'

GitHub

Set GitHubIdentityProvider in the identityProviders stanza to use GitHub as an identity provider, using the OAuth integration.

Note

Using GitHub as an identity provider requires users to get a token using <master>/oauth/token/request to use with command-line tools.

Warning

Using GitHub as an identity provider allows any GitHub user to authenticate to your server. You can limit authentication to members of specific GitHub organizations with the organizations configuration attribute, as shown below.

Example 12.10. Master Configuration Using GitHubIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: github
    challenge: false
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: GitHubIdentityProvider
      clientID: ...
      clientSecret: ...
      organizations:
      - myorganization1
      - myorganization2

This provider name is prefixed to the GitHub numeric user ID to form an identity name. It is also used to build the callback URL.

GitHubIdentityProvider cannot be used to send WWW-Authenticate challenges.

When true, unauthenticated token requests from web clients (like the web console) are redirected to GitHub to log in.

Controls how mappings are established between this provider’s identities and user objects, as described above.

The client ID of a registered GitHub OAuth application. The application must be configured with a callback URL of <master>/oauth2callback/<identityProviderName>.

The client secret issued by GitHub. This value may also be provided in an environment variable, external file, or encrypted file.

Optional list of organizations. If specified, only GitHub users that are members of at least one of the listed organizations will be allowed to log in. If the GitHub OAuth application configured in clientID is not owned by the organization, an organization owner must grant third-party access in order to use this option. This can be done during the first GitHub login by the organization’s administrator, or from the GitHub organization settings.

GitLab

Set GitLabIdentityProvider in the identityProviders stanza to use GitLab.com or any other GitLab instance as an identity provider, using the OAuth integration. The OAuth provider feature requires GitLab version 7.7.0 or higher.

Note

Using GitLab as an identity provider requires users to get a token using <master>/oauth/token/request to use with command-line tools.

Example 12.11. Master Configuration Using GitLabIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: gitlab
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: GitLabIdentityProvider
      url: ...
      clientID: ...
      clientSecret: ...
      ca: ...

This provider name is prefixed to the GitLab numeric user ID to form an identity name. It is also used to build the callback URL.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider. This uses the Resource Owner Password Credentials grant flow to obtain an access token from GitLab.

When true, unauthenticated token requests from web clients (like the web console) are redirected to GitLab to log in.

Controls how mappings are established between this provider’s identities and user objects, as described above.

The host URL of a GitLab OAuth provider. This could either be https://gitlab.com/ or any other self hosted instance of GitLab.

The client ID of a registered GitLab OAuth application. The application must be configured with a callback URL of <master>/oauth2callback/<identityProviderName>.

The client secret issued by GitLab. This value may also be provided in an environment variable, external file, or encrypted file.

CA is an optional trusted certificate authority bundle to use when making requests to the GitLab instance. If empty, the default system roots are used.

Google

Set GoogleIdentityProvider in the identityProviders stanza to use Google as an identity provider, using Google’s OpenID Connect integration.

Note

Using Google as an identity provider requires users to get a token using <master>/oauth/token/request to use with command-line tools.

Warning

Using Google as an identity provider allows any Google user to authenticate to your server. You can limit authentication to members of a specific hosted domain with the hostedDomain configuration attribute, as shown below.

Example 12.12. Master Configuration Using GoogleIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: google
    challenge: false
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: GoogleIdentityProvider
      clientID: ...
      clientSecret: ...
      hostedDomain: ""

This provider name is prefixed to the Google numeric user ID to form an identity name. It is also used to build the redirect URL.

GoogleIdentityProvider cannot be used to send WWW-Authenticate challenges.

When true, unauthenticated token requests from web clients (like the web console) are redirected to Google to log in.

Controls how mappings are established between this provider’s identities and user objects, as described above.

The client ID of a registered Google project. The project must be configured with a redirect URI of <master>/oauth2callback/<identityProviderName>.

The client secret issued by Google. This value may also be provided in an environment variable, external file, or encrypted file.

Optional hosted domain to restrict sign-in accounts to. If empty, any Google account is allowed to authenticate.

OpenID Connect

Set OpenIDIdentityProvider in the identityProviders stanza to integrate with an OpenID Connect identity provider using an Authorization Code Flow.

Note

ID Token and UserInfo decryptions are not supported.

By default, the openid scope is requested. If required, extra scopes can be specified in the extraScopes field.

Claims are read from the JWT id_token returned from the OpenID identity provider and, if specified, from the JSON returned by the UserInfo URL.

At least one claim must be configured to use as the user’s identity. The standard identity claim is sub.

You can also indicate which claims to use as the user’s preferred user name, display name, and email address. If multiple claims are specified, the first one with a non-empty value is used. The standard claims are:

sub

The user identity.

preferred_username

The preferred user name when provisioning a user.

email

Email address.

name

Display name.

Note

Using an OpenID Connect identity provider requires users to get a token using <master>/oauth/token/request to use with command-line tools.

Example 12.13. Standard Master Configuration Using OpenIDIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_openid_connect
    challenge: true
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: OpenIDIdentityProvider
      clientID: ...
      clientSecret: ...
      claims:
        id:
        - sub
        preferredUsername:
        - preferred_username
        name:
        - name
        email:
        - email
      urls:
        authorize: https://myidp.example.com/oauth2/authorize
        token: https://myidp.example.com/oauth2/token

This provider name is prefixed to the value of the identity claim to form an identity name. It is also used to build the redirect URL.

When true, unauthenticated token requests from non-web clients (like the CLI) are sent a WWW-Authenticate challenge header for this provider. This requires the OpenID provider to support the Resource Owner Password Credentials grant flow.

When true, unauthenticated token requests from web clients (like the web console) are redirected to the authorize URL to log in.

Controls how mappings are established between this provider’s identities and user objects, as described above.

The client ID of a client registered with the OpenID provider. The client must be allowed to redirect to <master>/oauth2callback/<identityProviderName>.

The client secret. This value may also be provided in an environment variable, external file, or encrypted file.

Use the value of the sub claim in the returned id_token as the user’s identity.

Authorization Endpoint described in the OpenID spec. Must use https.

Token Endpoint described in the OpenID spec. Must use https.

A custom certificate bundle, extra scopes, extra authorization request parameters, and userInfo URL can also be specified:

Example 12.14. Full Master Configuration Using OpenIDIdentityProvider

oauthConfig:
  ...
  identityProviders:
  - name: my_openid_connect
    challenge: false
    login: true
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: OpenIDIdentityProvider
      clientID: ...
      clientSecret: ...
      ca: my-openid-ca-bundle.crt
      extraScopes:
      - email
      - profile
      extraAuthorizeParameters:
        include_granted_scopes: "true"
      claims:
        id:
        - custom_id_claim
        - sub
        preferredUsername:
        - preferred_username
        - email
        name:
        - nickname
        - given_name
        - name
        email:
        - custom_email_claim
        - email
      urls:
        authorize: https://myidp.example.com/oauth2/authorize
        token: https://myidp.example.com/oauth2/token
        userInfo: https://myidp.example.com/oauth2/userinfo

Certificate bundle to use to validate server certificates for the configured URLs. If empty, system trusted roots are used.

Optional list of scopes to request, in addition to the openid scope, during the authorization token request.

Optional map of extra parameters to add to the authorization token request.

List of claims to use as the identity. First non-empty claim is used. At least one claim is required. If none of the listed claims have a value, authentication fails.

List of claims to use as the preferred user name when provisioning a user for this identity. First non-empty claim is used.

List of claims to use as the display name. First non-empty claim is used.

List of claims to use as the email address. First non-empty claim is used.

UserInfo Endpoint described in the OpenID spec. Must use https.

Token Options

The OAuth server generates two kinds of tokens:

Access tokens

Longer-lived tokens that grant access to the API.

Authorize codes

Short-lived tokens whose only use is to be exchanged for an access token.

Use the tokenConfig stanza to set token options:

Example 12.15. Master Configuration Token Options

oauthConfig:
  ...
  tokenConfig:
    accessTokenMaxAgeSeconds: 86400
    authorizeTokenMaxAgeSeconds: 300

Set accessTokenMaxAgeSeconds to control the lifetime of access tokens. The default lifetime is 24 hours.

Set authorizeTokenMaxAgeSeconds to control the lifetime of authorize codes. The default lifetime is five minutes.

Grant Options

When the OAuth server receives token requests for a client to which the user has not previously granted permission, the action that the OAuth server takes is dependent on the OAuth client’s grant strategy.

When the OAuth client requesting token does not provide its own grant strategy, the server-wide default strategy is used. To configure the default strategy, set the method value in the grantConfig stanza. Valid values for method are:

auto

Auto-approve the grant and retry the request.

prompt

Prompt the user to approve or deny the grant.

deny

Auto-deny the grant and return a failure error to the client.

Example 12.16. Master Configuration Grant Options

oauthConfig:
  ...
  grantConfig:
    method: auto

Session Options

The OAuth server uses a signed and encrypted cookie-based session during login and redirect flows.

Use the sessionConfig stanza to set session options:

Example 12.17. Master Configuration Session Options

oauthConfig:
  ...
  sessionConfig:
    sessionMaxAgeSeconds: 300
    sessionName: ssn
    sessionSecretsFile: "..."

Controls the maximum age of a session; sessions auto-expire once a token request is complete. If auto-grant is not enabled, sessions must last as long as the user is expected to take to approve or reject a client authorization request.

Name of the cookie used to store the session.

File name containing serialized SessionSecrets object. If empty, a random signing and encryption secret is generated at each server start.

If no sessionSecretsFile is specified, a random signing and encryption secret is generated at each start of the master server. This means that any logins in progress will have their sessions invalidated if the master is restarted. It also means that if multiple masters are configured, they will not be able to decode sessions generated by one of the other masters.

To specify the signing and encryption secret to use, specify a sessionSecretsFile. This allows you separate secret values from the configuration file and keep the configuration file distributable, for example for debugging purposes.

Multiple secrets can be specified in the sessionSecretsFile to enable rotation. New sessions are signed and encrypted using the first secret in the list. Existing sessions are decrypted and authenticated by each secret until one succeeds.

Example 12.18. Session Secret Configuration:

apiVersion: v1
kind: SessionSecrets
secrets:
- authentication: "..."
  encryption: "..."
- authentication: "..."
  encryption: "..."
...

List of secrets used to authenticate and encrypt cookie sessions. At least one secret must be specified. Each secret must set an authentication and encryption secret.

Signing secret, used to authenticate sessions using HMAC. Recommended to use a secret with 32 or 64 bytes.

Encrypting secret, used to encrypt sessions. Must be 16, 24, or 32 characters long, to select AES-128, AES-192, or AES-256.

Preventing CLI Version Mismatch With User Agent

OpenShift Container Platform implements a user agent that can be used to prevent an application developer’s CLI accessing the OpenShift Container Platform API.

User agents for the OpenShift Container Platform CLI are constructed from a set of values within OpenShift Container Platform:

<command>/<version> (<platform>/<architecture>) <client>/<git_commit>

So, for example, when:

<command> = oc

<version> = The client version. For example, v3.3.0. This can change depending on if the request is made against the Kubernetes API at /api, or the OpenShift Container Platform API at /oapi

<platform> = linux

<architecture> = amd64

<client> = openshift, or kubernetes depending on if the request is made against the Kubernetes API at /api, or the OpenShift Container Platform API at /oapi.

<git_commit> = The Git commit of the client version (for example, f034127)

the user agent will be:

oc/v3.3.0 (linux/amd64) openshift/f034127

As an OpenShift Container Platform administrator, you can prevent clients from accessing the API with the userAgentMatching configuration setting of a master configuration. So, if a client is using a particular library or binary, they will be prevented from accessing the API.

The following user agent example denies the Kubernetes 1.2 client binary, OpenShift Origin 1.1.3 binary, and the POST and PUT httpVerbs:

policyConfig:
  userAgentMatchingConfig:
    defaultRejectionMessage: "Your client is too old.  Go to https://example.org to update it."
    deniedClients:
    - regex: '\w+/v(?:(?:1\.1\.1)|(?:1\.0\.1)) \(.+/.+\) openshift/\w{7}'
    - regex: '\w+/v(?:1\.1\.3) \(.+/.+\) openshift/\w{7}'
      httpVerbs:
      - POST
      - PUT
    - regex: '\w+/v1\.2\.0 \(.+/.+\) kubernetes/\w{7}'
      httpVerbs:
      - POST
      - PUT
    requiredClients: null

Administrators can also deny clients that do not exactly match the expected clients:

policyConfig:
  userAgentMatchingConfig:
    defaultRejectionMessage: "Your client is too old.  Go to https://example.org to update it."
    deniedClients: []
    requiredClients:
    - regex: '\w+/v1\.1\.3 \(.+/.+\) openshift/\w{7}'
    - regex: '\w+/v1\.2\.0 \(.+/.+\) kubernetes/\w{7}'
      httpVerbs:
      - POST
      - PUT

Note

When the client’s user agent mismatches the configuration, errors occur. To ensure that mutating requests match, enforce a whitelist. Rules are mapped to specific verbs, so you can ban mutating requests while allowing non-mutating requests.

Chapter 13. Syncing Groups With LDAP

Overview

As an OpenShift Container Platform administrator, you can use groups to manage users, change their permissions, and enhance collaboration. Your organization may have already created user groups and stored them in an LDAP server. OpenShift Container Platform can sync those LDAP records with internal OpenShift Container Platform records, enabling you to manage your groups in one place. OpenShift Container Platform currently supports group sync with LDAP servers using three common schemas for defining group membership: RFC 2307, Active Directory, and augmented Active Directory.

Note

You must have cluster-admin privileges to sync groups.

Configuring LDAP Sync

Before you can run LDAP sync, you need a sync configuration file. This file contains LDAP client configuration details:

Configuration for connecting to your LDAP server.

Sync configuration options that are dependent on the schema used in your LDAP server.

A sync configuration file can also contain an administrator-defined list of name mappings that maps OpenShift Container Platform Group names to groups in your LDAP server.

LDAP Client Configuration

Example 13.1. LDAP Client Configuration

url: ldap://10.0.0.0:389
bindDN: cn=admin,dc=example,dc=com
bindPassword: password
insecure: true
ca: my-ldap-ca-bundle.crt

The connection protocol, IP address of the LDAP server hosting your database, and the port to connect to, formatted as scheme://host:port.

Optional distinguished name (DN) to use as the Bind DN. OpenShift Container Platform uses this if elevated privilege is required to retrieve entries for the sync operation.

Optional password to use to bind. OpenShift Container Platform uses this if elevated privilege is necessary to retrieve entries for the sync operation. This value may also be provided in an environment variable, external file, or encrypted file.

When true, no TLS connection is made to the server. When false, secure LDAP (ldaps://) URLs connect using TLS, and insecure LDAP (ldap://) URLs are upgraded to TLS.

The certificate bundle to use for validating server certificates for the configured URL. If empty, OpenShift Container Platform uses system-trusted roots. This only applies if insecure is set to false.

LDAP Query Definition

Sync configurations consist of LDAP query definitions for the entries that are required for synchronization. The specific definition of an LDAP query depends on the schema used to store membership information in the LDAP server.

Example 13.2. LDAP Query Definition

baseDN: ou=users,dc=example,dc=com
scope: sub
derefAliases: never
timeout: 0
filter: (objectClass=inetOrgPerson)
pageSize: 0

The distinguished name (DN) of the branch of the directory where all searches will start from. It is required that you specify the top of your directory tree, but you can also specify a subtree in the directory.

The scope of the search. Valid values are base, one, or sub. If this is left undefined, then a scope of sub is assumed. Descriptions of the scope options can be found in the table below.

The behavior of the search with respect to aliases in the LDAP tree. Valid values are never, search, base, or always. If this is left undefined, then the default is to always dereference aliases. Descriptions of the dereferencing behaviors can be found in the table below.

The time limit allowed for the search by the client, in seconds. A value of 0 imposes no client-side limit.

A valid LDAP search filter. If this is left undefined, then the default is (objectClass=*).

The optional maximum size of response pages from the server, measured in LDAP entries. If set to 0, no size restrictions will be made on pages of responses. Setting paging sizes is necessary when queries return more entries than the client or server allow by default.

Table 13.1. LDAP Search Scope Options

LDAP Search Scope
Description

base

Only consider the object specified by the base DN given for the query.

one

Consider all of the objects on the same level in the tree as the base DN for the query.

sub

Consider the entire subtree rooted at the base DN given for the query.

Table 13.2. LDAP Dereferencing Behaviors

Dereferencing Behavior
Description

never

Never dereference any aliases found in the LDAP tree.

search

Only dereference aliases found while searching.

base

Only dereference aliases while finding the base object.

always

Always dereference all aliases found in the LDAP tree.

User-Defined Name Mapping

A user-defined name mapping explicitly maps the names of OpenShift Container Platform Groups to unique identifiers that find groups on your LDAP server. The mapping uses normal YAML syntax. A user-defined mapping can contain an entry for every group in your LDAP server or only a subset of those groups. If there are groups on the LDAP server that do not have a user-defined name mapping, the default behavior during sync is to use the attribute specified as the Group’s name.

Example 13.3. User-Defined Name Mapping

groupUIDNameMapping:
  "cn=group1,ou=groups,dc=example,dc=com": firstgroup
  "cn=group2,ou=groups,dc=example,dc=com": secondgroup
  "cn=group3,ou=groups,dc=example,dc=com": thirdgroup

Running LDAP Sync

Once you have created a sync configuration file, then sync can begin. OpenShift Container Platform allows administrators to perform a number of different sync types with the same server.

Note

By default, all group synchronization or pruning operations are dry-run, so you must set the --confirm flag on the sync-groups command in order to make changes to OpenShift Container Platform Group records.

To sync all groups from the LDAP server with OpenShift Container Platform:

$ oadm groups sync --sync-config=config.yaml --confirm

To sync all Groups already in OpenShift Container Platform that correspond to groups in the LDAP server specified in the configuration file:

$ oadm groups sync --type=openshift --sync-config=config.yaml --confirm

To sync a subset of LDAP groups with OpenShift Container Platform, you can use whitelist files, blacklist files, or both:

Note

Any combination of blacklist files, whitelist files, or whitelist literals will work; whitelist literals can be included directly in the command itself. This applies to groups found on LDAP servers, as well as Groups already present in OpenShift Container Platform. Your files must contain one unique group identifier per line.

$ oadm groups sync --whitelist=<whitelist_file> \
                   --sync-config=config.yaml    \
                   --confirm
$ oadm groups sync --blacklist=<blacklist_file> \
                   --sync-config=config.yaml    \
                   --confirm
$ oadm groups sync <group_unique_identifier>    \
                   --sync-config=config.yaml    \
                   --confirm
$ oadm groups sync <group_unique_identifier>    \
                   --whitelist=<whitelist_file> \
                   --blacklist=<blacklist_file> \
                   --sync-config=config.yaml    \
                   --confirm
$ oadm groups sync --type=openshift             \
                   --whitelist=<whitelist_file> \
                   --sync-config=config.yaml    \
                   --confirm

Running a Group Pruning Job

An administrator can also choose to remove groups from OpenShift Container Platform records if the records on the LDAP server that created them are no longer present. The prune job will accept the same sync configuration file and white- or black-lists as used for the sync job.

For example, if groups had previously been synchronized from LDAP using some config.yaml file, and some of those groups no longer existed on the LDAP server, the following command would determine which Groups in OpenShift Container Platform corresponded to the deleted groups in LDAP and then remove them from OpenShift Container Platform:

$ oadm groups prune --sync-config=config.yaml --confirm

Sync Examples

This section contains examples for the RFC 2307, Active Directory, and augmented Active Directory schemas. All of the following examples synchronize a group named admins that has two members: Jane and Jim. Each example explains:

How the group and users are added to the LDAP server.

What the LDAP sync configuration file looks like.

What the resulting Group record in OpenShift Container Platform will be after synchronization.

RFC 2307

In the RFC 2307 schema, both users (Jane and Jim) and groups exist on the LDAP server as first-class entries, and group membership is stored in attributes on the group. The following snippet of ldif defines the users and group for this schema:

Example 13.4. LDAP Entries Using RFC 2307 Schema: rfc2307.ldif

  dn: ou=users,dc=example,dc=com
  objectClass: organizationalUnit
  ou: users

  dn: cn=Jane,ou=users,dc=example,dc=com
  objectClass: person
  objectClass: organizationalPerson
  objectClass: inetOrgPerson
  cn: Jane
  sn: Smith
  displayName: Jane Smith
  mail: jane.smith@example.com

  dn: cn=Jim,ou=users,dc=example,dc=com
  objectClass: person
  objectClass: organizationalPerson
  objectClass: inetOrgPerson
  cn: Jim
  sn: Adams
  displayName: Jim Adams
  mail: jim.adams@example.com

  dn: ou=groups,dc=example,dc=com
  objectClass: organizationalUnit
  ou: groups

  dn: cn=admins,ou=groups,dc=example,dc=com
  objectClass: groupOfNames
  cn: admins
  owner: cn=admin,dc=example,dc=com
  description: System Administrators
  member: cn=Jane,ou=users,dc=example,dc=com
  member: cn=Jim,ou=users,dc=example,dc=com

The group is a first-class entry in the LDAP server.

Members of a group are listed with an identifying reference as attributes on the group.

To sync this group, you must first create the configuration file. The RFC 2307 schema requires you to provide an LDAP query definition for both user and group entries, as well as the attributes with which to represent them in the internal OpenShift Container Platform records.

For clarity, the Group you create in OpenShift Container Platform should use attributes other than the distinguished name whenever possible for user- or administrator-facing fields. For example, identify the users of a Group by their e-mail, and use the name of the group as the common name. The following configuration file creates these relationships:

Note

If using user-defined name mappings, your configuration file will differ.

Example 13.5. LDAP Sync Configuration Using RFC 2307 Schema: rfc2307_config.yaml

kind: LDAPSyncConfig
apiVersion: v1
url: ldap://LDAP_SERVICE_IP:389
insecure: true
rfc2307:
    groupsQuery:
        baseDN: "ou=groups,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
    groupUIDAttribute: dn
    groupNameAttributes: [ cn ]
    groupMembershipAttributes: [ member ]
    usersQuery:
        baseDN: "ou=users,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
    userUIDAttribute: dn
    userNameAttributes: [ mail ]
    tolerateMemberNotFoundErrors: false
    tolerateMemberOutOfScopeErrors: false

The IP address and host of the LDAP server where this group’s record is stored.

When true, no TLS connection is made to the server. When false, secure LDAP (ldaps://) URLs connect using TLS, and insecure LDAP (ldap://) URLs are upgraded to TLS.

The attribute that uniquely identifies a group on the LDAP server. You cannot specify groupsQuery filters when using DN for groupUIDAttribute. For fine-grained filtering, use the whitelist / blacklist method.

The attribute to use as the name of the Group.

The attribute on the group that stores the membership information.

The attribute that uniquely identifies a user on the LDAP server. You cannot specify usersQuery filters when using DN for userUIDAttribute. For fine-grained filtering, use the whitelist / blacklist method.

The attribute to use as the name of the user in the OpenShift Container Platform Group record.

To run sync with the rfc2307_config.yaml file:

$ oadm groups sync --sync-config=rfc2307_config.yaml --confirm

OpenShift Container Platform creates the following Group record as a result of the above sync operation:

Example 13.6. OpenShift Container Platform Group Created Using rfc2307_config.yaml

apiVersion: v1
kind: Group
metadata:
  annotations:
    openshift.io/ldap.sync-time: 2015-10-13T10:08:38-0400
    openshift.io/ldap.uid: cn=admins,ou=groups,dc=example,dc=com
    openshift.io/ldap.url: LDAP_SERVER_IP:389
  creationTimestamp:
  name: admins
users:
- jane.smith@example.com
- jim.adams@example.com

The last time this Group was synchronized with the LDAP server, in ISO 6801 format.

The unique identifier for the group on the LDAP server.

The IP address and host of the LDAP server where this Group’s record is stored.

The name of the Group as specified by the sync file.

The users that are members of the Group, named as specified by the sync file.

RFC2307 with User-Defined Name Mappings

When syncing groups with user-defined name mappings, the configuration file changes to contain these mappings as shown below.

Example 13.7. LDAP Sync Configuration Using RFC 2307 Schema With User-Defined Name Mappings: rfc2307_config_user_defined.yaml

kind: LDAPSyncConfig
apiVersion: v1
groupUIDNameMapping:
  "cn=admins,ou=groups,dc=example,dc=com": Administrators
rfc2307:
    groupsQuery:
        baseDN: "ou=groups,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
    groupUIDAttribute: dn
    groupNameAttributes: [ cn ]
    groupMembershipAttributes: [ member ]
    usersQuery:
        baseDN: "ou=users,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
    userUIDAttribute: dn
    userNameAttributes: [ mail ]
    tolerateMemberNotFoundErrors: false
    tolerateMemberOutOfScopeErrors: false

The user-defined name mapping.

The unique identifier attribute that is used for the keys in the user-defined name mapping. You cannot specify groupsQuery filters when using DN for groupUIDAttribute. For fine-grained filtering, use the whitelist / blacklist method.

The attribute to name OpenShift Container Platform Groups with if their unique identifier is not in the user-defined name mapping.

The attribute that uniquely identifies a user on the LDAP server. You cannot specify usersQuery filters when using DN for userUIDAttribute. For fine-grained filtering, use the whitelist / blacklist method.

To run sync with the rfc2307_config_user_defined.yaml file:

$ oadm groups sync --sync-config=rfc2307_config_user_defined.yaml --confirm

OpenShift Container Platform creates the following Group record as a result of the above sync operation:

Example 13.8. OpenShift Container Platform Group Created Using rfc2307_config_user_defined.yaml

apiVersion: v1
kind: Group
metadata:
  annotations:
    openshift.io/ldap.sync-time: 2015-10-13T10:08:38-0400
    openshift.io/ldap.uid: cn=admins,ou=groups,dc=example,dc=com
    openshift.io/ldap.url: LDAP_SERVER_IP:389
  creationTimestamp:
  name: Administrators
users:
- jane.smith@example.com
- jim.adams@example.com

The name of the Group as specified by the user-defined name mapping.

RFC 2307 with User-Defined Error Tolerances

By default, if the groups being synced contain members whose entries are outside of the scope defined in the member query, the group sync fails with an error:

Error determining LDAP group membership for "<group>": membership lookup for user "<user>" in group "<group>" failed because of "search for entry with dn="<user-dn>" would search outside of the base dn specified (dn="<base-dn>")".

This often indicates a mis-configured baseDN in the usersQuery field. However, in cases where the baseDN intentionally does not contain some of the members of the group, setting tolerateMemberOutOfScopeErrors: true allows the group sync to continue. Out of scope members will be ignored.

Similarly, when the group sync process fails to locate a member for a group, it fails outright with errors:

Error determining LDAP group membership for "<group>": membership lookup for user "<user>" in group "<group>" failed because of "search for entry with base dn="<user-dn>" refers to a non-existent entry".

Error determining LDAP group membership for "<group>": membership lookup for user "<user>" in group "<group>" failed because of "search for entry with base dn="<user-dn>" and filter "<filter>" did not return any results".

This often indicates a mis-configured usersQuery field. However, in cases where the group contains member entries that are known to be missing, setting tolerateMemberNotFoundErrors: true allows the group sync to continue. Problematic members will be ignored.

Warning

Enabling error tolerances for the LDAP group sync causes the sync process to ignore problematic member entries. If the LDAP group sync is not configured correctly, this could result in synced OpenShift Container Platform groups missing members.

Example 13.9. LDAP Entries Using RFC 2307 Schema With Problematic Group Membership: rfc2307_problematic_users.ldif

  dn: ou=users,dc=example,dc=com
  objectClass: organizationalUnit
  ou: users

  dn: cn=Jane,ou=users,dc=example,dc=com
  objectClass: person
  objectClass: organizationalPerson
  objectClass: inetOrgPerson
  cn: Jane
  sn: Smith
  displayName: Jane Smith
  mail: jane.smith@example.com

  dn: cn=Jim,ou=users,dc=example,dc=com
  objectClass: person
  objectClass: organizationalPerson
  objectClass: inetOrgPerson
  cn: Jim
  sn: Adams
  displayName: Jim Adams
  mail: jim.adams@example.com

  dn: ou=groups,dc=example,dc=com
  objectClass: organizationalUnit
  ou: groups

  dn: cn=admins,ou=groups,dc=example,dc=com
  objectClass: groupOfNames
  cn: admins
  owner: cn=admin,dc=example,dc=com
  description: System Administrators
  member: cn=Jane,ou=users,dc=example,dc=com
  member: cn=Jim,ou=users,dc=example,dc=com
  member: cn=INVALID,ou=users,dc=example,dc=com
  member: cn=Jim,ou=OUTOFSCOPE,dc=example,dc=com

A member that does not exist on the LDAP server.

A member that may exist, but is not under the baseDN in the user query for the sync job.

In order to tolerate the errors in the above example, the following additions to your sync configuration file must be made:

Example 13.10. LDAP Sync Configuration Using RFC 2307 Schema Tolerating Errors: rfc2307_config_tolerating.yaml

kind: LDAPSyncConfig
apiVersion: v1
url: ldap://LDAP_SERVICE_IP:389
insecure: true
rfc2307:
    groupsQuery:
        baseDN: "ou=groups,dc=example,dc=com"
        scope: sub
        derefAliases: never
    groupUIDAttribute: dn
    groupNameAttributes: [ cn ]
    groupMembershipAttributes: [ member ]
    usersQuery:
        baseDN: "ou=users,dc=example,dc=com"
        scope: sub
        derefAliases: never
    userUIDAttribute: dn
    userNameAttributes: [ mail ]
    tolerateMemberNotFoundErrors: true
    tolerateMemberOutOfScopeErrors: true

When true, the sync job tolerates groups for which some members were not found, and members whose LDAP entries are not found are ignored. The default behavior for the sync job is to fail if a member of a group is not found.

When true, the sync job tolerates groups for which some members are outside the user scope given in the usersQuery base DN, and members outside the member query scope are ignored. The default behavior for the sync job is to fail if a member of a group is out of scope.

The attribute that uniquely identifies a user on the LDAP server. You cannot specify usersQuery filters when using DN for userUIDAttribute. For fine-grained filtering, use the whitelist / blacklist method.

To run sync with the rfc2307_config_tolerating.yaml file:

$ oadm groups sync --sync-config=rfc2307_config_tolerating.yaml --confirm

OpenShift Container Platform creates the following group record as a result of the above sync operation:

Example 13.11. OpenShift Container Platform Group Created Using rfc2307_config.yaml

apiVersion: v1
kind: Group
metadata:
  annotations:
    openshift.io/ldap.sync-time: 2015-10-13T10:08:38-0400
    openshift.io/ldap.uid: cn=admins,ou=groups,dc=example,dc=com
    openshift.io/ldap.url: LDAP_SERVER_IP:389
  creationTimestamp:
  name: admins
users:
- jane.smith@example.com
- jim.adams@example.com

The users that are members of the group, as specified by the sync file. Members for which lookup encountered tolerated errors are absent.

Active Directory

In the Active Directory schema, both users (Jane and Jim) exist in the LDAP server as first-class entries, and group membership is stored in attributes on the user. The following snippet of ldif defines the users and group for this schema:

Example 13.12. LDAP Entries Using Active Directory Schema: active_directory.ldif

dn: ou=users,dc=example,dc=com
objectClass: organizationalUnit
ou: users

dn: cn=Jane,ou=users,dc=example,dc=com
objectClass: person
objectClass: organizationalPerson
objectClass: inetOrgPerson
objectClass: testPerson
cn: Jane
sn: Smith
displayName: Jane Smith
mail: jane.smith@example.com
testMemberOf: admins

dn: cn=Jim,ou=users,dc=example,dc=com
objectClass: person
objectClass: organizationalPerson
objectClass: inetOrgPerson
objectClass: testPerson
cn: Jim
sn: Adams
displayName: Jim Adams
mail: jim.adams@example.com
testMemberOf: admins

The user’s group memberships are listed as attributes on the user, and the group does not exist as an entry on the server. The testMemberOf attribute cannot be a literal attribute on the user; it can be created during search and returned to the client, but not committed to the database.

To sync this group, you must first create the configuration file. The Active Directory schema requires you to provide an LDAP query definition for user entries, as well as the attributes to represent them with in the internal OpenShift Container Platform Group records.

For clarity, the Group you create in OpenShift Container Platform should use attributes other than the distinguished name whenever possible for user- or administrator-facing fields. For example, identify the users of a Group by their e-mail, but define the name of the Group by the name of the group on the LDAP server. The following configuration file creates these relationships:

Example 13.13. LDAP Sync Configuration Using Active Directory Schema: active_directory_config.yaml

kind: LDAPSyncConfig
apiVersion: v1
url: ldap://LDAP_SERVICE_IP:389
insecure: true
activeDirectory:
    usersQuery:
        baseDN: "ou=users,dc=example,dc=com"
        scope: sub
        derefAliases: never
        filter: (objectclass=inetOrgPerson)
        pageSize: 0
    userNameAttributes: [ mail ]
    groupMembershipAttributes: [ testMemberOf ]

The attribute to use as the name of the user in the OpenShift Container Platform Group record.

The attribute on the user that stores the membership information.

To run sync with the active_directory_config.yaml file:

$ oadm groups sync --sync-config=active_directory_config.yaml --confirm

OpenShift Container Platform creates the following Group record as a result of the above sync operation:

Example 13.14. OpenShift Container Platform Group Created Using active_directory_config.yaml

apiVersion: v1
kind: Group
metadata:
  annotations:
    openshift.io/ldap.sync-time: 2015-10-13T10:08:38-0400
    openshift.io/ldap.uid: admins
    openshift.io/ldap.url: LDAP_SERVER_IP:389
  creationTimestamp:
  name: admins
users:
- jane.smith@example.com
- jim.adams@example.com

The last time this Group was synchronized with the LDAP server, in ISO 6801 format.

The unique identifier for the group on the LDAP server.

The IP address and host of the LDAP server where this Group’s record is stored.

The name of the group as listed in the LDAP server.

The users that are members of the Group, named as specified by the sync file.

Augmented Active Directory

In the augmented Active Directory schema, both users (Jane and Jim) and groups exist in the LDAP server as first-class entries, and group membership is stored in attributes on the user. The following snippet of ldif defines the users and group for this schema:

Example 13.15. LDAP Entries Using Augmented Active Directory Schema: augmented_active_directory.ldif

dn: ou=users,dc=example,dc=com
objectClass: organizationalUnit
ou: users

dn: cn=Jane,ou=users,dc=example,dc=com
objectClass: person
objectClass: organizationalPerson
objectClass: inetOrgPerson
objectClass: testPerson
cn: Jane
sn: Smith
displayName: Jane Smith
mail: jane.smith@example.com
testMemberOf: cn=admins,ou=groups,dc=example,dc=com

dn: cn=Jim,ou=users,dc=example,dc=com
objectClass: person
objectClass: organizationalPerson
objectClass: inetOrgPerson
objectClass: testPerson
cn: Jim
sn: Adams
displayName: Jim Adams
mail: jim.adams@example.com
testMemberOf: cn=admins,ou=groups,dc=example,dc=com

dn: ou=groups,dc=example,dc=com
objectClass: organizationalUnit
ou: groups

dn: cn=admins,ou=groups,dc=example,dc=com
objectClass: groupOfNames
cn: admins
owner: cn=admin,dc=example,dc=com
description: System Administrators
member: cn=Jane,ou=users,dc=example,dc=com
member: cn=Jim,ou=users,dc=example,dc=com

The user’s group memberships are listed as attributes on the user.

The group is a first-class entry on the LDAP server.

To sync this group, you must first create the configuration file. The augmented Active Directory schema requires you to provide an LDAP query definition for both user entries and group entries, as well as the attributes with which to represent them in the internal OpenShift Container Platform Group records.

For clarity, the Group you create in OpenShift Container Platform should use attributes other than the distinguished name whenever possible for user- or administrator-facing fields. For example, identify the users of a Group by their e-mail, and use the name of the Group as the common name. The following configuration file creates these relationships.

Example 13.16. LDAP Sync Configuration Using Augmented Active Directory Schema: augmented_active_directory_config.yaml

kind: LDAPSyncConfig
apiVersion: v1
url: ldap://LDAP_SERVICE_IP:389
insecure: true
augmentedActiveDirectory:
    groupsQuery:
        baseDN: "ou=groups,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
    groupUIDAttribute: dn
    groupNameAttributes: [ cn ]
    usersQuery:
        baseDN: "ou=users,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
    userNameAttributes: [ mail ]
    groupMembershipAttributes: [ testMemberOf ]

The attribute that uniquely identifies a group on the LDAP server. You cannot specify groupsQuery filters when using DN for groupUIDAttribute. For fine-grained filtering, use the whitelist / blacklist method.

The attribute to use as the name of the Group.

The attribute to use as the name of the user in the OpenShift Container Platform Group record.

The attribute on the user that stores the membership information.

To run sync with the augmented_active_directory_config.yaml file:

$ oadm groups sync --sync-config=augmented_active_directory_config.yaml --confirm

OpenShift Container Platform creates the following Group record as a result of the above sync operation:

Example 13.17. OpenShift Group Created Using augmented_active_directory_config.yaml

apiVersion: v1
kind: Group
metadata:
  annotations:
    openshift.io/ldap.sync-time: 2015-10-13T10:08:38-0400
    openshift.io/ldap.uid: cn=admins,ou=groups,dc=example,dc=com
    openshift.io/ldap.url: LDAP_SERVER_IP:389
  creationTimestamp:
  name: admins
users:
- jane.smith@example.com
- jim.adams@example.com

The last time this Group was synchronized with the LDAP server, in ISO 6801 format.

The unique identifier for the group on the LDAP server.

The IP address and host of the LDAP server where this Group’s record is stored.

The name of the Group as specified by the sync file.

The users that are members of the Group, named as specified by the sync file.

Chapter 14. Advanced LDAP Configuration

Overview

OpenShift Container Platform Advanced Lightweight Directory Access Protocol (LDAP) Configuration covers the following topics:

Setting up SSSD for LDAP Failover

Configuring Form-Based Authentication

Configuring Extended LDAP Attributes

Setting up SSSD for LDAP Failover

Overview

OpenShift Container Platform provides an authentication provider for use with Lightweight Directory Access Protocol (LDAP) setups, but it can only connect to a single LDAP server. This can be problematic if that LDAP server becomes unavailable. System Security Services Daemon (SSSD) can be used to solve the issue.

Originally designed to manage local and remote authentication to the host operating system, SSSD can now be configured to provide identity, authentication, and authorization services to web services like OpenShift Container Platform. SSSD provides advantages over the built-in LDAP provider, including the ability to connect to any number of failover LDAP servers, as well as the ability to cache authentication attempts in case it can no longer reach any of those servers.

The setup for this configuration is advanced and requires a separate authentication server (also called an authenticating proxy) for OpenShift Container Platform to communicate with. This topic describes how to do this setup on a dedicated physical or virtual machine (VM), but the concepts are also applicable to a setup in a container.

Prerequisites for Authenticating Proxy Setup

Before starting setup, you need to know the following information about your LDAP server.

Whether the directory server is powered by FreeIPA, Active Directory, or another LDAP solution.

The Uniform Resource Identifier (URI) for the LDAP server (for example, ldap.example.com).

The location of the CA certificate for the LDAP server.

Whether the LDAP server corresponds to RFC 2307 or RFC2307bis for user groups.

Prepare the VMs:

proxy.example.com: A VM to use as the authenticating proxy. This machine must have at least SSSD 1.12.0 available, which means a fairly recent operating system. This topic uses a Red Hat Enterprise Linux 7.2 server for its examples.

openshift.example.com: A VM to use to run OpenShift Container Platform.

Note

These VMs can be configured to run on the same system, but for the examples used in this topic they are kept separate.

Phase 1: Certificate Generation

To ensure that communication between the authenticating proxy and OpenShift Container Platform is trustworthy, create a set of Transport Layer Security (TLS) certificates to use during the other phases of this setup. In the OpenShift Container Platform system, start by using the auto-generated certificates created as part of running:

# openshift start \
    --public-master=https://openshift.example.com:8443 \
    --write-config=/etc/origin/

Among other things, this generates a /etc/origin/master/ca.{cert|key}. Use this signing certificate to generate keys to use on the authenticating proxy.

# mkdir -p /etc/origin/proxy/
# oadm ca create-server-cert \
    --cert='/etc/origin/proxy/proxy.example.com.crt' \
    --key='/etc/origin/proxy/proxy.example.com.key' \
    --hostnames=proxy.example.com \
    --signer-cert=/etc/origin/master/ca.crt \
    --signer-key='/etc/origin/master/ca.key' \
    --signer-serial='/etc/origin/master/ca.serial.txt'

Important

Ensure that any host names and interface IP addresses that need to access the proxy are listed. Otherwise, the HTTPS connection will fail.

Create a new CA to sign this client certificate:

# oadm ca create-signer-cert \
  --cert='/etc/origin/proxy/proxyca.crt' \
  --key='/etc/origin/proxy/proxyca.key' \
  --name='openshift-proxy-signer@UNIQUESTRING' \
  --serial='/etc/origin/proxy/proxyca.serial.txt'

Make UNIQUESTRING something unique.

Generate the API client certificate that the authenticating proxy will use to prove its identity to OpenShift Container Platform.

# oadm create-api-client-config \
    --certificate-authority='/etc/origin/proxy/proxyca.crt' \
    --client-dir='/etc/origin/proxy' \
    --signer-cert='/etc/origin/proxy/proxyca.crt' \
    --signer-key='/etc/origin/proxy/proxyca.key' \
    --signer-serial='/etc/origin/proxy/proxyca.serial.txt' \
    --user='system:proxy'

This prevents malicious users from impersonating the proxy and sending fake identities.

Copy the certificate and key information to the appropriate file for future steps:

# cat /etc/origin/proxy/system\:proxy.crt \
      /etc/origin/proxy/system\:proxy.key \
      > /etc/origin/proxy/authproxy.pem

Phase 2: Authenticating Proxy Setup

This section guides you through the steps to authenticate the proxy setup.

Step 1: Copy Certificates

From openshift.example.com, securely copy the necessary certificates to the proxy machine:

# scp /etc/origin/master/ca.crt \
      root@proxy.example.com:/etc/pki/CA/certs/

# scp /etc/origin/proxy/proxy.example.com.crt \
      /etc/origin/proxy/authproxy.pem \
      root@proxy.example.com:/etc/pki/tls/certs/

# scp /etc/origin/proxy/proxy.example.com.key \
      root@proxy.example.com:/etc/pki/tls/private/

Step 2: SSSD Configuration

Install a new VM with an operating system that includes 1.12.0 or later so that you can use the mod_identity_lookup module. The examples in this topic use a Red Hat Enterprise Linux 7.2 Server.

Install all of the necessary dependencies:

# yum install -y sssd \
                 sssd-dbus \
                 realmd \
                 httpd \
                 mod_session \
                 mod_ssl \
                 mod_lookup_identity \
                 mod_authnz_pam

This gives you the needed SSSD and the web server components.

Edit the /etc/httpd/conf.modules.d/55-authnz_pam.conf file and remove the comment from the following:

LoadModule authnz_pam_module modules/mod_authnz_pam.so

Set up SSSD to authenticate this VM against the LDAP server. If the LDAP server is a FreeIPA or Active Directory environment, then realmd can be used to join this machine to the domain.

# realm join ldap.example.com

For more advanced case, see the System-Level Authentication Guide

If you want to use SSSD to manage failover situations for LDAP, this can be configured by adding additional entries in /etc/sssd/sssd.conf on the ldap_uri line. Systems enrolled with FreeIPA can automatically handle failover using DNS SRV records.

Restart SSSD to ensure that all of the changes are applied properly:

$ systemctl restart sssd.service

Test that the user information can be retrieved properly:

$ getent passwd <username>
username:*:12345:12345:Example User:/home/username:/usr/bin/bash

Attempt to log into the VM as an LDAP user and confirm that the authentication is properly set up. This can be done via the local console or a remote service such as SSH.

Note

If you do not want LDAP users to be able to log into this machine, it is recommended to modify /etc/pam.d/system-auth and /etc/pam.d/password-auth to remove the lines containing pam_sss.so.

Step 3: Apache Configuration

You need to set up Apache to communicate with SSSD. Create a PAM stack file for use with Apache. To do so:

Create the /etc/pam.d/openshift file and add the following contents:

auth required pam_sss.so
account required pam_sss.so

This configuration enables PAM (the pluggable authentication module) to use pam_sss.so to determine authentication and access control when an authentication request is issued for the openshift stack.

Configure the Apache httpd.conf. The steps in this section focus on setting up the challenge authentication, which is useful for logging in with oc login and similar automated tools.

Note

Configuring Form-Based Authentication explains how to set up a graphical login using SSSD as well, but it requires the rest of this setup as a prerequisite.

Create the new file openshift-proxy.conf in /etc/httpd/conf.d (substituting the correct host names where indicated):

LoadModule request_module modules/mod_request.so
LoadModule lookup_identity_module modules/mod_lookup_identity.so
# Nothing needs to be served over HTTP.  This virtual host simply redirects to
# HTTPS.
<VirtualHost *:80>
  DocumentRoot /var/www/html
  RewriteEngine              On
  RewriteRule     ^(.*)$     https://%{HTTP_HOST}$1 [R,L]
</VirtualHost>

<VirtualHost *:443>
  # This needs to match the certificates you generated.  See the CN and X509v3
  # Subject Alternative Name in the output of:
  # openssl x509 -text -in /etc/pki/tls/certs/proxy.example.com.crt
  ServerName proxy.example.com

  DocumentRoot /var/www/html
  SSLEngine on
  SSLCertificateFile /etc/pki/tls/certs/proxy.example.com.crt
  SSLCertificateKeyFile /etc/pki/tls/private/proxy.example.com.key
  SSLCACertificateFile /etc/pki/CA/certs/ca.crt

  # Send logs to a specific location to make them easier to find
  ErrorLog logs/proxy_error_log
  TransferLog logs/proxy_access_log
  LogLevel warn
  SSLProxyEngine on
  SSLProxyCACertificateFile /etc/pki/CA/certs/ca.crt
  # It's critical to enforce client certificates on the Master.  Otherwise
  # requests could spoof the X-Remote-User header by accessing the Master's
  # /oauth/authorize endpoint directly.
  SSLProxyMachineCertificateFile /etc/pki/tls/certs/authproxy.pem

  # Send all requests to the console
  RewriteEngine              On
  RewriteRule     ^/console(.*)$     https://%{HTTP_HOST}:8443/console$1 [R,L]

  # In order to using the challenging-proxy an X-Csrf-Token must be present.
  RewriteCond %{REQUEST_URI} ^/challenging-proxy
  RewriteCond %{HTTP:X-Csrf-Token} ^$ [NC]
  RewriteRule ^.* - [F,L]

  <Location /challenging-proxy/oauth/authorize>
    # Insert your backend server name/ip here.
    ProxyPass https://openshift.example.com:8443/oauth/authorize
    AuthType Basic
    AuthBasicProvider PAM
    AuthPAMService openshift
    Require valid-user
  </Location>

  <ProxyMatch /oauth/authorize>
    AuthName openshift
    RequestHeader set X-Remote-User %{REMOTE_USER}s env=REMOTE_USER
  </ProxyMatch>
</VirtualHost>

RequestHeader unset X-Remote-User

Note

Configuring Form-Based Authentication explains how to add the login-proxy block to support form authentication.

Set a boolean to tell SELinux that it is acceptable for Apache to contact the PAM subsystem:

# setsebool -P allow_httpd_mod_auth_pam on

Start up Apache:

# systemctl start httpd.service

Phase 3: OpenShift Container Platform Configuration

This section describes how to set up an OpenShift Container Platform server from scratch in an "all in one" configuration. Master and Node Configuration provides more information on alternate configurations.

Modify the default configuration to use the new identity provider just created. To do so:

Modify the /etc/origin/master/master-config.yaml file.

Scan through it and locate the identityProviders section and replace it with:

  identityProviders:
  - name: any_provider_name
    challenge: true
    login: false
    mappingMethod: claim
    provider:
      apiVersion: v1
      kind: RequestHeaderIdentityProvider
      challengeURL: "https://proxy.example.com/challenging-proxy/oauth/authorize?${query}"
      clientCA: /etc/origin/proxy/proxyca.crt
      headers:
      - X-Remote-User

Note

Configuring Form-Based Authentication explains how to add the login URL to support web logins.

Configuring Extended LDAP Attributes explains how to add the email and full-name attributes. Note that the full-name attributes are only stored to the database on the first login.

Start OpenShift Container Platform with the updated configuration:

# openshift start \
    --public-master=https://openshift.example.com:8443 \
    --master-config=/etc/origin/master/master-config.yaml \
    --node-config=/etc/origin/node-node1.example.com/node-config.yaml

Test logins:

oc login https://openshift.example.com:8443

It should now be possible to log in with only valid LDAP credentials.

Configuring Form-Based Authentication

Overview

This topic builds upon Setting up SSSD for LDAP Failover and describes how to set up form-based authentication for signing into the OpenShift Container Platform web console.

Prepare a Login Page

The OpenShift Container Platform upstream repositories have a template for forms. Copy that to your authenticating proxy on proxy.example.com:

# curl -o /var/www/html/login.html \
    https://raw.githubusercontent.com/openshift/openshift-extras/master/misc/form_auth/login.html

Modify this .html file to change the logo icon and "Welcome" content for your environment.

Install Another Apache Module

To intercept form-based authentication, install an Apache module:

 # yum -y install mod_intercept_form_submit

Apache Configuration

Modify /etc/httpd/conf.modules.d/55-intercept_form_submit.conf and uncomment the LoadModule line.

Add a new section to your openshift-proxy.conf file inside the <VirtualHost *:443> block.

 <Location /login-proxy/oauth/authorize>
  # Insert your backend server name/ip here.
  ProxyPass https://openshift.example.com:8443/oauth/authorize

  InterceptFormPAMService openshift
  InterceptFormLogin httpd_username
  InterceptFormPassword httpd_password

  RewriteCond %{REQUEST_METHOD} GET
  RewriteRule ^.*$ /login.html [L]
</Location>

This tells Apache to listen for POST requests on the /login-proxy/oauth/authorize and to pass the user name and password over to the openshift PAM service.

Restart the service and move back over to the OpenShift Container Platform configuration.

OpenShift Container Platform Configuration

In the master-config.yaml file, update the identityProviders section:

identityProviders:
- name: any_provider_name
  challenge: true
  login: true
  mappingMethod: claim
  provider:
    apiVersion: v1
    kind: RequestHeaderIdentityProvider
    challengeURL: "https://proxy.example.com/challenging-proxy/oauth/authorize?${query}"
    loginURL: "https://proxy.example.com/login-proxy/oauth/authorize?${query}"
    clientCA: /etc/origin/master/proxy/proxyca.crt
    headers:
    - X-Remote-User

Note that login is set to true, not false.

Newly added line.

Restart OpenShift Container Platform with the updated configuration.

Note

You should be able to browse to https://openshift.example.com:8443 and use your LDAP credentials to sign in via the login form.

Configuring Extended LDAP Attributes

Overview

This topic builds upon Setting up SSSD for LDAP Failover and Configuring Form-Based Authentication and focuses on configuring extended Lightweight Directory Access Protocol (LDAP) attributes.

Prerequisites

SSSD 1.12.0 or later. This is available on Red Hat Enterprise Linux 7.0 and later.

mod_lookup_identity 0.9.4 or later.

The required version is not yet available on any version of Red Hat Enterprise Linux. However, compatible packages (RPMs) are available from upstream until they arrive in Red Hat Enterprise Linux.

Configuring SSSD

You need to ask System Security Services Daemon (SSSD) to look up attributes in LDAP that it normally does not care about for simple system-login use-cases. In the case of OpenShift Container Platform, there is only one such attribute: email. So, you need to:

Modify the [domain/DOMAINNAME] section of /etc/sssd/sssd.conf on the authenticating proxy and add this attribute:

[domain/example.com]
...
ldap_user_extra_attrs = mail

Tell SSSD that it is acceptable for this attribute to be retrieved by Apache. Add the following two lines to the [ifp] section of /etc/sssd/sssd.conf:

[ifp]
user_attributes = +mail
allowed_uids = apache, root

Restart SSSD:

# systemctl restart sssd.service

Test this configuration.

Configuring Apache

Now that SSSD is set up and successfully serving extended attributes, configure the web server to ask for them and to insert them in the correct places.

Enable the module to be loaded by Apache. To do so, modify /etc/httpd/conf.modules.d/55-lookup_identity.conf and uncomment the line:

LoadModule lookup_identity_module modules/mod_lookup_identity.so

Set an SELinux boolean so that SElinux allows Apache to connect to SSSD over D-BUS:

# setsebool -P httpd_dbus_sssd on

Edit /etc/httpd/conf.d/openshift-proxy.conf and add the following lines inside the <ProxyMatch /oauth/authorize> section:

<ProxyMatch /oauth/authorize>
  AuthName openshift

  LookupOutput Headers
  LookupUserAttr mail X-Remote-User-Email
  LookupUserGECOS X-Remote-User-Display-Name

  RequestHeader set X-Remote-User %{REMOTE_USER}s env=REMOTE_USER
</ProxyMatch>

Added line.

Restart Apache to pick up the changes:

# systemctl restart httpd.service

Configuring OpenShift Container Platform

Tell OpenShift Container Platform where to find these new attributes during login. To do so:

Edit the /etc/origin/master/master-config.yaml file and add the following lines to the identityProviders section:

identityProviders:
 - name: sssd
 challenge: true
 login: true
 mappingMethod: claim
 provider:
   apiVersion: v1
   kind: RequestHeaderIdentityProvider
   challengeURL: "https://proxy.example.com/challenging-proxy/oauth/authorize?${query}"
   loginURL: "https://proxy.example.com/login-proxy/oauth/authorize?${query}"
   clientCA: /home/example/workspace/openshift/configs/openshift.example.com/proxy/proxyca.crt
   headers:
   - X-Remote-User
   emailHeaders:
   - X-Remote-User-Email
   nameHeaders:
   - X-Remote-User-Display-Name

Added line.

Launch OpenShift Container Platform with this updated configuration and log in to the web as a new user.

You should see their full name appear in the upper-right of the screen. You can also verify with oc get identities -o yaml that both email addresses and full names are available.

Debugging Notes

Currently, OpenShift Container Platform only saves these attributes to the user at the time of the first login and does not update them again after that. So, while you are testing (and only while testing), run oc delete users,identities --all to clear the identities out so you can log in again.

Chapter 15. Configuring the SDN

Overview

The OpenShift Container Platform SDN enables communication between pods across the OpenShift Container Platform cluster, establishing a pod network. Two SDN plug-ins are currently available (ovs-subnet and ovs-multitenant), which provide different methods for configuring the pod network.

Configuring the Pod Network with Ansible

For initial advanced installations, the ovs-subnet plug-in is installed and configured by default, though it can be overridden during installation using the os_sdn_network_plugin_name parameter, which is configurable in the Ansible inventory file.

Example 15.1. Example SDN Configuration with Ansible

# Configure the multi-tenant SDN plugin (default is 'redhat/openshift-ovs-subnet')
# os_sdn_network_plugin_name='redhat/openshift-ovs-multitenant'

# Disable the OpenShift SDN plugin
# openshift_use_openshift_sdn=False

# Configure SDN cluster network CIDR block. This network block should
# be a private block and should not conflict with existing network
# blocks in your infrastructure that pods may require access to.
# Can not be changed after deployment.
#osm_cluster_network_cidr=10.1.0.0/16

# default subdomain to use for exposed routes
#openshift_master_default_subdomain=apps.test.example.com

# Configure SDN cluster network and kubernetes service CIDR blocks. These
# network blocks should be private and should not conflict with network blocks
# in your infrastructure that pods may require access to. Can not be changed
# after deployment.
#osm_cluster_network_cidr=10.1.0.0/16
#openshift_portal_net=172.30.0.0/16

# Configure number of bits to allocate to each host’s subnet e.g. 8
# would mean a /24 network on the host.
#osm_host_subnet_length=8

# This variable specifies the service proxy implementation to use:
# either iptables for the pure-iptables version (the default),
# or userspace for the userspace proxy.
#openshift_node_proxy_mode=iptables

For initial quick installations, the ovs-subnet plug-in is installed and configured by default as well, and can be reconfigured post-installation using the networkConfig stanza of the master-config.yaml file.

Configuring the Pod Network on Masters

Cluster administrators can control pod network settings on masters by modifying parameters in the networkConfig section of the master configuration file (located at /etc/origin/master/master-config.yaml by default):

networkConfig:
  clusterNetworkCIDR: 10.128.0.0/14
  hostSubnetLength: 9
  networkPluginName: "redhat/openshift-ovs-subnet"
  serviceNetworkCIDR: 172.30.0.0/16

Cluster network for node IP allocation

Number of bits for pod IP allocation within a node

Set to redhat/openshift-ovs-subnet for the ovs-subnet plug-in or redhat/openshift-ovs-multitenant for the ovs-multitenant plug-in

Service IP allocation for the cluster

Important

The serviceNetworkCIDR and hostSubnetLength values cannot be changed after the cluster is first created, and clusterNetworkCIDR can only be changed to be a larger network that still contains the original network. For example, given the default value of 10.128.0.0/14, you could change clusterNetworkCIDR to 10.128.0.0/9 (i.e., the entire upper half of net 10) but not to 10.64.0.0/16, because that does not overlap the original value.

Configuring the Pod Network on Nodes

Cluster administrators can control pod network settings on nodes by modifying parameters in the networkConfig section of the node configuration file (located at /etc/origin/node/node-config.yaml by default):

networkConfig:
  mtu: 1450
  networkPluginName: "redhat/openshift-ovs-subnet"

Maximum transmission unit (MTU) for the pod overlay network

Set to redhat/openshift-ovs-subnet for the ovs-subnet plug-in or redhat/openshift-ovs-multitenant for the ovs-multitenant plug-in

Migrating Between SDN Plug-ins

If you are already using one SDN plug-in and want to switch to another:

Change the networkPluginName parameter on all masters and nodes in their configuration files.

Restart the atomic-openshift-master service on masters and the atomic-openshift-node service on nodes.

If you are switching from an OpenShift Container Platform SDN plug-in to a third-party plug-in, then clean up OpenShift Container Platform SDN-specific artifacts:

$ oc delete clusternetwork --all
$ oc delete hostsubnets --all
$ oc delete netnamespaces --all

When switching from the ovs-subnet to the ovs-multitenant OpenShift Container Platform SDN plug-in, all the existing projects in the cluster will be fully isolated (assigned unique VNIDs). Cluster administrators can choose to modify the project networks using the administrator CLI.

Check VNIDs by running:

$ oc get netnamespace

External Access to the Cluster Network

If a host that is external to OpenShift Container Platform requires access to the cluster network, you have two options:

Configure the host as an OpenShift Container Platform node but mark it unschedulable so that the master does not schedule containers on it.

Create a tunnel between your host and a host that is on the cluster network.

Both options are presented as part of a practical use-case in the documentation for configuring routing from an edge load-balancer to containers within OpenShift Container Platform SDN.

Chapter 16. Configuring for AWS

Overview

OpenShift Container Platform can be configured to access an AWS EC2 infrastructure, including using AWS volumes as persistent storage for application data. After AWS is configured properly, some additional configurations will need to be completed on the OpenShift Container Platform hosts.

Configuring AWS Variables

To set the required AWS variables, create a /etc/aws/aws.conf file with the following contents on all of your OpenShift Container Platform hosts, both masters and nodes:

[Global]
Zone = us-east-1c

This is the Availability Zone of your AWS Instance and where your EBS Volume resides; this information is obtained from the AWS Managment Console.

Configuring OpenShift Container Platform Masters for AWS

You can set the AWS configuration on your OpenShift Container Platform master hosts in two ways:

using Ansible and the advanced installation tool

manually, by modifying the master-config.yaml file

Configuring OpenShift Container Platform for AWS with Ansible

During advanced installations, AWS can be configured using the openshift_cloudprovider_aws_access_key, openshift_cloudprovider_aws_secret_key, and openshift_cloudprovider_kind parameters, which are configurable in the inventory file.

Example 16.1. Example AWS Configuration with Ansible

# Cloud Provider Configuration
#
# Note: You may make use of environment variables rather than store
# sensitive configuration within the ansible inventory.
# For example:
#openshift_cloudprovider_aws_access_key="{{ lookup('env','AWS_ACCESS_KEY_ID') }}"
#openshift_cloudprovider_aws_secret_key="{{ lookup('env','AWS_SECRET_ACCESS_KEY') }}"
#
# AWS
#openshift_cloudprovider_kind=aws
# Note: IAM profiles may be used instead of storing API credentials on disk.
#openshift_cloudprovider_aws_access_key=aws_access_key_id
#openshift_cloudprovider_aws_secret_key=aws_secret_access_key

Note

When Ansible configures AWS, the following files are created for you:

/etc/aws/aws.conf

/etc/origin/master/master-config.yaml

/etc/origin/node/node-config.yaml

/etc/sysconfig/atomic-openshift-master

/etc/sysconfig/atomic-openshift-node

Manually Configuring OpenShift Container Platform Masters for AWS

Edit or create the master configuration file on all masters (/etc/origin/master/master-config.yaml by default) and update the contents of the apiServerArguments and controllerArguments sections:

kubernetesMasterConfig:
  ...
  apiServerArguments:
    cloud-provider:
      - "aws"
    cloud-config:
      - "/etc/aws/aws.conf"
  controllerArguments:
    cloud-provider:
      - "aws"
    cloud-config:
      - "/etc/aws/aws.conf"

Important

When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, aws.conf should be in /etc/origin/ instead of /etc/.

Manually Configuring OpenShift Container Platform Nodes for AWS

Edit or create the node configuration file on all nodes (/etc/origin/node/node-config.yaml by default) and update the contents of the kubeletArguments section:

kubeletArguments:
  cloud-provider:
    - "aws"
  cloud-config:
    - "/etc/aws/aws.conf"

Important

When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, aws.conf should be in /etc/origin/ instead of /etc/.

Setting Key Value Access Pairs

Make sure the following environment variables are set in the /etc/sysconfig/atomic-openshift-master file on masters and the /etc/sysconfig/atomic-openshift-node file on nodes:

AWS_ACCESS_KEY_ID=<key_ID>
AWS_SECRET_ACCESS_KEY=<secret_key>

Note

Access keys are obtained when setting up your AWS IAM user.

Applying Configuration Changes

Start or restart OpenShift Container Platform services on all master and node hosts to apply your configuration changes:

# systemctl restart atomic-openshift-master
# systemctl restart atomic-openshift-node

Switching from not using a cloud provider to using a cloud provider produces an error message. Adding the cloud provider tries to delete the node because the node switches from using the hostname as the externalID (which would have been the case when no cloud provider was being used) to using the AWS instance-id (which is what the AWS cloud provider specifies). To resolve this issue:

Log in to the CLI as a cluster administrator.

Delete the nodes:

$ oc delete node <node_name>

On each node host, restart the atomic-openshift-node service.

Add back any labels on each node that you previously had.

Chapter 17. Configuring for OpenStack

Overview

When deployed on OpenStack, OpenShift Container Platform can be configured to access OpenStack infrastructure, including using OpenStack Cinder volumes as persistent storage for application data.

Configuring OpenStack Variables

To set the required OpenStack variables, create a /etc/cloud.conf file with the following contents on all of your OpenShift Container Platform hosts, both masters and nodes:

[Global]
auth-url = <OS_AUTH_URL>
username = <OS_USERNAME>
password = <password>
tenant-id = <OS_TENANT_ID>
region = <OS_REGION_NAME>

[LoadBalancer]
subnet-id = <UUID of the load balancer subnet>

Consult your OpenStack administrators for values of the OS_ variables, which are commonly used in OpenStack configuration.

Configuring OpenShift Container Platform Masters for OpenStack

You can set an OpenStack configuration on your OpenShift Container Platform master and node hosts in two different ways:

Using Ansible and the advanced installation tool

Manually, by modifying the master-config.yaml and node-config.yaml files.

Configuring OpenShift Container Platform for OpenStack with Ansible

During advanced installations, OpenStack can be configured using the following parameters, which are configurable in the inventory file:

openshift_cloudprovider_kind

openshift_cloudprovider_openstack_auth_url

openshift_cloudprovider_openstack_username

openshift_cloudprovider_openstack_password

openshift_cloudprovider_openstack_tenant_id

openshift_cloudprovider_openstack_tenant_name

openshift_cloudprovider_openstack_region

openshift_cloudprovider_openstack_lb_subnet_id

Example 17.1. Example OpenStack Configuration with Ansible

# Cloud Provider Configuration
#
# Note: You may make use of environment variables rather than store
# sensitive configuration within the ansible inventory.
# For example:
#openshift_cloudprovider_openstack_username="{{ lookup('env','USERNAME') }}"
#openshift_cloudprovider_openstack_password="{{ lookup('env','PASSWORD') }}"
#
# Openstack
#openshift_cloudprovider_kind=openstack
#openshift_cloudprovider_openstack_auth_url=http://openstack.example.com:35357/v2.0/
#openshift_cloudprovider_openstack_username=username
#openshift_cloudprovider_openstack_password=password
#openshift_cloudprovider_openstack_tenant_id=tenant_id
#openshift_cloudprovider_openstack_tenant_name=tenant_name
#openshift_cloudprovider_openstack_region=region
#openshift_cloudprovider_openstack_lb_subnet_id=subnet_id

Manually Configuring OpenShift Container Platform Masters for OpenStack

Edit or create the master configuration file on all masters (/etc/origin/master/master-config.yaml by default) and update the contents of the apiServerArguments and controllerArguments sections:

kubernetesMasterConfig:
  ...
  apiServerArguments:
    cloud-provider:
      - "openstack"
    cloud-config:
      - "/etc/cloud.conf"
  controllerArguments:
    cloud-provider:
      - "openstack"
    cloud-config:
      - "/etc/cloud.conf"

Important

When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, cloud.conf should be in /etc/origin/ instead of /etc/.

Manually Configuring OpenShift Container Platform Nodes for OpenStack

Edit or create the node configuration file on all nodes (/etc/origin/node/node-config.yaml by default) and update the contents of the kubeletArguments and nodeName sections:

nodeName:
  <instance_name>

kubeletArguments:
  cloud-provider:
    - "openstack"
  cloud-config:
    - "/etc/cloud.conf"

Name of the OpenStack instance where the node runs (i.e., name of the virtual machine)

Important

When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, cloud.conf should be in /etc/origin/ instead of /etc/.

Chapter 18. Configuring for GCE

Overview

OpenShift Container Platform can be configured to access an GCE infrastructure, including using GCE volumes as persistent storage for application data. After GCE is configured properly, some additional configurations will need to be completed on the OpenShift Container Platform hosts.

Configuring Masters

Edit or create the master configuration file on all masters (/etc/origin/master/master-config.yaml by default) and update the contents of the apiServerArguments and controllerArguments sections:

kubernetesMasterConfig:
  ...
  apiServerArguments:
    cloud-provider:
      - "gce"
  controllerArguments:
    cloud-provider:
      - "gce"

Important

When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, master-config.yaml should be in /etc/origin/master instead of /etc/.

Configuring Nodes

Edit or create the node configuration file on all nodes (/etc/origin/node/node-config.yaml by default) and update the contents of the kubeletArguments section:

kubeletArguments:
  cloud-provider:
    - "gce"

Important

When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, node-config.yaml should be in /etc/origin/node instead of /etc/.

Then, start or restart the OpenShift Container Platform services on the master and all nodes.

Chapter 19. Configuring Persistent Storage

Overview

The Kubernetes persistent volume framework allows you to provision an OpenShift Container Platform cluster with persistent storage using networked storage available in your environment. This can be done after completing the initial OpenShift Container Platform installation depending on your application needs, giving users a way to request those resources without having any knowledge of the underlying infrastructure.

These topics show how to configure persistent volumes in OpenShift Container Platform using the following supported volume plug-ins:

NFS

GlusterFS

OpenStack Cinder

Ceph RBD

AWS Elastic Block Store (EBS)

GCE Persistent Disk

iSCSI

Fibre Channel

Selector-Label Volume Binding

Persistent Storage Using NFS

Overview

OpenShift Container Platform clusters can be provisioned with persistent storage using NFS. Persistent volumes (PVs) and persistent volume claims (PVCs) provide a convenient method for sharing a volume across a project. While the NFS-specific information contained in a PV definition could also be defined directly in a pod definition, doing so does not create the volume as a distinct cluster resource, making the volume more susceptible to conflicts.

This topic covers the specifics of using the NFS persistent storage type. Some familiarity with OpenShift Container Platform and NFS is beneficial. See the Persistent Storage concept topic for details on the OpenShift Container Platform persistent volume (PV) framework in general.

Provisioning

Storage must exist in the underlying infrastructure before it can be mounted as a volume in OpenShift Container Platform. To provision NFS volumes, a list of NFS servers and export paths are all that is required.

You must first create an object definition for the PV:

Example 19.1. PV Object Definition Using NFS

apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv0001
spec:
  capacity:
    storage: 5Gi
  accessModes:
  - ReadWriteOnce
  nfs:
    path: /tmp
    server: 172.17.0.2
  persistentVolumeReclaimPolicy: Recycle

The name of the volume. This is the PV identity in various oc <command> pod commands.

The amount of storage allocated to this volume.

Though this appears to be related to controlling access to the volume, it is actually used similarly to labels and used to match a PVC to a PV. Currently, no access rules are enforced based on the accessModes.

The volume type being used, in this case the nfs plug-in.

The path that is exported by the NFS server.

The host name or IP address of the NFS server.

The reclaim policy for the PV. This defines what happens to a volume when released from its claim. Valid options are Retain (default) and Recycle. See Reclaiming Resources.

Note

Each NFS volume must be mountable by all schedulable nodes in the cluster.

Save the definition to a file, for example nfs-pv.yaml, and create the PV:

$ oc create -f nfs-pv.yaml
persistentvolume "pv0001" created

Verify that the PV was created:

# oc get pv
NAME                     LABELS    CAPACITY     ACCESSMODES   STATUS      CLAIM     REASON    AGE
pv0001                   <none>    5368709120   RWO           Available                       31s

The next step can be to create a persistent volume claim (PVC) which will bind to the new PV:

Example 19.2. PVC Object Definition

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: nfs-claim1
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi

As mentioned above for PVs, the accessModes do not enforce security, but rather act as labels to match a PV to a PVC.

This claim will look for PVs offering 1Gi or greater capacity.

Save the definition to a file, for example nfs-claim.yaml, and create the PVC:

# oc create -f nfs-claim.yaml

Enforcing Disk Quotas

You can use disk partitions to enforce disk quotas and size constraints. Each partition can be its own export. Each export is one PV. OpenShift Container Platform enforces unique names for PVs, but the uniqueness of the NFS volume’s server and path is up to the administrator.

Enforcing quotas in this way allows the developer to request persistent storage by a specific amount (for example, 10Gi) and be matched with a corresponding volume of equal or greater capacity.

NFS Volume Security

This section covers NFS volume security, including matching permissions and SELinux considerations. The reader is expected to understand the basics of POSIX permissions, process UIDs, supplemental groups, and SELinux.

Note

See the full Volume Security topic before implementing NFS volumes.

Developers request NFS storage by referencing, in the volumes section of their pod definition, either a PVC by name or the NFS volume plug-in directly.

The /etc/exports file on the NFS server contains the accessible NFS directories. The target NFS directory has POSIX owner and group IDs. The OpenShift Container Platform NFS plug-in mounts the container’s NFS directory with the same POSIX ownership and permissions found on the exported NFS directory. However, the container is not run with its effective UID equal to the owner of the NFS mount, which is the desired behavior.

As an example, if the target NFS directory appears on the NFS server as:

# ls -lZ /opt/nfs -d
drwxrws---. nfsnobody 5555 unconfined_u:object_r:usr_t:s0   /opt/nfs

# id nfsnobody
uid=65534(nfsnobody) gid=65534(nfsnobody) groups=65534(nfsnobody)

Then the container must match SELinux labels, and either run with a UID of 65534 (nfsnobody owner) or with 5555 in its supplemental groups in order to access the directory.

Note

The owner ID of 65534 is used as an example. Even though NFS’s root_squash maps root (0) to nfsnobody (65534), NFS exports can have arbitrary owner IDs. Owner 65534 is not required for NFS exports.

Group IDs

The recommended way to handle NFS access (assuming it is not an option to change permissions on the NFS export) is to use supplemental groups. Supplemental groups in OpenShift Container Platform are used for shared storage, of which NFS is an example. In contrast, block storage, such as Ceph RBD or iSCSI, use the fsGroup SCC strategy and the fsGroup value in the pod’s securityContext.

Note

It is generally preferable to use supplemental group IDs to gain access to persistent storage versus using user IDs. Supplemental groups are covered further in the full Volume Security topic.

Because the group ID on the example target NFS directory shown above is 5555, the pod can define that group ID using supplementalGroups under the pod-level securityContext definition. For example:

spec:
  containers:
    - name:
    ...
  securityContext:
    supplementalGroups: [5555]

securityContext must be defined at the pod level, not under a specific container.

An array of GIDs defined for the pod. In this case, there is one element in the array; additional GIDs would be comma-separated.

Assuming there are no custom SCCs that might satisfy the pod’s requirements, the pod will likely match the restricted SCC. This SCC has the supplementalGroups strategy set to RunAsAny, meaning that any supplied group ID will be accepted without range checking.

As a result, the above pod will pass admissions and will be launched. However, if group ID range checking is desired, a custom SCC, as described in pod security and custom SCCs, is the preferred solution. A custom SCC can be created such that minimum and maximum group IDs are defined, group ID range checking is enforced, and a group ID of 5555 is allowed.

User IDs

User IDs can be defined in the container image or in the pod definition. The full Volume Security topic covers controlling storage access based on user IDs, and should be read prior to setting up NFS persistent storage.

Note

It is generally preferable to use supplemental group IDs to gain access to persistent storage versus using user IDs.

In the example target NFS directory shown above, the container needs its UID set to 65534 (ignoring group IDs for the moment), so the following can be added to the pod definition:

spec:
  containers:
  - name:
  ...
    securityContext:
      runAsUser: 65534

Pods contain a securtityContext specific to each container (shown here) and a pod-level securityContext which applies to all containers defined in the pod.

65534 is the nfsnobody user.

Assuming the default project and the restricted SCC, the pod’s requested user ID of 65534 will, unfortunately, not be allowed, and therefore the pod will fail. The pod fails because of the following:

It requests 65534 as its user ID.

All SCCs available to the pod are examined to see which SCC will allow a user ID of 65534 (actually, all policies of the SCCs are checked but the focus here is on user ID).

Because all available SCCs use MustRunAsRange for their runAsUser strategy, UID range checking is required.

65534 is not included in the SCC or project’s user ID range.

It is generally considered a good practice not to modify the predefined SCCs. The preferred way to fix this situation is to create a custom SCC, as described in the full Volume Security topic. A custom SCC can be created such that minimum and maximum user IDs are defined, UID range checking is still enforced, and the UID of 65534 will be allowed.

SELinux

Note

See the full Volume Security topic for information on controlling storage access in conjunction with using SELinux.

By default, SELinux does not allow writing from a pod to a remote NFS server. The NFS volume mounts correctly, but is read-only.

To enable writing to NFS volumes with SELinux enforcing on each node, run:

# setsebool -P virt_use_nfs 1
# setsebool -P virt_sandbox_use_nfs 1

The -P option above makes the bool persistent between reboots.

The virt_use_nfs boolean is defined by the docker-selinux package. If an error is seen indicating that this bool is not defined, ensure this package has been installed.

Export Settings

In order to enable arbitrary container users to read and write the volume, each exported volume on the NFS server should conform to the following conditions:

Each export must be:

/<example_fs> *(rw,root_squash,no_wdelay)

The no_wdelay option prevents the server from delaying writes, which greatly improves read-after-write consistency.

The firewall must be configured to allow traffic to the mount point. For NFSv4, the default port is 2049 (nfs). For NFSv3, there are three ports to configure: 2049 (nfs), 20048 (mountd), and 111 (portmapper).

NFSv4

# iptables -I INPUT 1 -p tcp --dport 2049 -j ACCEPT

NFSv3

# iptables -I INPUT 1 -p tcp --dport 2049 -j ACCEPT
# iptables -I INPUT 1 -p tcp --dport 20048 -j ACCEPT
# iptables -I INPUT 1 -p tcp --dport 111 -j ACCEPT

The NFS export and directory must be set up so that it is accessible by the target pods. Either set the export to be owned by the container’s primary UID, or supply the pod group access using supplementalGroups, as shown in Group IDs above. See the full Volume Security topic for additional pod security information as well.

Reclaiming Resources

NFS implements the OpenShift Container Platform Recyclable plug-in interface. Automatic processes handle reclamation tasks based on policies set on each persistent volume.

By default, persistent volumes are set to Retain. NFS volumes which are set to Recycle are scrubbed (i.e., rm -rf is run on the volume) after being released from their claim (i.e, after the user’s PersistentVolumeClaim bound to the volume is deleted). Once recycled, the NFS volume can be bound to a new claim.

Automation

Clusters can be provisioned with persistent storage using NFS in the following ways:

Enforce storage quotas using disk partitions.

Enforce security by restricting volumes to the project that has a claim to them.

Configure reclamation of discarded resources for each PV.

They are many ways that you can use scripts to automate the above tasks. You can use an example Ansible playbook to help you get started.

Additional Configuration and Troubleshooting

Depending on what version of NFS is being used and how it is configured, there may be additional configuration steps needed for proper export and security mapping. The following are some that may apply:

NFSv4 mount incorrectly shows all files with ownership of nobody:nobody

Could be attributed to the ID mapping settings (/etc/idmapd.conf) on your NFS

See this Red Hat Solution.

Disabling ID mapping on NFSv4

On both the NFS client and server, run:

# echo 'Y' > /sys/module/nfsd/parameters/nfs4_disable_idmapping

Persistent Storage Using GlusterFS

Overview

You can configure your OpenShift Container Platform cluster to use Red Hat Gluster Storage as persistent storage for containerized applications. There are two deployment solutions available when using Red Hat Gluster Storage, using either a containerized or dedicated storage cluster. This topic focuses mainly on the the persistent volume plug-in solution using a dedicated Red Hat Gluster Storage cluster.

Containerized Red Hat Gluster Storage

Starting with the Red Hat Gluster Storage 3.1 update 3 release, you can deploy containerized Red Hat Gluster Storage directly on OpenShift Container Platform. Containerized Red Hat Gluster Storage converged with OpenShift Container Platform addresses the use case where containerized applications require both shared file storage and the flexibility of a converged infrastructure with compute and storage instances being scheduled and run from the same set of hardware.

Figure 19.1. Architecture - Red Hat Gluster Storage Container Converged with OpenShift

Step-by-step instructions for this containerized solution are provided separately in the following documentation:

Deployment Guide for Containerized Red Hat Gluster Storage

Dedicated Storage Cluster

If you have a dedicated Red Hat Gluster Storage cluster available in your environment, you can configure OpenShift Container Platform’s Gluster volume plug-in. The dedicated storage cluster delivers persistent Red Hat Gluster Storage file storage for containerized applications over the network. The applications access storage served out from the storage clusters through common storage protocols.

Figure 19.2. Architecture - Dedicated Red Hat Gluster Storage Cluster Using the OpenShift Container Platform Volume Plug-in

This solution is a conventional deployment where containerized compute applications run on an OpenShift Container Platform cluster. The remaining sections in this topic provide the step-by-step instructions for the dedicated Red Hat Gluster Storage solution.

This topic presumes some familiarity with OpenShift Container Platform and GlusterFS; see the Red Hat Gluster Storage 3 Administration Guide for more on GlusterFS. See the Persistent Storage topic for details on the OpenShift Container Platform PV framework in general.

Important

High-availability of storage in the infrastructure is left to the underlying storage provider.

Support Requirements

The following requirements must be met to create a supported integration of Red Hat Gluster Storage and OpenShift Container Platform.

Supported Operating Systems

The following table lists the supported versions of OpenShift Container Platform with Red Hat Gluster Storage Server.

Red Hat Gluster Storage
OpenShift Container Platform

3.1.3

3.1 or later

Environment Requirements

The environment requirements for OpenShift Container Platform and Red Hat Gluster Storage are described in this section.

Red Hat Gluster Storage

All installations of Red Hat Gluster Storage must have valid subscriptions to Red Hat Network channels and Subscription Management repositories.

Red Hat Gluster Storage installations must adhere to the requirements laid out in the Red Hat Gluster Storage Installation Guide.

Red Hat Gluster Storage installations must be completely up to date with the latest patches and upgrades. Refer to the Red Hat Gluster Storage 3.1 Installation Guide to upgrade to the latest version.

The versions of OpenShift Container Platform and Red Hat Gluster Storage integrated must be compatible, according to the information in Supported Operating Systems.

A fully-qualified domain name (FQDN) must be set for each hypervisor and Red Hat Gluster Storage server node. Ensure that correct DNS records exist, and that the FQDN is resolvable via both forward and reverse DNS lookup.

Red Hat OpenShift Enterprise

All installations of OpenShift Container Platform must have valid subscriptions to Red Hat Network channels and Subscription Management repositories.

OpenShift Container Platform installations must adhere to the requirements laid out in the Installation and Configuration documentation.

The OpenShift Container Platform cluster must be up and running.

A user with cluster-admin permissions must be created.

All OpenShift Container Platform nodes on RHEL systems must have the glusterfs-fuse RPM installed, which should match the version of Red Hat Gluster Storage server running in the containers. For more information on installing glusterfs-fuse, see Native Client in the Red Hat Gluster Storage Administration Guide.

Provisioning

To provision GlusterFS volumes the following are required:

An existing storage device in your underlying infrastructure.

A distinct list of servers (IP addresses) in the Gluster cluster, to be defined as endpoints.

A service, to persist the endpoints (optional).

An existing Gluster volume to be referenced in the persistent volume object.

glusterfs-fuse installed on each schedulable OpenShift Container Platform node in your cluster:

# yum install glusterfs-fuse

Note

Persistent volumes (PVs) and persistent volume claims (PVCs) can share volumes across a single project. While the GlusterFS-specific information contained in a PV definition could also be defined directly in a pod definition, doing so does not create the volume as a distinct cluster resource, making the volume more susceptible to conflicts.

Creating Gluster Endpoints

An endpoints definition defines the GlusterFS cluster as EndPoints and includes the IP addresses of your Gluster servers. The port value can be any numeric value within the accepted range of ports. Optionally, you can create a service that persists the endpoints.

Define the following service:

Example 19.3. Gluster Service Definition

apiVersion: v1
kind: Service
metadata:
  name: glusterfs-cluster
spec:
  ports:
  - port: 1

This name must be defined in the endpoints definition. If using a service, then the endpoints name must match the service name.

Save the service definition to a file, for example gluster-service.yaml, then create the service:

$ oc create -f gluster-service.yaml

Verify that the service was created:

# oc get services
NAME                       CLUSTER_IP       EXTERNAL_IP   PORT(S)    SELECTOR        AGE
glusterfs-cluster          172.30.205.34    <none>        1/TCP      <none>          44s

Define the Gluster endpoints:

Example 19.4. Gluster Endpoints Definition

apiVersion: v1
kind: Endpoints
metadata:
  name: glusterfs-cluster
subsets:
  - addresses:
      - ip: 192.168.122.221
    ports:
      - port: 1
  - addresses:
      - ip: 192.168.122.222
    ports:
      - port: 1

This name must match the service name from step 1.

The ip values must be the actual IP addresses of a Gluster server, not fully-qualified host names.

The port number is ignored.

Save the endpoints definition to a file, for example gluster-endpoints.yaml, then create the endpoints:

$ oc create -f gluster-endpoints.yaml
endpoints "glusterfs-cluster" created

Verify that the endpoints were created:

$ oc get endpoints
NAME                ENDPOINTS                             AGE
docker-registry     10.1.0.3:5000                         4h
glusterfs-cluster   192.168.122.221:1,192.168.122.222:1   11s
kubernetes          172.16.35.3:8443                      4d

Creating the Persistent Volume

Note

GlusterFS does not support the 'Recycle' recycling policy.

Next, define the PV in an object definition before creating it in OpenShift Container Platform:

Example 19.5. Persistent Volume Object Definition Using GlusterFS

apiVersion: v1
kind: PersistentVolume
metadata:
  name: gluster-default-volume
spec:
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteMany
  glusterfs:
    endpoints: glusterfs-cluster
    path: myVol1
    readOnly: false
  persistentVolumeReclaimPolicy: Retain

The name of the volume. This is how it is identified via persistent volume claims or from pods.

The amount of storage allocated to this volume.

accessModes are used as labels to match a PV and a PVC. They currently do not define any form of access control.

The volume type being used, in this case the glusterfs plug-in.

The endpoints name that defines the Gluster cluster created in Creating Gluster Endpoints.

The Gluster volume that will be accessed, as shown in the gluster volume status command.

The Recycle policy is currently not supported with glusterfs

Note

Endpoints are name-spaced. Each project accessing the Gluster volume needs its own endpoints.

Save the definition to a file, for example gluster-pv.yaml, and create the persistent volume:

# oc create -f gluster-pv.yaml

Verify that the persistent volume was created:

# oc get pv
NAME                     LABELS    CAPACITY     ACCESSMODES   STATUS      CLAIM     REASON    AGE
gluster-default-volume   <none>    2147483648   RWX           Available                       2s

Creating the Persistent Volume Claim

Developers request GlusterFS storage by referencing either a PVC or the Gluster volume plug-in directly in the volumes section of a pod spec. A PVC exists only in the user’s project and can only be referenced by pods within that project. Any attempt to access a PV across a project causes the pod to fail.

Create a PVC that will bind to the new PV:

Example 19.6. PVC Object Definition

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: gluster-claim
spec:
  accessModes:
  - ReadWriteMany
  resources:
     requests:
       storage: 1Gi

accessModes do not enforce security, but rather act as labels to match a PV to a PVC.

This claim will look for PVs offering 1Gi or greater capacity.

Save the definition to a file, for example gluster-claim.yaml, and create the PVC:

# oc create -f gluster-claim.yaml

Note

PVs and PVCs make sharing a volume across a project simpler. The gluster-specific information contained in the PV definition can also be defined directly in a pod specification.

Gluster Volume Security

This section covers Gluster volume security, including matching permissions and SELinux considerations. Understanding the basics of POSIX permissions, process UIDs, supplemental groups, and SELinux is presumed.

Note

See the full Volume Security topic before implementing Gluster volumes.

As an example, assume that the target Gluster volume, HadoopVol is mounted under /mnt/glusterfs/, with the following POSIX permissions and SELinux labels:

# ls -lZ /mnt/glusterfs/
drwxrwx---. yarn hadoop system_u:object_r:fusefs_t:s0    HadoopVol

# id yarn
uid=592(yarn) gid=590(hadoop) groups=590(hadoop)

In order to access the HadoopVol volume, containers must match the SELinux label, and run with a UID of 592 or 590 in their supplemental groups. The OpenShift Container Platform GlusterFS plug-in mounts the volume in the container with the same POSIX ownership and permissions found on the target gluster mount, namely the owner will be 592 and group ID will be 590. However, the container is not run with its effective UID equal to 592, nor with its GID equal to 590, which is the desired behavior. Instead, a container’s UID and supplemental groups are determined by Security Context Constraints (SCCs) and the project defaults.

Group IDs

Configure Gluster volume access by using supplemental groups, assuming it is not an option to change permissions on the Gluster mount. Supplemental groups in OpenShift Container Platform are used for shared storage, such as GlusterFS. In contrast, block storage, such as Ceph RBD or iSCSI, use the fsGroup SCC strategy and the fsGroup value in the pod’s securityContext.

Note

Use supplemental group IDs instead of user IDs to gain access to persistent storage. Supplemental groups are covered further in the full Volume Security topic.

The group ID on the target Gluster mount example above is 590. Therefore, a pod can define that group ID using supplementalGroups under the pod-level securityContext definition. For example:

spec:
  containers:
    - name:
    ...
  securityContext:
    supplementalGroups: [590]

securityContext must be defined at the pod level, not under a specific container.

An array of GIDs defined at the pod level.

Assuming there are no custom SCCs that satisfy the pod’s requirements, the pod matches the restricted SCC. This SCC has the supplementalGroups strategy set to RunAsAny, meaning that any supplied group IDs are accepted without range checking.

As a result, the above pod will pass admissions and can be launched. However, if group ID range checking is desired, use a custom SCC, as described in pod security and custom SCCs. A custom SCC can be created to define minimum and maximum group IDs, enforce group ID range checking, and allow a group ID of 590.

User IDs

User IDs can be defined in the container image or in the pod definition. The full Volume Security topic covers controlling storage access based on user IDs, and should be read prior to setting up NFS persistent storage.

Note

Use supplemental group IDs instead of user IDs to gain access to persistent storage.

In the target Gluster mount example above, the container needs a UID set to 592, so the following can be added to the pod definition:

spec:
  containers:
  - name:
  ...
    securityContext:
      runAsUser: 592

Pods contain a securtityContext specific to each container and a pod-level securityContext, which applies to all containers defined in the pod.

The UID defined on the Gluster mount.

With the default project and the restricted SCC, a pod’s requested user ID of 592 will not be allowed, and the pod will fail. This is because:

The pod requests 592 as its user ID.

All SCCs available to the pod are examined to see which SCC will allow a user ID of 592.

Because all available SCCs use MustRunAsRange for their runAsUser strategy, UID range checking is required.

592 is not included in the SCC or project’s user ID range.

Do not modify the predefined SCCs. Insead, create a custom SCC so that minimum and maximum user IDs are defined, UID range checking is still enforced, and the UID of 592 will be allowed.

SELinux

Note

See the full Volume Security topic for information on controlling storage access in conjunction with using SELinux.

By default, SELinux does not allow writing from a pod to a remote Gluster server.

To enable writing to GlusterFS volumes with SELinux enforcing on each node, run:

$ sudo setsebool -P virt_sandbox_use_fusefs on

Note

The virt_sandbox_use_fusefs boolean is defined by the docker-selinux package. If you get an error saying it is not defined, please ensure that this package is installed.

The -P option makes the bool persistent between reboots.

Persistent Storage Using OpenStack Cinder

Overview

You can provision your OpenShift Container Platform cluster with persistent storage using OpenStack Cinder. Some familiarity with Kubernetes and OpenStack is assumed.

Important

Before creating persistent volumes using Cinder, OpenShift Container Platform must first be properly configured for OpenStack.

The Kubernetes persistent volume framework allows administrators to provision a cluster with persistent storage and gives users a way to request those resources without having any knowledge of the underlying infrastructure. OpenStack Cinder volumes can be provisioned dynamically. Persistent volumes are not bound to a single project or namespace; they can be shared across the OpenShift Container Platform cluster. Persistent volume claims, however, are specific to a project or namespace and can be requested by users.

For a detailed example, see the guide for WordPress and MySQL using persistent volumes.

Important

High-availability of storage in the infrastructure is left to the underlying storage provider.

Provisioning

Storage must exist in the underlying infrastructure before it can be mounted as a volume in OpenShift Container Platform. After ensuring OpenShift Container Platform is configured for OpenStack, all that is required for Cinder is a Cinder volume ID and the PersistentVolume API.

Creating the Persistent Volume

Note

Cinder does not support the 'Recycle' recycling policy.

You must define your persistent volume in an object definition before creating it in OpenShift Container Platform:

Example 19.7. Persistent Volume Object Definition Using Cinder

apiVersion: "v1"
kind: "PersistentVolume"
metadata:
  name: "pv0001"
spec:
  capacity:
    storage: "5Gi"
  accessModes:
    - "ReadWriteOnce"
  cinder:
    fsType: "ext3"
    volumeID: "f37a03aa-6212-4c62-a805-9ce139fab180"

The name of the volume. This will be how it is identified via persistent volume claims or from pods.

The amount of storage allocated to this volume.

This defines the volume type being used, in this case the cinder plug-in.

File system type to mount.

This is the Cinder volume that will be used.

Important

Changing the value of the fstype parameter after the volume has been formatted and provisioned can result in data loss and pod failure.

Save your definition to a file, for example cinder-pv.yaml, and create the persistent volume:

# oc create -f cinder-pv.yaml
persistentvolume "pv0001" created

Verify that the persistent volume was created:

# oc get pv
NAME      LABELS    CAPACITY   ACCESSMODES   STATUS      CLAIM     REASON    AGE
pv0001    <none>    5Gi        RWO           Available                       2s

Users can then request storage using persistent volume claims, which can now utilize your new persistent volume.

Important

Persistent volume claims only exist in the user’s namespace and can only be referenced by a pod within that same namespace. Any attempt to access a persistent volume from a different namespace causes the pod to fail.

Volume Format

Before OpenShift Container Platform mounts the volume and passes it to a container, it checks that it contains a file system as specified by the fsType parameter in the persistent volume definition. If the device is not formatted with the file system, all data from the device is erased and the device is automatically formatted with the given file system.

This allows using unformatted Cinder volumes as persistent volumes, because OpenShift Container Platform formats them before the first use.

Persistent Storage Using Ceph Rados Block Device (RBD)

Overview

OpenShift Container Platform clusters can be provisioned with persistent storage using Ceph RBD.

Persistent volumes (PVs) and persistent volume claims (PVCs) can share volumes across a single project. While the Ceph RBD-specific information contained in a PV definition could also be defined directly in a pod definition, doing so does not create the volume as a distinct cluster resource, making the volume more susceptible to conflicts.

This topic presumes some familiarity with OpenShift Container Platform and Ceph RBD. See the Persistent Storage concept topic for details on the OpenShift Container Platform persistent volume (PV) framework in general.

Note

Project and namespace are used interchangeably throughout this document. See Projects and Users for details on the relationship.

Important

High-availability of storage in the infrastructure is left to the underlying storage provider.

Provisioning

To provision Ceph volumes, the following are required:

An existing storage device in your underlying infrastructure.

The Ceph key to be used in an OpenShift Container Platform secret object.

The Ceph image name.

The file system type on top of the block storage (e.g., ext4).

ceph-common installed on each schedulable OpenShift Container Platform node in your cluster:

# yum install ceph-common

Creating the Ceph Secret

Define the authorization key in a secret configuration, which is then converted to base64 for use by OpenShift Container Platform.

Note

In order to use Ceph storage to back a persistent volume, the secret must be created in the same project as the PVC and pod. The secret cannot simply be in the default project.

Run ceph auth get-key on a Ceph MON node to display the key value for the client.admin user:

apiVersion: v1
kind: Secret
metadata:
  name: ceph-secret
data:
  key: QVFBOFF2SlZheUJQRVJBQWgvS2cwT1laQUhPQno3akZwekxxdGc9PQ==

Save the secret definition to a file, for example ceph-secret.yaml, then create the secret:

$ oc create -f ceph-secret.yaml

Verify that the secret was created:

# oc get secret ceph-secret
NAME          TYPE      DATA      AGE
ceph-secret   Opaque    1         23d

Creating the Persistent Volume

Note

Ceph RBD does not support the 'Recycle' recycling policy.

Developers request Ceph RBD storage by referencing either a PVC, or the Gluster volume plug-in directly in the volumes section of a pod specification. A PVC exists only in the user’s namespace and can be referenced only by pods within that same namespace. Any attempt to access a PV from a different namespace causes the pod to fail.

Define the PV in an object definition before creating it in OpenShift Container Platform:

Example 19.8. Persistent Volume Object Definition Using Ceph RBD

apiVersion: v1
kind: PersistentVolume
metadata:
  name: ceph-pv
spec:
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteOnce
  rbd:
    monitors:
      - 192.168.122.133:6789
    pool: rbd
    image: ceph-image
    user: admin
    secretRef:
      name: ceph-secret
    fsType: ext4
    readOnly: false
  persistentVolumeReclaimPolicy: Retain

The name of the PV that is referenced in pod definitions or displayed in various oc volume commands.

The amount of storage allocated to this volume.

accessModes are used as labels to match a PV and a PVC. They currently do not define any form of access control. All block storage is defined to be single user (non-shared storage).

The volume type being used, in this case the rbd plug-in.

An array of Ceph monitor IP addresses and ports.

The Ceph secret used to create a secure connection from OpenShift Container Platform to the Ceph server.

The file system type mounted on the Ceph RBD block device.

Important

Changing the value of the fstype parameter after the volume has been formatted and provisioned can result in data loss and pod failure.

Save your definition to a file, for example ceph-pv.yaml, and create the PV:

# oc create -f ceph-pv.yaml

Verify that the persistent volume was created:

# oc get pv
NAME                     LABELS    CAPACITY     ACCESSMODES   STATUS      CLAIM     REASON    AGE
ceph-pv                  <none>    2147483648   RWO           Available                       2s

Create a PVC that will bind to the new PV:

Example 19.9. PVC Object Definition

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: ceph-claim
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

The accessModes do not enforce access right, but instead act as labels to match a PV to a PVC.

This claim looks for PVs offering 2Gi or greater capacity.

Save the definition to a file, for example ceph-claim.yaml, and create the PVC:

# oc create -f ceph-claim.yaml

Ceph Volume Security

Note

See the full Volume Security topic before implementing Ceph RBD volumes.

A significant difference between shared volumes (NFS and GlusterFS) and block volumes (Ceph RBD, iSCSI, and most cloud storage), is that the user and group IDs defined in the pod definition or container image are applied to the target physical storage. This is referred to as managing ownership of the block device. For example, if the Ceph RBD mount has its owner set to 123 and its group ID set to 567, and if the pod defines its runAsUser set to 222 and its fsGroup to be 7777, then the Ceph RBD physical mount’s ownership will be changed to 222:7777.

Note

Even if the user and group IDs are not defined in the pod specification, the resulting pod may have defaults defined for these IDs based on its matching SCC, or its project. See the full Volume Security topic which covers storage aspects of SCCs and defaults in greater detail.

A pod defines the group ownership of a Ceph RBD volume using the fsGroup stanza under the pod’s securityContext definition:

spec:
  containers:
    - name:
    ...
  securityContext:
    fsGroup: 7777

The securityContext must be defined at the pod level, not under a specific container.

All containers in the pod will have the same fsGroup ID.

Persistent Storage Using AWS Elastic Block Store

Overview

OpenShift Container Platform supports AWS Elastic Block Store volumes (EBS). You can provision your OpenShift Container Platform cluster with persistent storage using AWS EC2. Some familiarity with Kubernetes and AWS is assumed.

Important

Before creating persistent volumes using AWS, OpenShift Container Platform must first be properly configured for AWS ElasticBlockStore.

The Kubernetes persistent volume framework allows administrators to provision a cluster with persistent storage and gives users a way to request those resources without having any knowledge of the underlying infrastructure. AWS Elastic Block Store volumes can be provisioned dynamically. Persistent volumes are not bound to a single project or namespace; they can be shared across the OpenShift Container Platform cluster. Persistent volume claims, however, are specific to a project or namespace and can be requested by users.

Important

High-availability of storage in the infrastructure is left to the underlying storage provider.

Provisioning

Storage must exist in the underlying infrastructure before it can be mounted as a volume in OpenShift Container Platform. After ensuring OpenShift is configured for AWS Elastic Block Store, all that is required for OpenShift and AWS is an AWS EBS volume ID and the PersistentVolume API.

Creating the Persistent Volume

Note

AWS does not support the 'Recycle' recycling policy.

You must define your persistent volume in an object definition before creating it in OpenShift Container Platform:

Example 19.10. Persistent Volume Object Definition Using AWS

apiVersion: "v1"
kind: "PersistentVolume"
metadata:
  name: "pv0001"
spec:
  capacity:
    storage: "5Gi"
  accessModes:
    - "ReadWriteOnce"
  awsElasticBlockStore:
    fsType: "ext4"
    volumeID: "vol-f37a03aa"

The name of the volume. This will be how it is identified via persistent volume claims or from pods.

The amount of storage allocated to this volume.

This defines the volume type being used, in this case the awsElasticBlockStore plug-in.

File system type to mount.

This is the AWS volume that will be used.

Important

Changing the value of the fstype parameter after the volume has been formatted and provisioned can result in data loss and pod failure.

Save your definition to a file, for example aws-pv.yaml, and create the persistent volume:

# oc create -f aws-pv.yaml
persistentvolume "pv0001" created

Verify that the persistent volume was created:

# oc get pv
NAME      LABELS    CAPACITY   ACCESSMODES   STATUS      CLAIM     REASON    AGE
pv0001    <none>    5Gi        RWO           Available                       2s

Users can then request storage using persistent volume claims, which can now utilize your new persistent volume.

Important

Persistent volume claims only exist in the user’s namespace and can only be referenced by a pod within that same namespace. Any attempt to access a persistent volume from a different namespace causes the pod to fail.

Volume Format

Before OpenShift Container Platform mounts the volume and passes it to a container, it checks that it contains a file system as specified by the fsType parameter in the persistent volume definition. If the device is not formatted with the file system, all data from the device is erased and the device is automatically formatted with the given file system.

This allows using unformatted AWS volumes as persistent volumes, because OpenShift Container Platform formats them before the first use.

Persistent Storage Using GCE Persistent Disk

Overview

OpenShift Container Platform supports GCE Persistent Disk volumes (gcePD). You can provision your OpenShift Container Platform cluster with persistent storage using GCE. Some familiarity with Kubernetes and GCE is assumed.

Important

Before creating persistent volumes using GCE, OpenShift Container Platform must first be properly configured for GCE Persistent Disk.

The Kubernetes persistent volume framework allows administrators to provision a cluster with persistent storage and gives users a way to request those resources without having any knowledge of the underlying infrastructure. GCE Persistent Disk volumes can be provisioned dynamically. Persistent volumes are not bound to a single project or namespace; they can be shared across the OpenShift Container Platform cluster. Persistent volume claims, however, are specific to a project or namespace and can be requested by users.

Important

High-availability of storage in the infrastructure is left to the underlying storage provider.

Provisioning

Storage must exist in the underlying infrastructure before it can be mounted as a volume in OpenShift Container Platform. After ensuring OpenShift Container Platform is configured for GCE PersistentDisk, all that is required for OpenShift Container Platform and GCE is an GCE Persistent Disk volume ID and the PersistentVolume API.

Creating the Persistent Volume

Note

GCE does not support the 'Recycle' recycling policy.

You must define your persistent volume in an object definition before creating it in OpenShift Container Platform:

Example 19.11. Persistent Volume Object Definition Using GCE

apiVersion: "v1"
kind: "PersistentVolume"
metadata:
  name: "pv0001"
spec:
  capacity:
    storage: "5Gi"
  accessModes:
    - "ReadWriteOnce"
  gcePersistentDisk:
    fsType: "ext4"
    pdName: "pd-disk-1"

The name of the volume. This will be how it is identified via persistent volume claims or from pods.

The amount of storage allocated to this volume.

This defines the volume type being used, in this case the gcePersistentDisk plug-in.

File system type to mount.

This is the GCE Persistent Disk volume that will be used.

Important

Changing the value of the fstype parameter after the volume has been formatted and provisioned can result in data loss and pod failure.

Save your definition to a file, for example gce-pv.yaml, and create the persistent volume:

# oc create -f gce-pv.yaml
persistentvolume "pv0001" created

Verify that the persistent volume was created:

# oc get pv
NAME      LABELS    CAPACITY   ACCESSMODES   STATUS      CLAIM     REASON    AGE
pv0001    <none>    5Gi        RWO           Available                       2s

Users can then request storage using persistent volume claims, which can now utilize your new persistent volume.

Important

Persistent volume claims only exist in the user’s namespace and can only be referenced by a pod within that same namespace. Any attempt to access a persistent volume from a different namespace causes the pod to fail.

Volume Format

Before OpenShift Container Platform mounts the volume and passes it to a container, it checks that it contains a file system as specified by the fsType parameter in the persistent volume definition. If the device is not formatted with the file system, all data from the device is erased and the device is automatically formatted with the given file system.

This allows using unformatted GCE volumes as persistent volumes, because OpenShift Container Platform formats them before the first use.

Multi-zone Configuration

In multi-zone configurations, if the volume being created does not exist in the master node’s zone, you must specify failure-domain.beta.kubernetes.io/region and failure-domain.beta.kubernetes.io/zone PV labels to match the zone where the GCE volume exists.

Example 19.12. Persistent Volume Object With Failure Domain

apiVersion: "v1"
kind: "PersistentVolume"
metadata:
  name: "pv0001"
  labels:
    failure-domain.beta.kubernetes.io/region: "us-central1"
    failure-domain.beta.kubernetes.io/zone: "us-central1-a"
spec:
  capacity:
    storage: "5Gi"
  accessModes:
    - "ReadWriteOnce"
  gcePersistentDisk:
    fsType: "ext4"
    pdName: "pd-disk-1"

The region in which the volume exists.

The zone in which the volume exists.

Persistent Storage Using iSCSI

Overview

You can provision your OpenShift Container Platform cluster with persistent storage using iSCSI. Some familiarity with Kubernetes and iSCSI is assumed.

The Kubernetes persistent volume framework allows administrators to provision a cluster with persistent storage and gives users a way to request those resources without having any knowledge of the underlying infrastructure.

Important

High-availability of storage in the infrastructure is left to the underlying storage provider.

Provisioning

Storage must exist in the underlying infrastructure before it can be mounted as a volume in OpenShift Container Platform. All that is required for iSCSI is iSCSI target portal, valid iSCSI IQN, valid LUN number, and filesystem type, and the PersistentVolume API.

Note

iSCSI does not support the 'Recycle' recycling policy.

Example 19.13. Persistent Volume Object Definition

apiVersion: v1
kind: PersistentVolume
metadata:
  name: iscsi-pv
spec:
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteOnce
  iscsi:
     targetPortal: 10.16.154.81
     iqn: iqn.2014-12.example.server:storage.target00
     lun: 0
     fsType: 'ext4'
     readOnly: false

Enforcing Disk Quotas

Use LUN partitions to enforce disk quotas and size constraints. Each LUN is one persistent volume. Kubernetes enforces unique names for persistent volumes.

Enforcing quotas in this way allows the end user to request persistent storage by a specific amount (e.g, 10Gi) and be matched with a corresponding volume of equal or greater capacity.

iSCSI Volume Security

Users request storage with a PersistentVolumeClaim. This claim only lives in the user’s namespace and can only be referenced by a pod within that same namespace. Any attempt to access a persistent volume across a namespace causes the pod to fail.

Each iSCSI LUN must be accessible by all nodes in the cluster.

Persistent Storage Using Fibre Channel

Overview

You can provision your OpenShift Container Platform cluster with persistent storage using Fibre Channel. Some familiarity with Kubernetes and Fibre Channel is assumed.

The Kubernetes persistent volume framework allows administrators to provision a cluster with persistent storage and gives users a way to request those resources without having any knowledge of the underlying infrastructure.

Important

High-availability of storage in the infrastructure is left to the underlying storage provider.

Provisioning

Storage must exist in the underlying infrastructure before it can be mounted as a volume in OpenShift Container Platform. All that is required for Fibre Channel persistent storage is the targetWWNs (array of Fibre Channel target’s World Wide Names), a valid LUN number, and filesystem type, and the PersistentVolume API. Note, the number of LUNs must correspond to the number of Persistent Volumes that are created. In the example below, we have LUN as 2, therefore we have created two Persistent Volume definitions.

Note

Fiber Channel does not support the 'Recycle' recycling policy.

Example 19.14. Persistent Volumes Object Definition

apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv0001
spec:
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteOnce
  fc:
    targetWWNs: ['500a0981891b8dc5', '500a0981991b8dc5']
    lun: 2
    fsType: ext4

apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv0002
spec:
  capacity:
    storage: 1Gi
  accessModes:
    - ReadOnlyMany
  fc:
    targetWWNs: ['500a0981891b8dc5', '500a0981991b8dc5']
    lun: 2
    fsType: ext4

Important

Changing the value of the fstype parameter after the volume has been formatted and provisioned can result in data loss and pod failure.

Enforcing Disk Quotas

Use LUN partitions to enforce disk quotas and size constraints. Each LUN is one persistent volume. Kubernetes enforces unique names for persistent volumes.

Enforcing quotas in this way allows the end user to request persistent storage by a specific amount (e.g, 10Gi) and be matched with a corresponding volume of equal or greater capacity.

Fibre Channel Volume Security

Users request storage with a PersistentVolumeClaim. This claim only lives in the user’s namespace and can only be referenced by a pod within that same namespace. Any attempt to access a persistent volume across a namespace causes the pod to fail.

Each Fibre Channel LUN must be accessible by all nodes in the cluster.

Dynamically Provisioning Persistent Volumes

Overview

You can provision your OpenShift Container Platform cluster with storage dynamically when running in a cloud environment. The Kubernetes persistent volume framework allows administrators to provision a cluster with persistent storage and gives users a way to request those resources without having any knowledge of the underlying infrastructure.

Many storage types are available for use as persistent volumes in OpenShift Container Platform. While all of them can be statically provisioned by an administrator, some types of storage can be created dynamically using an API. These types of storage can be provisioned in an OpenShift Container Platform cluster using the new and experimental dynamic storage feature.

Important

Dynamic provisioning of persistent volumes is currently a Technology Preview feature, introduced in OpenShift Container Platform 3.1.1. This feature is experimental and expected to change in the future as it matures and feedback is received from users. New ways to provision the cluster are planned and the means by which one accesses this feature is going to change. Backwards compatibility is not guaranteed.

Enabling Provisioner Plug-ins

OpenShift Container Platform provides the following provisioner plug-ins, which have generic implementations for dynamic provisioning that use the cluster’s configured cloud provider’s API to create new storage resources:

Storage Type
Provisioner Plug-in Name
Required Cloud Configuration
Notes

OpenStack Cinder

kubernetes.io/cinder

Configuring for OpenStack

AWS Elastic Block Store (EBS)

kubernetes.io/aws-ebs

Configuring for AWS

For dynamic provisioning when using multiple clusters in different zones, each node must be tagged with Key=KubernetesCluster,Value=clusterid.

GCE Persistent Disk (gcePD)

kubernetes.io/gce-pd

Configuring for GCE

In multi-zone configurations, it is recommended that you run one OpenShift Container Platform cluster per GCE project to avoid the creation of PVs in zones where no node from the current cluster exists.

Important

For any chosen provisioner plug-ins, the relevant cloud configuration must also be set up, per Required Cloud Configuration in the above table.

When your OpenShift Container Platform cluster is configured for EBS, GCE, or Cinder, the associated provisioner plug-in is implied and automatically enabled. No additional OpenShift Container Platform configuration by the cluster administration is required for dynamic provisioning.

For example, if your OpenShift Container Platform cluster is configured to run in AWS, the EBS provisioner plug-in is automatically available for creating dynamically provisioned storage requested by a user.

Future provisioner plug-ins will include the many types of storage a single provider offers. AWS, for example, has several types of EBS volumes to offer, each with its own performance characteristics; there is also an NFS-like storage option. More provisioner plug-ins will be implemented for the supported storage types available in OpenShift Container Platform.

Requesting Dynamically Provisioned Storage

Users can request dynamically provisioned storage by including a storage class annotation in their persistent volume claim:

Example 19.15. Persistent Volume Claim Requesting Dynamic Storage

kind: "PersistentVolumeClaim"
apiVersion: "v1"
metadata:
  name: "claim1"
  annotations:
    volume.alpha.kubernetes.io/storage-class: "foo"
spec:
  accessModes:
    - "ReadWriteOnce"
  resources:
    requests:
      storage: "3Gi"

The value of the volume.alpha.kubernetes.io/storage-class annotation is not meaningful at this time. The presence of the annotation, with any arbitrary value, triggers provisioning using the single implied provisioner plug-in per cloud.

Volume Owner Information

For dynamically provisioned storage, OpenShift Container Platform defines three key/value pairs, collectively known as the volume owner information, and arranges for the storage to associate this triplet with the provisioned volume. The keys are normally not visible to OpenShift Container Platform users, while the values are taken from user-visible PV and PVC objects.

Keys

kubernetes.io/created-for/pv/name

Name of the PersistentVolume.

Note

There is no key for the PV namespace because that has value default and cannot be changed.

kubernetes.io/created-for/pvc/namespace, kubernetes.io/created-for/pvc/name

Namespace and name, respectively, of the PersistentVolumeClaim.

Other Terms for Volume Owner Information

Each storage type saves the volume owner information in its own way. When communicating with the storage administrator, use these specific terms to avoid confusion:

Term for Key/Value Pairs
Storage Type

tags

AWS EBS

metadata

OpenStack Cinder

JSON-in-description

GCE PD

Using Volume Owner Information

The main benefit of saving the volume owner information is to enable storage administrators to recognize volumes dynamically created by OpenShift Container Platform.

Example scenarios:

OpenShift Container Platform terminates unexpectedly and the dynamically provisioned AWS EBS contains useful data that must be recovered. The OpenShift Container Platform users provide the storage administrators with a list of affected projects and their PVCs:

Project Name
PVC Name

app-server

a-pv-01

a-pv-02

notifications

n-pv-01

The storage administrators search for the orphaned volumes, matching project names and PVC names to the kubernetes.io/created-for/pvc/namespace and kubernetes.io/created-for/pvc/name tags, respectively. They find them and arrange to make them available again for data-recovery efforts.

The users do not explicitly delete the dynamically provisioned storage volumes when they are finished with a project. The storage administrators find the defunct volumes and delete them. Unlike the preceding scenario, they need match only the project names to kubernetes.io/created-for/pvc/namespace.

Volume Recycling

Volumes created dynamically by a provisioner have their persistentVolumeReclaimPolicy set to Delete. When a persistent volume claim is deleted, its backing persistent volume is considered released of its claim, and that resource can be reclaimed by the cluster. Dynamic provisioning utilizes the provider’s API to delete the volume from the provider and then removes the persistent volume from the cluster.

Volume Security

Overview

This topic provides a general guide on pod security as it relates to volume security. For information on pod-level security in general, see Managing Security Context Constraints (SCC) and the Security Context Constraint concept topic. For information on the OpenShift Container Platform persistent volume (PV) framework in general, see the Persistent Storage concept topic.

Accessing persistent storage requires coordination between the cluster and/or storage administrator and the end developer. The cluster administrator creates PVs, which abstract the underlying physical storage. The developer creates pods and, optionally, PVCs, which bind to PVs, based on matching criteria, such as capacity.

Multiple persistent volume claims (PVCs) within the same project can bind to the same PV. However, once a PVC binds to a PV, that PV cannot be bound by a claim outside of the first claim’s project. If the underlying storage needs to be accessed by multiple projects, then each project needs its own PV, which can point to the same physical storage. In this sense, a bound PV is tied to a project. For a detailed PV and PVC example, see the guide for WordPress and MySQL using NFS.

For the cluster administrator, granting pods access to PVs involves:

knowing the group ID and/or user ID assigned to the actual storage,

understanding SELinux considerations, and

ensuring that these IDs are allowed in the range of legal IDs defined for the project and/or the SCC that matches the requirements of the pod.

Group IDs, the user ID, and SELinux values are defined in the SecurityContext section in a pod definition. Group IDs are global to the pod and apply to all containers defined in the pod. User IDs can also be global, or specific to each container. Four sections control access to volumes:

supplementalGroups

fsGroup

runAsUser

seLinuxOptions

SCCs, Defaults, and Allowed Ranges

SCCs influence whether or not a pod is given a default user ID, fsGroup ID, supplemental group ID, and SELinux label. They also influence whether or not IDs supplied in the pod definition (or in the image) will be validated against a range of allowable IDs. If validation is required and fails, then the pod will also fail.

SCCs define strategies, such as runAsUser, supplementalGroups, and fsGroup. These strategies help decide whether the pod is authorized. Strategy values set to RunAsAny are essentially stating that the pod can do what it wants regarding that strategy. Authorization is skipped for that strategy and no OpenShift Container Platform default is produced based on that strategy. Therefore, IDs and SELinux labels in the resulting container are based on container defaults instead of OpenShift Container Platform policies.

For a quick summary of RunAsAny:

Any ID defined in the pod definition (or image) is allowed.

Absence of an ID in the pod definition (and in the image) results in the container assigning an ID, which is root (0) for Docker.

No SELinux labels are defined, so Docker will assign a unique label.

For these reasons, SCCs with RunAsAny for ID-related strategies should be protected so that ordinary developers do not have access to the SCC. On the other hand, SCC strategies set to MustRunAs or MustRunAsRange trigger ID validation (for ID-related strategies), and cause default values to be supplied by OpenShift Container Platform to the container when those values are not supplied directly in the pod definition or image.

Caution

Allowing access to SCCs with a RunAsAny FSGroup strategy can also prevent users from accessing their block devices. Pods need to specify an fsGroup in order to take over their block devices. Normally, this is done when the SCC FSGroup strategy is set to MustRunAs. If a user’s pod is assigned an SCC with a RunAsAny FSGroup strategy, then the user may face permission denied errors until they discover that they need to specify an fsGroup themselves.

SCCs may define the range of allowed IDs (user or groups). If range checking is required (for example, using MustRunAs) and the allowable range is not defined in the SCC, then the project determines the ID range. Therefore, projects support ranges of allowable ID. However, unlike SCCs, projects do not define strategies, such as runAsUser.

Allowable ranges are helpful not only because they define the boundaries for container IDs, but also because the minimum value in the range becomes the default value for the ID in question. For example, if the SCC ID strategy value is MustRunAs, the minimum value of an ID range is 100, and the ID is absent from the pod definition, then 100 is provided as the default for this ID.

As part of pod admission, the SCCs available to a pod are examined (roughly, in priority order followed by most restrictive) to best match the requests of the pod. Setting a SCC’s strategy type to RunAsAny is less restrictive, whereas a type of MustRunAs is more restrictive. All of these strategies are evaluated. To see which SCC was assigned to a pod, use the oc get pod command:

# oc get pod <pod_name> -o yaml
...
metadata:
  annotations:
    openshift.io/scc: nfs-scc
  name: nfs-pod1
  namespace: default
...

Name of the SCC that the pod used (in this case, a custom SCC).

Name of the pod.

Name of the project. "Namespace" is interchangeable with "project" in OpenShift Container Platform. See Projects and Users for details.

It may not be immediately obvious which SCC was matched by a pod, so the command above can be very useful in understanding the UID, supplemental groups, and SELinux relabeling in a live container.

Any SCC with a strategy set to RunAsAny allows specific values for that strategy to be defined in the pod definition (and/or image). When this applies to the user ID (runAsUser) it is prudent to restrict access to the SCC to prevent a container from being able to run as root.

Because pods often match the restricted SCC, it is worth knowing the security this entails. The restricted SCC has the following characteristics:

User IDs are constrained due to the runAsUser strategy being set to MustRunAsRange. This forces user ID validation.

Because a range of allowable user IDs is not defined in the SCC (see oc export scc restricted for more details), the project’s openshift.io/sa.scc.uid-range range will be used for range checking and for a default ID, if needed.

A default user ID is produced when a user ID is not specified in the pod definition due to runAsUser being set to MustRunAsRange.

An SELinux label is required (seLinuxContext set to MustRunAs), which uses the project’s default MCS label.

fsGroup IDs are constrained to a single value due to the FSGroup strategy being set to MustRunAs, which dictates that the value to use is the minimum value of the first range specified.

Because a range of allowable fsGroup IDs is not defined in the SCC, the minimum value of the project’s openshift.io/sa.scc.supplemental-groups range (or the same range used for user IDs) will be used for validation and for a default ID, if needed.

A default fsGroup ID is produced when a fsGroup ID is not specified in the pod and the matching SCC’s FSGroup is set to MustRunAs.

Arbitrary supplemental group IDs are allowed because no range checking is required. This is a result of the supplementalGroups strategy being set to RunAsAny.

Default supplemental groups are not produced for the running pod due to RunAsAny for the two group strategies above. Therefore, if no groups are defined in the pod definition (or in the image), the container(s) will have no supplemental groups predefined.

The following shows the default project and a custom SCC (my-custom-scc), which summarizes the interactions of the SCC and the project:

$ oc get project default -o yaml
...
metadata:
  annotations:
    openshift.io/sa.scc.mcs: s0:c1,c0
    openshift.io/sa.scc.supplemental-groups: 1000000000/10000
    openshift.io/sa.scc.uid-range: 1000000000/10000

$ oc get scc my-custom-scc -o yaml
...
fsGroup:
  type: MustRunAs
  ranges:
  - min: 5000
    max: 6000
runAsUser:
  type: MustRunAsRange
  uidRangeMin: 65534
  uidRangeMax: 65634
seLinuxContext:
  type: MustRunAs
  SELinuxOptions:
    user: <selinux-user-name>
    role: ...
    type: ...
    level: ...
supplementalGroups:
  type: MustRunAs
  ranges:
  - min: 5000
    max: 6000

default is the name of the project.

Default values are only produced when the corresponding SCC strategy is not RunAsAny.

SELinux default when not defined in the pod definition or in the SCC.

Range of allowable group IDs. ID validation only occurs when the SCC strategy is RunAsAny. There can be more than one range specified, separated by commas. See below for supported formats.

Same as <4> but for user IDs. Also, only a single range of user IDs is supported.

MustRunAs enforces group ID range checking and provides the container’s groups default. Based on this SCC definition, the default is 5000 (the minimum ID value). If the range was omitted from the SCC, then the default would be 1000000000 (derived from the project). The other supported type, RunAsAny, does not perform range checking, thus allowing any group ID, and produces no default groups.

MustRunAsRange enforces user ID range checking and provides a UID default. Based on this SCC, the default UID is 65534 (the minimum value). If the minimum *and maximum range were omitted from the SCC, the default user ID would be *1000000000 (derived from the project). *MustRunAsNonRoot and RunAsAny are *the other supported types. The range of allowed IDs can be defined to include *any user IDs required for the target storage.

When set to MustRunAs, the container is created with the SCC’s SELinux options, or the MCS default defined in the project. A type of RunAsAny indicates that SELinux context is not required, and, if not defined in the pod, is not set in the container.

The SELinux user name, role name, type, and labels can be defined here.

Two formats are supported for allowed ranges:

M/N, where M is the starting ID and N is the count, so the range becomes M through (and including) M+N-1.

M-N, where M is again the starting ID and N is the ending ID. The default group ID is the starting ID in the first range, which is 1000000000 in this project. If the SCC did not define a minimum group ID, then the project’s default ID is applied.

Supplemental Groups

Note

Read SCCs, Defaults, and Allowed Ranges before working with supplemental groups.

Tip

It is generally preferable to use group IDs (supplemental or fsGroup) to gain access to persistent storage versus using user IDs.

Supplemental groups are regular Linux groups. When a process runs in Linux, it has a UID, a GID, and one or more supplemental groups. These attributes can be set for a container’s main process. The supplementalGroups IDs are typically used for controlling access to shared storage, such as NFS and GlusterFS, whereas fsGroup is used for controlling access to block storage, such as Ceph RBD and iSCSI.

The OpenShift Container Platform shared storage plug-ins mount volumes such that the POSIX permissions on the mount match the permissions on the target storage. For example, if the target storage’s owner ID is 1234 and its group ID is 5678, then the mount on the host node and in the container will have those same IDs. Therefore, the container’s main process must match one or both of those IDs in order to access the volume.

For example, consider the following NFS export.

On an OpenShift Container Platform node:

Note

showmount requires access to the ports used by rpcbind and rpc.mount on the NFS server

# showmount -e <nfs-server-ip-or-hostname>
Export list for f21-nfs.vm:
/opt/nfs  *

On the NFS server:

# cat /etc/exports
/opt/nfs *(rw,sync,root_squash)
...

# ls -lZ /opt/nfs -d
drwxrws---. nfsnobody 5555 unconfined_u:object_r:usr_t:s0   /opt/nfs

# id nfsnobody
uid=65534(nfsnobody) gid=65534(nfsnobody) groups=65534(nfsnobody)

Note

In the above, the owner is 65534 (nfsnobody), but the suggestions and examples in this topic apply to any non-root owner.

The /opt/nfs/ export is accessible by UID 65534 and the group 5555. In general, containers should not run as root, so in this NFS example, containers which are not run as UID 65534 or are not members the group 5555 will not be able to access the NFS export.

Often, the SCC matching the pod does not allow a specific user ID to be specified, thus using supplemental groups is a more flexible way to grant storage access to a pod. For example, to grant NFS access to the export above, the group 5555 can be defined in the pod definition:

apiVersion: v1
kind: Pod
...
spec:
  containers:
  - name: ...
    volumeMounts:
    - name: nfs
      mountPath: /usr/share/...
  securityContext:
    supplementalGroups: [5555]
  volumes:
  - name: nfs
    nfs:
      server: <nfs_server_ip_or_host>
      path: /opt/nfs

Name of the volume mount. Must match the name in the volumes section.

NFS export path as seen in the container.

Pod global security context. Applies to all containers in the pod. Each container can also define its securityContext, however group IDs are global to the pod and cannot be defined for individual containers.

Supplemental groups, which is an array of IDs, is set to 5555. This grants group access to the export.

Name of the volume. Must match the name in the volumeMounts section.

Actual NFS export path on the NFS server.

All containers in the above pod (assuming the matching SCC or project allows the group 5555) will be members of the group 5555 and have access to the volume, regardless of the container’s user ID. However, the assumption above is critical. Sometimes, the SCC does not define a range of allowable group IDs but requires group ID validation (due to supplementalGroups set to MustRunAs; note this is not the case for the restricted SCC). The project will not likely allow a group ID of 5555, unless the project has been customized for access to this NFS export. So in this scenario, the above pod will fail because its group ID of 5555 is not within the SCC’s or the project’s range of allowed group IDs.

Supplemental Groups and Custom SCCs

To remedy the situation in the previous example, a custom SCC can be created such that:

a minimum and max group ID are defined,

ID range checking is enforced, and

the group ID of 5555 is allowed.

It is better to create new SCCs versus modifying a predefined SCC, or changing the range of allowed IDs in the predefined projects.

The easiest way to create a new SCC is to export an existing SCC and customize the YAML file to meet the requirements of the new SCC. For example:

Use the restricted SCC as a template for the new SCC:

$ oc export scc restricted > new-scc.yaml

Edit the new-scc.yaml file to your desired specifications.

Create the new SCC:

$ oc create -f new-scc.yaml

Note

The oc edit scc command can be used to modify an instantiated SCC.

Here is a fragment of a new SCC named nfs-scc:

$ oc export scc nfs-scc

allowHostDirVolumePlugin: false
...
kind: SecurityContextConstraints
metadata:
  ...
  name: nfs-scc
priority: 9
...
supplementalGroups:
  type: MustRunAs
  ranges:
  -  min: 5000
     max: 6000
...

The allow* bools are the same as for the restricted SCC.

Name of the new SCC.

Numerically larger numbers have greater priority. Nil or omitted is the lowest priority. Higher priority SCCs sort before lower priority SCCs and thus have a better chance of matching a new pod.

supplementalGroups is a strategy and it is set to MustRunAs, which means group ID checking is required.

Multiple ranges are supported. The allowed group ID range here is 5000 through 5999, with the default supplemental group being 5000.

When the same pod shown earlier runs against this new SCC (assuming, of course, the pod has access to the new SCC), it will start because the group 5555, supplied in the pod definition, is now allowed by the custom SCC.

fsGroup

Note

Read SCCs, Defaults, and Allowed Ranges before working with supplemental groups.

Tip

It is generally preferable to use group IDs (supplemental or fsGroup) to gain access to persistent storage versus using user IDs.

fsGroup defines a pod’s "file system group" ID, which is added to the container’s supplemental groups. The supplementalGroups ID applies to shared storage, whereas the fsGroup ID is used for block storage.

Block storage, such as Ceph RBD, iSCSI, and various cloud storage, is typically dedicated to a single pod which has requested the block storage volume, either directly or using a PVC. Unlike shared storage, block storage is taken over by a pod, meaning that user and group IDs supplied in the pod definition (or image) are applied to the actual, physical block device. Typically, block storage is not shared.

A fsGroup definition is shown below in the following pod definition fragment:

kind: Pod
...
spec:
  containers:
  - name: ...
  securityContext:
    fsGroup: 5555
  ...

As with supplementalGroups, fsGroup must be defined globally to the pod, not per container.

5555 will become the group ID for the volume’s group permissions and for all new files created in the volume.

As with supplementalGroups, all containers in the above pod (assuming the matching SCC or project allows the group 5555) will be members of the group 5555, and will have access to the block volume, regardless of the container’s user ID. If the pod matches the restricted SCC, whose fsGroup strategy is MustRunAs, then the pod will fail to run. However, if the SCC has its fsGroup strategy set to RunAsAny, then any fsGroup ID (including 5555) will be accepted. Note that if the SCC has its fsGroup strategy set to RunAsAny and no fsGroup ID is specified, the "taking over" of the block storage does not occur and permissions may be denied to the pod.

fsGroups and Custom SCCs

To remedy the situation in the previous example, a custom SCC can be created such that:

a minimum and maximum group ID are defined,

ID range checking is enforced, and

the group ID of 5555 is allowed.

It is better to create new SCCs versus modifying a predefined SCC, or changing the range of allowed IDs in the predefined projects.

Consider the following fragment of a new SCC definition:

# oc export scc new-scc
...
kind: SecurityContextConstraints
...
fsGroup:
  type: MustRunAs
  ranges:
  - max: 6000
    min: 5000
...

MustRunAs triggers group ID range checking, whereas RunAsAny does not require range checking.

The range of allowed group IDs is 5000 through, and including, 5999. Multiple ranges are supported. The allowed group ID range here is 5000 through 5999, with the default fsGroup being 5000.

The minimum value (or the entire range) can be omitted from the SCC, and thus range checking and generating a default value will defer to the project’s openshift.io/sa.scc.supplemental-groups range. fsGroup and supplementalGroups use the same group field in the project; there is not a separate range for fsGroup.

When the pod shown above runs against this new SCC (assuming, of course, the pod has access to the new SCC), it will start because the group 5555, supplied in the pod definition, is allowed by the custom SCC. Additionally, the pod will "take over" the block device, so when the block storage is viewed by a process outside of the pod, it will actually have 5555 as its group ID.

Currently the list of volumes which support block ownership (block) management include:

AWS Elastic Block Store

OpenStack Cinder

Ceph RBD

GCE Persistent Disk

iSCSI

emptyDir

gitRepo

User IDs

Note

Read SCCs, Defaults, and Allowed Ranges before working with supplemental groups.

Tip

It is generally preferable to use group IDs (supplemental or fsGroup) to gain access to persistent storage versus using user IDs.

User IDs can be defined in the container image or in the pod definition. In the pod definition, a single user ID can be defined globally to all containers, or specific to individual containers (or both). A user ID is supplied as shown in the pod definition fragment below:

spec:
  containers:
  - name: ...
    securityContext:
      runAsUser: 65534

ID 65534 in the above is container-specific and matches the owner ID on the export. If the NFS export’s owner ID was 54321, then that number would be used in the pod definition. Specifying securityContext outside of the container definition makes the ID global to all containers in the pod.

Similar to group IDs, user IDs may be validated according to policies set in the SCC and/or project. If the SCC’s runAsUser strategy is set to RunAsAny, then any user ID defined in the pod definition or in the image is allowed.

Warning

This means even a UID of 0 (root) is allowed.

If, instead, the runAsUser strategy is set to MustRunAsRange, then a supplied user ID will be validated against a range of allowed IDs. If the pod supplies no user ID, then the default ID is the minimum value of the range of allowable user IDs.

Returning to the earlier NFS example, the container needs its UID set to 65534, which is shown in the pod fragment above. Assuming the default project and the restricted SCC, the pod’s requested user ID of 65534 will not be allowed, and therefore the pod will fail. The pod fails because:

it requests 65534 as its user ID,

all available SCCs use MustRunAsRange for their runAsUser strategy, so UID range checking is required, and

65534 is not included in the SCC or project’s user ID range.

To address this situation, the recommended path would be to create a new SCC with the appropriate user ID range. A new project could also be created with the appropriate user ID range defined. There are other, less-preferred options:

The restricted SCC could be modified to include 65534 within its minimum and maximum user ID range. This is not recommended as you should avoid modifying the predefined SCCs if possible.

The restricted SCC could be modified to use RunAsAny for the runAsUser value, thus eliminating ID range checking. This is strongly not recommended, as containers could run as root.

The default project’s UID range could be changed to allow a user ID of 65534. This is not generally advisable because only a single range of user IDs can be specified.

User IDs and Custom SCCs

It is good practice to avoid modifying the predefined SCCs if possible. The preferred approach is to create a custom SCC that better fits an organization’s security needs, or create a new project that supports the desired user IDs.

To remedy the situation in the previous example, a custom SCC can be created such that:

a minimum and maximum user ID is defined,

UID range checking is still enforced, and

the UID of 65534 will be allowed.

For example:

$ oc export scc nfs-scc

allowHostDirVolumePlugin: false
...
kind: SecurityContextConstraints
metadata:
  ...
  name: nfs-scc
priority: 9
requiredDropCapabilities: null
runAsUser:
  type: MustRunAsRange
  uidRangeMax: 65534
  uidRangeMin: 65534
...

The allow* bools are the same as for the restricted SCC.

The name of this new SCC is nfs-scc.

Numerically larger numbers have greater priority. Nil or omitted is the lowest priority. Higher priority SCCs sort before lower priority SCCs, and thus have a better chance of matching a new pod.

The runAsUser strategy is set to MustRunAsRange, which means UID range checking is enforced.

The UID range is 65534 through 65534 (a range of one value).

Now, with runAsUser: 65534 shown in the previous pod definition fragment, the pod matches the new nfs-scc and is able to run with a UID of 65534.

SELinux Options

All predefined SCCs, except for the privileged SCC, set the seLinuxContext to MustRunAs. So the SCCs most likely to match a pod’s requirements will force the pod to use an SELinux policy. The SELinux policy used by the pod can be defined in the pod itself, in the image, in the SCC, or in the project (which provides the default).

SELinux labels can be defined in a pod’s securityContext.seLinuxOptions section, and supports user, role, type, and level:

Note

Level and MCS label are used interchangeably in this topic.

...
 securityContext:
    seLinuxOptions:
      level: "s0:c123,c456"
...

level can be defined globally for the entire pod, or individually for each container.

SELinux level label.

Here are fragments from an SCC and from the default project:

$ oc export scc scc-name
...
seLinuxContext:
  type: MustRunAs

# oc export project default
...
metadata:
  annotations:
    openshift.io/sa.scc.mcs: s0:c1,c0
...

MustRunAs causes volume relabeling.

If the label is not provided in the pod or in the SCC, then the default comes from the project.

All predefined SCCs, except for the privileged SCC, set the seLinuxContext to MustRunAs. This forces pods to use MCS labels, which can be defined in the pod definition, the image, or provided as a default.

The SCC determines whether or not to require an SELinux label and can provide a default label. If the seLinuxContext strategy is set to MustRunAs and the pod (or image) does not define a label, OpenShift Container Platform defaults to a label chosen from the SCC itself or from the project.

If seLinuxContext is set to RunAsAny, then no default labels are provided, and the container determines the final label. In the case of Docker, the container will use a unique MCS label, which will not likely match the labeling on existing storage mounts. Volumes which support SELinux management will be relabeled so that they are accessible by the specified label and, depending on how exclusionary the label is, only that label.

This means two things for unprivileged containers:

The volume will be given a type which is accessible by unprivileged containers. This type is usually svirt_sandbox_file_t.

If a level is specified, the volume will be labeled with the given MCS label.

For a volume to be accessible by a pod, the pod must have both categories of the volume. So a pod with s0:c1,c2 will be able to access a volume with s0:c1,c2. A volume with s0 will be accessible by all pods.

If pods fail authorization, or if the storage mount is failing due to permissions errors, then there is a possibility that SELinux enforcement is interfering. One way to check for this is to run:

# ausearch -m avc --start recent

This examines the log file for AVC (Access Vector Cache) errors.

Selector-Label Volume Binding

Overview

This guide provides the steps necessary to enable binding of persistent volume claims (PVCs) to persistent volumes (PVs) via selector and label attributes. By implementing selectors and labels, regular users are able to target provisioned storage by identifiers defined by a cluster administrator.

Motivation

In cases of statically provisioned storage, developers seeking persistent storage are required to know a handful identifying attributes of a PV in order to deploy and bind a PVC. This creates several problematic situations. Regular users might have to contact a cluster administrator to either deploy the PVC or provide the PV values. PV attributes alone do not convey the intended use of the storage volumes, nor do they provide methods by which volumes can be grouped.

Selector and label attributes can be used to abstract away PV details from the user while providing cluster administrators a way of identifying volumes by a descriptive and customizable tag. Through the selector-label method of binding, users are only required to know which labels are defined by the administrator.

Note

The selector-label feature is currently only available for statically provisioned storage and is currently not implemented for storage provisioned dynamically.

Deployment

This section reviews how to define and deploy PVCs.

Prerequisites

A running OpenShift Container Platform 3.3+ cluster

A volume provided by a supported storage provider

A user with a cluster-admin role binding

Define the Persistent Volume and Claim

As the cluser-admin user, define the PV. For this example, we will be using a GlusterFS volume. See the appropriate storage provider for your provider’s configuration.

Example 19.16. Persistent Volume with Labels

apiVersion: v1
kind: PersistentVolume
metadata:
  name: gluster-volume
  labels:
    volume-type: ssd
    aws-availability-zone: us-east-1
spec:
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteMany
  glusterfs:
    endpoints: glusterfs-cluster
    path: myVol1
    readOnly: false
  persistentVolumeReclaimPolicy: Recycle

A PVC whose selectors match all of a PV’s labels will be bound, assuming a PV is available.

Define the PVC:

Example 19.17. Persistent Volume Claim with Selectors

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: gluster-claim
spec:
  accessModes:
  - ReadWriteMany
  resources:
     requests:
       storage: 1Gi
  selector:
    matchLabels:
      volume-type: ssd
      aws-availability-zone: us-east-1

Begin selectors section.

List all labels by which the user is requesting storage. Must match all labels of targeted PV.

Deploy the Persistent Volume and Claim

As the cluster-admin user, create the persistent volume:

Example 19.18. Create the Persistent Volume

# oc create -f gluster-pv.yaml
persistentVolume "gluster-volume" created

# oc get pv
NAME                     LABELS    CAPACITY     ACCESSMODES   STATUS      CLAIM     REASON    AGE
gluster-volume            map[]    2147483648   RWX           Available                       2s

Once the PV is created, any user whose selectors match all its labels can create their PVC.

Example 19.19. Create the Persistent Volume Claim

# oc create -f gluster-pvc.yaml
persistentVolumeClaim "gluster-claim" created
# oc get pvc
NAME          LABELS    STATUS    VOLUME
gluster-claim           Bound     gluster-volume

Chapter 20. Persistent Storage Examples

Overview

The following sections provide detailed, comprehensive instructions on setting up and configuring common storage use cases. These examples cover both the administration of persistent volumes and their security, and how to claim against the volumes as a user of the system.

Sharing an NFS PV Across Two Pods

Ceph-RBD Block Storage Volume

Shared Storage Using a GlusterFS Volume

Backing Docker Registry with GlusterFS Storage

Binding Persistent Volumes by Labels

Sharing an NFS mount across two persistent volume claims

Overview

The following use case describes how a cluster administrator wanting to leverage shared storage for use by two separate containers would configure the solution. This example highlights the use of NFS, but can easily be adapted to other shared storage types, such as GlusterFS. In addition, this example will show configuration of pod security as it relates to shared storage.

Persistent Storage Using NFS provides an explanation of persistent volumes (PVs), persistent volume claims (PVCs), and using NFS as persistent storage. This topic shows and end-to-end example of using an existing NFS cluster and OpenShift Container Platform persistent store, and assumes an existing NFS server and exports exist in your OpenShift Container Platform infrastructure.

Note

All oc commands are executed on the OpenShift Container Platform master host.

Creating the Persistent Volume

Before creating the PV object in OpenShift Container Platform, the persistent volume (PV) file is defined:

Example 20.1. Persistent Volume Object Definition Using NFS

apiVersion: v1
kind: PersistentVolume
metadata:
  name: nfs-pv
spec:
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteMany
  persistentVolumeReclaimPolicy: Retain
  nfs:
    path: /opt/nfs
    server: nfs.f22
    readOnly: false

The name of the PV, which is referenced in pod definitions or displayed in various oc volume commands.

The amount of storage allocated to this volume.

accessModes are used as labels to match a PV and a PVC. They currently do not define any form of access control.

A volume reclaim policy of retain indicates to preserve the volume after the pods.

This defines the volume type being used, in this case the NFS plug-in.

This is the NFS mount path.

This is the NFS server. This can also be specified by IP address.

Save the PV definition to a file, for example nfs-pv.yaml, and create the persistent volume:

# oc create -f nfs-pv.yaml
persistentvolume "nfs-pv" created

Verify that the persistent volume was created:

# oc get pv
NAME         LABELS    CAPACITY   ACCESSMODES   STATUS      CLAIM     REASON    AGE
nfs-pv       <none>    1Gi        RWX           Available                       37s

Creating the Persistent Volume Claim

A persistent volume claim (PVC) specifies the desired access mode and storage capacity. Currently, based on only these two attributes, a PVC is bound to a single PV. Once a PV is bound to a PVC, that PV is essentially tied to the PVC’s project and cannot be bound to by another PVC. There is a one-to-one mapping of PVs and PVCs. However, multiple pods in the same project can use the same PVC. This is the use case we are highlighting in this example.

Example 20.2. PVC Object Definition

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: nfs-pvc
spec:
  accessModes:
  - ReadWriteMany
  resources:
     requests:
       storage: 1Gi

The claim name is referenced by the pod under its volumes section.

As mentioned above for PVs, the accessModes do not enforce access right, but rather act as labels to match a PV to a PVC.

This claim will look for PVs offering 1Gi or greater capacity.

Save the PVC definition to a file, for example nfs-pvc.yaml, and create the PVC:

# oc create -f nfs-pvc.yaml
persistentvolumeclaim "nfs-pvc" created

Verify that the PVC was created and bound to the expected PV:

# oc get pvc
NAME            LABELS    STATUS    VOLUME       CAPACITY   ACCESSMODES   AGE
nfs-pvc         <none>    Bound     nfs-pv       1Gi        RWX           24s

The claim, nfs-pvc, was bound to the nfs-pv PV.

Ensuring NFS Volume Access

Access is necessary to a node in the NFS server. On this node, examine the NFS export mount:

[root@nfs nfs]# ls -lZ /opt/nfs/
total 8
-rw-r--r--. 1 root 100003  system_u:object_r:usr_t:s0     10 Oct 12 23:27 test2b

the owner has ID 0.

the group has ID 100003.

In order to access the NFS mount, the container must match the SELinux label, and either run with a UID of 0, or with 100003 in its supplemental groups range. Gain access to the volume by matching the NFS mount’s groups, which will be defined in the pod definition below.

By default, SELinux does not allow writing from a pod to a remote NFS server. To enable writing to NFS volumes with SELinux enforcing on each node, run:

# setsebool -P virt_sandbox_use_nfs on
# setsebool -P virt_use_nfs on

Note

The virt_sandbox_use_nfs boolean is defined by the docker-selinux package. If you get an error saying it is not defined, ensure that this package is installed.

Creating the Pod

A pod definition file or a template file can be used to define a pod. Below is a pod specification that creates a single container and mounts the NFS volume for read-write access:

Example 20.3. Pod Object Definition

apiVersion: v1
kind: Pod
metadata:
  name: nginx-nfs-pod
  labels:
    name: nginx-nfs-pod
spec:
  containers:
    - name: nginx-nfs-pod
      image: fedora/nginx
      ports:
        - name: web
          containerPort: 80
      volumeMounts:
        - name: nfsvol
          mountPath: /usr/share/nginx/html
  securityContext:
      supplementalGroups: [100003]
      privileged: false
  volumes:
    - name: nfsvol
      persistentVolumeClaim:
        claimName: nfs-pvc

The name of this pod as displayed by oc get pod.

The image run by this pod.

The name of the volume. This name must be the same in both the containers and volumes sections.

The mount path as seen in the container.

The group ID to be assigned to the container.

The PVC that was created in the previous step.

Save the pod definition to a file, for example nfs.yaml, and create the pod:

# oc create -f nfs.yaml
pod "nginx-nfs-pod" created

Verify that the pod was created:

# oc get pods
NAME                READY     STATUS    RESTARTS   AGE
nginx-nfs-pod       1/1       Running   0          4s

More details are shown in the oc describe pod command:

[root@ose70 nfs]# oc describe pod nginx-nfs-pod
Name:				nginx-nfs-pod
Namespace:			default
Image(s):			fedora/nginx
Node:				ose70.rh7/192.168.234.148
Start Time:			Mon, 21 Mar 2016 09:59:47 -0400
Labels:				name=nginx-nfs-pod
Status:				Running
Reason:
Message:
IP:				10.1.0.4
Replication Controllers:	<none>
Containers:
  nginx-nfs-pod:
    Container ID:	docker://a3292104d6c28d9cf49f440b2967a0fc5583540fc3b062db598557b93893bc6f
    Image:		fedora/nginx
    Image ID:		docker://403d268c640894cbd76d84a1de3995d2549a93af51c8e16e89842e4c3ed6a00a
    QoS Tier:
      cpu:		BestEffort
      memory:		BestEffort
    State:		Running
      Started:		Mon, 21 Mar 2016 09:59:49 -0400
    Ready:		True
    Restart Count:	0
    Environment Variables:
Conditions:
  Type		Status
  Ready 	True
Volumes:
  nfsvol:
    Type:	PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
    ClaimName:	nfs-pvc
    ReadOnly:	false
  default-token-a06zb:
    Type:	Secret (a secret that should populate this volume)
    SecretName:	default-token-a06zb
Events:
  FirstSeen	LastSeen	Count	From			SubobjectPath				Reason		Message
  ─────────	────────	─────	────			─────────────				──────		───────
  4m		4m		1	{scheduler }							Scheduled	Successfully assigned nginx-nfs-pod to ose70.rh7
  4m		4m		1	{kubelet ose70.rh7}	implicitly required container POD	Pulled		Container image "openshift3/ose-pod:v3.1.0.4" already present on machine
  4m		4m		1	{kubelet ose70.rh7}	implicitly required container POD	Created		Created with docker id 866a37108041
  4m		4m		1	{kubelet ose70.rh7}	implicitly required container POD	Started		Started with docker id 866a37108041
  4m		4m		1	{kubelet ose70.rh7}	spec.containers{nginx-nfs-pod}		Pulled		Container image "fedora/nginx" already present on machine
  4m		4m		1	{kubelet ose70.rh7}	spec.containers{nginx-nfs-pod}		Created		Created with docker id a3292104d6c2
  4m		4m		1	{kubelet ose70.rh7}	spec.containers{nginx-nfs-pod}		Started		Started with docker id a3292104d6c2

The project (namespace) name.

The IP address of the OpenShift Container Platform node running the pod.

The PVC name used by the pod.

The list of events resulting in the pod being launched and the NFS volume being mounted. The container will not start correctly if the volume cannot mount.

There is more internal information, including the SCC used to authorize the pod, the pod’s user and group IDs, the SELinux label, and more, shown in the oc get pod <name> -o yaml command:

[root@ose70 nfs]# oc get pod nginx-nfs-pod -o yaml
apiVersion: v1
kind: Pod
metadata:
  annotations:
    openshift.io/scc: restricted
  creationTimestamp: 2016-03-21T13:59:47Z
  labels:
    name: nginx-nfs-pod
  name: nginx-nfs-pod
  namespace: default
  resourceVersion: "2814411"
  selflink: /api/v1/namespaces/default/pods/nginx-nfs-pod
  uid: 2c22d2ea-ef6d-11e5-adc7-000c2900f1e3
spec:
  containers:
  - image: fedora/nginx
    imagePullPolicy: IfNotPresent
    name: nginx-nfs-pod
    ports:
    - containerPort: 80
      name: web
      protocol: TCP
    resources: {}
    securityContext:
      privileged: false
    terminationMessagePath: /dev/termination-log
    volumeMounts:
    - mountPath: /usr/share/nginx/html
      name: nfsvol
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: default-token-a06zb
      readOnly: true
  dnsPolicy: ClusterFirst
  host: ose70.rh7
  imagePullSecrets:
  - name: default-dockercfg-xvdew
  nodeName: ose70.rh7
  restartPolicy: Always
  securityContext:
    supplementalGroups:
    - 100003
  serviceAccount: default
  serviceAccountName: default
  terminationGracePeriodSeconds: 30
  volumes:
  - name: nfsvol
    persistentVolumeClaim:
      claimName: nfs-pvc
  - name: default-token-a06zb
    secret:
      secretName: default-token-a06zb
status:
  conditions:
  - lastProbeTime: null
    lastTransitionTime: 2016-03-21T13:59:49Z
    status: "True"
    type: Ready
  containerStatuses:
  - containerID: docker://a3292104d6c28d9cf49f440b2967a0fc5583540fc3b062db598557b93893bc6f
    image: fedora/nginx
    imageID: docker://403d268c640894cbd76d84a1de3995d2549a93af51c8e16e89842e4c3ed6a00a
    lastState: {}
    name: nginx-nfs-pod
    ready: true
    restartCount: 0
    state:
      running:
        startedAt: 2016-03-21T13:59:49Z
  hostIP: 192.168.234.148
  phase: Running
  podIP: 10.1.0.4
  startTime: 2016-03-21T13:59:47Z

The SCC used by the pod.

The project (namespace) name.

The supplemental group ID for the pod (all containers).

The PVC name used by the pod.

Creating an Additional Pod to Reference the Same PVC

This pod definition, created in the same namespace, uses a different container. However, we can use the same backing storage by specifying the claim name in the volumes section below:

Example 20.4. Pod Object Definition

apiVersion: v1
kind: Pod
metadata:
  name: busybox-nfs-pod
  labels:
    name: busybox-nfs-pod
spec:
  containers:
  - name: busybox-nfs-pod
    image: busybox
    command: ["sleep", "60000"]
    volumeMounts:
    - name: nfsvol-2
      mountPath: /usr/share/busybox
      readOnly: false
  securityContext:
    supplementalGroups: [100003]
    privileged: false
  volumes:
  - name: nfsvol-2
    persistentVolumeClaim:
      claimName: nfs-pvc

The name of this pod as displayed by oc get pod.

The image run by this pod.

The name of the volume. This name must be the same in both the containers and volumes sections.

The mount path as seen in the container.

The group ID to be assigned to the container.

The PVC that was created earlier and is also being used by a different container.

Save the pod definition to a file, for example nfs-2.yaml, and create the pod:

# oc create -f nfs-2.yaml
pod "busybox-nfs-pod" created

Verify that the pod was created:

# oc get pods
NAME                READY     STATUS    RESTARTS   AGE
busybox-nfs-pod     1/1       Running   0          3s

More details are shown in the oc describe pod command:

[root@ose70 nfs]# oc describe pod busybox-nfs-pod
Name:				busybox-nfs-pod
Namespace:			default
Image(s):			busybox
Node:				ose70.rh7/192.168.234.148
Start Time:			Mon, 21 Mar 2016 10:19:46 -0400
Labels:				name=busybox-nfs-pod
Status:				Running
Reason:
Message:
IP:				10.1.0.5
Replication Controllers:	<none>
Containers:
  busybox-nfs-pod:
    Container ID:	docker://346d432e5a4824ebf5a47fceb4247e0568ecc64eadcc160e9bab481aecfb0594
    Image:		busybox
    Image ID:		docker://17583c7dd0dae6244203b8029733bdb7d17fccbb2b5d93e2b24cf48b8bfd06e2
    QoS Tier:
      cpu:		BestEffort
      memory:		BestEffort
    State:		Running
      Started:		Mon, 21 Mar 2016 10:19:48 -0400
    Ready:		True
    Restart Count:	0
    Environment Variables:
Conditions:
  Type		Status
  Ready 	True
Volumes:
  nfsvol-2:
    Type:	PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
    ClaimName:	nfs-pvc
    ReadOnly:	false
  default-token-32d2z:
    Type:	Secret (a secret that should populate this volume)
    SecretName:	default-token-32d2z
Events:
  FirstSeen	LastSeen	Count	From			SubobjectPath				Reason		Message
  ─────────	────────	─────	────			─────────────				──────		───────
  4m		4m		1	{scheduler }							Scheduled	Successfully assigned busybox-nfs-pod to ose70.rh7
  4m		4m		1	{kubelet ose70.rh7}	implicitly required container POD	Pulled		Container image "openshift3/ose-pod:v3.1.0.4" already present on machine
  4m		4m		1	{kubelet ose70.rh7}	implicitly required container POD	Created		Created with docker id 249b7d7519b1
  4m		4m		1	{kubelet ose70.rh7}	implicitly required container POD	Started		Started with docker id 249b7d7519b1
  4m		4m		1	{kubelet ose70.rh7}	spec.containers{busybox-nfs-pod}	Pulled		Container image "busybox" already present on machine
  4m		4m		1	{kubelet ose70.rh7}	spec.containers{busybox-nfs-pod}	Created		Created with docker id 346d432e5a48
  4m		4m		1	{kubelet ose70.rh7}	spec.containers{busybox-nfs-pod}	Started		Started with docker id 346d432e5a48

As you can see, both containers are using the same storage claim that is attached to the same NFS mount on the back end.

Complete Example Using Ceph RBD

Overview

This topic provides an end-to-end example of using an existing Ceph cluster as an OpenShift Container Platform persistent store. It is assumed that a working Ceph cluster is already set up. If not, consult the Overview of Red Hat Ceph Storage.

Persistent Storage Using Ceph Rados Block Device provides an explanation of persistent volumes (PVs), persistent volume claims (PVCs), and using Ceph RBD as persistent storage.

Note

All oc …​ commands are executed on the OpenShift Container Platform master host.

Installing the ceph-common Package

The ceph-common library must be installed on all schedulable OpenShift Container Platform nodes:

Note

The OpenShift Container Platform all-in-one host is not often used to run pod workloads and, thus, is not included as a schedulable node.

# yum install -y ceph-common

Creating the Ceph Secret

The ceph auth get-key command is run on a Ceph MON node to display the key value for the client.admin user:

Example 20.5. Ceph Secret Definition

apiVersion: v1
kind: Secret
metadata:
  name: ceph-secret
data:
  key: QVFBOFF2SlZheUJQRVJBQWgvS2cwT1laQUhPQno3akZwekxxdGc9PQ==

This base64 key is generated on one of the Ceph MON nodes using the ceph auth get-key client.admin | base64 command, then copying the output and pasting it as the secret key’s value.

Save the secret definition to a file, for example ceph-secret.yaml, then create the secret:

$ oc create -f ceph-secret.yaml
secret "ceph-secret" created

Verify that the secret was created:

# oc get secret ceph-secret
NAME          TYPE      DATA      AGE
ceph-secret   Opaque    1         23d

Creating the Persistent Volume

Next, before creating the PV object in OpenShift Container Platform, define the persistent volume file:

Example 20.6. Persistent Volume Object Definition Using Ceph RBD

apiVersion: v1
kind: PersistentVolume
metadata:
  name: ceph-pv
spec:
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteOnce
  rbd:
    monitors:
      - 192.168.122.133:6789
    pool: rbd
    image: ceph-image
    user: admin
    secretRef:
      name: ceph-secret
    fsType: ext4
    readOnly: false
  persistentVolumeReclaimPolicy: Recycle

The name of the PV, which is referenced in pod definitions or displayed in various oc volume commands.

The amount of storage allocated to this volume.

accessModes are used as labels to match a PV and a PVC. They currently do not define any form of access control. All block storage is defined to be single user (non-shared storage).

This defines the volume type being used. In this case, the rbd plug-in is defined.

This is an array of Ceph monitor IP addresses and ports.

This is the Ceph secret, defined above. It is used to create a secure connection from OpenShift Container Platform to the Ceph server.

This is the file system type mounted on the Ceph RBD block device.

Save the PV definition to a file, for example ceph-pv.yaml, and create the persistent volume:

# oc create -f ceph-pv.yaml
persistentvolume "ceph-pv" created

Verify that the persistent volume was created:

# oc get pv
NAME                     LABELS    CAPACITY     ACCESSMODES   STATUS      CLAIM     REASON    AGE
ceph-pv                  <none>    2147483648   RWO           Available                       2s

Creating the Persistent Volume Claim

A persistent volume claim (PVC) specifies the desired access mode and storage capacity. Currently, based on only these two attributes, a PVC is bound to a single PV. Once a PV is bound to a PVC, that PV is essentially tied to the PVC’s project and cannot be bound to by another PVC. There is a one-to-one mapping of PVs and PVCs. However, multiple pods in the same project can use the same PVC.

Example 20.7. PVC Object Definition

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: ceph-claim
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

As mentioned above for PVs, the accessModes do not enforce access right, but rather act as labels to match a PV to a PVC.

This claim will look for PVs offering 2Gi or greater capacity.

Save the PVC definition to a file, for example ceph-claim.yaml, and create the PVC:

# oc create -f ceph-claim.yaml
persistentvolumeclaim "ceph-claim" created

#and verify the PVC was created and bound to the expected PV:
# oc get pvc
NAME         LABELS    STATUS    VOLUME    CAPACITY   ACCESSMODES   AGE
ceph-claim   <none>    Bound     ceph-pv   1Gi        RWX           21s

the claim was bound to the ceph-pv PV.

Creating the Pod

A pod definition file or a template file can be used to define a pod. Below is a pod specification that creates a single container and mounts the Ceph RBD volume for read-write access:

Example 20.8. Pod Object Definition

apiVersion: v1
kind: Pod
metadata:
  name: ceph-pod1
spec:
  containers:
  - name: ceph-busybox
    image: busybox
    command: ["sleep", "60000"]
    volumeMounts:
    - name: ceph-vol1
      mountPath: /usr/share/busybox
      readOnly: false
  volumes:
  - name: ceph-vol1
    persistentVolumeClaim:
      claimName: ceph-claim

The name of this pod as displayed by oc get pod.

The image run by this pod. In this case, we are telling busybox to sleep.

The name of the volume. This name must be the same in both the containers and volumes sections.

The mount path as seen in the container.

The PVC that is bound to the Ceph RBD cluster.

Save the pod definition to a file, for example ceph-pod1.yaml, and create the pod:

# oc create -f ceph-pod1.yaml
pod "ceph-pod1" created

#verify pod was created
# oc get pod
NAME        READY     STATUS    RESTARTS   AGE
ceph-pod1   1/1       Running   0          2m

After a minute or so, the pod will be in the Running state.

Defining Group and Owner IDs (Optional)

When using block storage, such as Ceph RBD, the physical block storage is managed by the pod. The group ID defined in the pod becomes the group ID of both the Ceph RBD mount inside the container, and the group ID of the actual storage itself. Thus, it is usually unnecessary to define a group ID in the pod specifiation. However, if a group ID is desired, it can be defined using fsGroup, as shown in the following pod definition fragment:

Example 20.9. Group ID Pod Definition

...
spec:
  containers:
    - name:
    ...
  securityContext:
    fsGroup: 7777
...

securityContext must be defined at the pod level, not under a specific container.

All containers in the pod will have the same fsGroup ID.

Complete Example Using GlusterFS

Overview

This topic provides an end-to-end example of how to use an existing Gluster cluster as an OpenShift Container Platform persistent store. It is assumed that a working Gluster cluster is already set up. If not, consult the Red Hat Gluster Storage Administration Guide.

Persistent Storage Using GlusterFS provides an explanation of persistent volumes (PVs), persistent volume claims (PVCs), and using GlusterFS as persistent storage.

Note

All oc …​ commands are executed on the OpenShift Container Platform master host.

Installing the glusterfs-fuse Package

The glusterfs-fuse library must be installed on all schedulable OpenShift Container Platform nodes:

# yum install -y glusterfs-fuse

Note

The OpenShift Container Platform all-in-one host is often not used to run pod workloads and, thus, is not included as a schedulable node.

Creating the Gluster Endpoints and Gluster Service for Persistence

The named endpoints define each node in the Gluster-trusted storage pool:

Example 20.10. GlusterFS Endpoint Definition

apiVersion: v1
kind: Endpoints
metadata:
  name: gluster-cluster
subsets:
- addresses:
  - ip: 192.168.122.21
  ports:
  - port: 1
    protocol: TCP
- addresses:
  - ip: 192.168.122.22
  ports:
  - port: 1
    protocol: TCP

The endpoints name. If using a service, then the endpoints name must match the service name.

An array of IP addresses for each node in the Gluster pool. Currently, host names are not supported.

The port numbers are ignored, but must be legal port numbers. The value 1 is commonly used.

Save the endpoints definition to a file, for example gluster-endpoints.yaml, then create the endpoints object:

# oc create -f gluster-endpoints.yaml
endpoints "gluster-cluster" created

Verify that the endpoints were created:

# oc get endpoints gluster-cluster
NAME                ENDPOINTS                           AGE
gluster-cluster     192.168.122.21:1,192.168.122.22:1   1m

Note

To persist the Gluster endpoints, you also need to create a service.

Note

Endpoints are name-spaced. Each project accessing the Gluster volume needs its own endpoints.

Example 20.11. GlusterFS Service Definition

apiVersion: v1
kind: Service
metadata:
  name: gluster-cluster
spec:
  ports:
  - port: 1

The name of the service. If using a service, then the endpoints name must match the service name.

The port should match the same port used in the endpoints.

Save the service definition to a file, for example gluster-service.yaml, then create the endpoints object:

# oc create -f gluster-service.yaml
endpoints "gluster-cluster" created

Verify that the service was created:

# oc get service gluster-cluster
NAME                CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
gluster-cluster     10.0.0.130   <none>        1/TCP     9s

Creating the Persistent Volume

Next, before creating the PV object, define the persistent volume in OpenShift Container Platform:

Example 20.12. Persistent Volume Object Definition Using GlusterFS

apiVersion: v1
kind: PersistentVolume
metadata:
  name: gluster-pv
spec:
  capacity:
    storage: 1Gi
  accessModes:
  - ReadWriteMany
  glusterfs:
    endpoints: gluster-cluster
    path: /HadoopVol
    readOnly: false
  persistentVolumeReclaimPolicy: Retain

The name of the PV, which is referenced in pod definitions or displayed in various oc volume commands.

The amount of storage allocated to this volume.

accessModes are used as labels to match a PV and a PVC. They currently do not define any form of access control.

This defines the volume type being used. In this case, the glusterfs plug-in is defined.

This references the endpoints named above.

This is the Gluster volume name, preceded by /.

A volume reclaim policy of retain indicates that the volume will be preserved after the pods accessing it terminate. Accepted values include Retain, Delete, and Recycle.

Save the PV definition to a file, for example gluster-pv.yaml, and create the persistent volume:

# oc create -f gluster-pv.yaml
persistentvolume "gluster-pv" created

Verify that the persistent volume was created:

# oc get pv
NAME         LABELS    CAPACITY   ACCESSMODES   STATUS      CLAIM     REASON    AGE
gluster-pv   <none>    1Gi        RWX           Available                       37s

Creating the Persistent Volume Claim

A persistent volume claim (PVC) specifies the desired access mode and storage capacity. Currently, based on only these two attributes, a PVC is bound to a single PV. Once a PV is bound to a PVC, that PV is essentially tied to the PVC’s project and cannot be bound to by another PVC. There is a one-to-one mapping of PVs and PVCs. However, multiple pods in the same project can use the same PVC.

Example 20.13. PVC Object Definition

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: gluster-claim
spec:
  accessModes:
  - ReadWriteMany
  resources:
     requests:
       storage: 1Gi

The claim name is referenced by the pod under its volumes section.

As mentioned above for PVs, the accessModes do not enforce access rights, but rather act as labels to match a PV to a PVC.

This claim will look for PVs offering 1Gi or greater capacity.

Save the PVC definition to a file, for example gluster-claim.yaml, and create the PVC:

# oc create -f gluster-claim.yaml
persistentvolumeclaim "gluster-claim" created

Verify the PVC was created and bound to the expected PV:

# oc get pvc
NAME            LABELS    STATUS    VOLUME       CAPACITY   ACCESSMODES   AGE
gluster-claim   <none>    Bound     gluster-pv   1Gi        RWX           24s

The claim was bound to the gluster-pv PV.

Defining GlusterFS Volume Access

Access is necessary to a node in the Gluster-trusted storage pool. On this node, examine the glusterfs-fuse mount:

# ls -lZ /mnt/glusterfs/
drwxrwx---. yarn hadoop system_u:object_r:fusefs_t:s0    HadoopVol

# id yarn
uid=592(yarn) gid=590(hadoop) groups=590(hadoop)

The owner has ID 592.

The group has ID 590.

In order to access the HadoopVol volume, the container must match the SELinux label, and either run with a UID of 592, or with 590 in its supplemental groups. It is recommended to gain access to the volume by matching the Gluster mount’s groups, which is defined in the pod definition below.

By default, SELinux does not allow writing from a pod to a remote Gluster server. To enable writing to GlusterFS volumes with SELinux enforcing on each node, run:

# setsebool -P virt_sandbox_use_fusefs on

Note

The virt_sandbox_use_fusefs boolean is defined by the docker-selinux package. If you get an error saying it is not defined, ensure that this package is installed.

Creating the Pod using NGINX Web Server image

A pod definition file or a template file can be used to define a pod. Below is a pod specification that creates a single container and mounts the Gluster volume for read-write access:

Note

The NGINX image may require to run in privileged mode to create the mount and run properly. An easy way to accomplish this is to simply add your user to the privileged Security Context Constraint (SCC):

$ oadm policy add-scc-to-user privileged myuser

Then, add the privileged: true to the containers securityContext: section of the YAML file (as seen in the example below).

Managing Security Context Constraints provides additional information regarding SCCs.

Example 20.14. Pod Object Definition using NGINX image

apiVersion: v1
kind: Pod
metadata:
  name: gluster-pod1
  labels:
    name: gluster-pod1
spec:
  containers:
  - name: gluster-pod1
    image: nginx
    ports:
    - name: web
      containerPort: 80
    securityContext:
      privileged: true
    volumeMounts:
    - name: gluster-vol1
      mountPath: /usr/share/nginx/html
      readOnly: false
  securityContext:
    supplementalGroups: [590]
  volumes:
  - name: gluster-vol1
    persistentVolumeClaim:
      claimName: gluster-claim

The name of this pod as displayed by oc get pod.

The image run by this pod. In this case, we are using a standard NGINX image.

The name of the volume. This name must be the same in both the containers and volumes sections.

The mount path as seen in the container.

The SupplementalGroup ID (Linux Groups) to be assigned at the pod level and as discussed this should match the POSIX permissions on the Gluster volume.

The PVC that is bound to the Gluster cluster.

Save the pod definition to a file, for example gluster-pod1.yaml, and create the pod:

# oc create -f gluster-pod1.yaml
pod "gluster-pod1" created

Verify the pod was created:

# oc get pod
NAME           READY     STATUS    RESTARTS   AGE
gluster-pod1   1/1       Running   0          31s

After a minute or so, the pod will be in the Running state.

More details are shown in the oc describe pod command:

# oc describe pod gluster-pod1
Name:			gluster-pod1
Namespace:		default
Security Policy:	privileged
Node:			ose1.rhs/192.168.122.251
Start Time:		Wed, 24 Aug 2016 12:37:45 -0400
Labels:			name=gluster-pod1
Status:			Running
IP:			172.17.0.2
Controllers:		<none>
Containers:
  gluster-pod1:
    Container ID:	docker://e67ed01729e1dc7369c5112d07531a27a7a02a7eb942f17d1c5fce32d8c31a2d
    Image:		nginx
    Image ID:		docker://sha256:4efb2fcdb1ab05fb03c9435234343c1cc65289eeb016be86193e88d3a5d84f6b
    Port:		80/TCP
    State:		Running
      Started:		Wed, 24 Aug 2016 12:37:52 -0400
    Ready:		True
    Restart Count:	0
    Volume Mounts:
      /usr/share/nginx/html/test from glustervol (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from default-token-1n70u (ro)
    Environment Variables:	<none>
Conditions:
  Type		Status
  Initialized 	True
  Ready 	True
  PodScheduled 	True
Volumes:
  glustervol:
    Type:	PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
    ClaimName:	gluster-claim
    ReadOnly:	false
  default-token-1n70u:
    Type:	Secret (a volume populated by a Secret)
    SecretName:	default-token-1n70u
QoS Tier:	BestEffort
Events:
  FirstSeen	LastSeen	Count	From			SubobjectPath			Type		Reason		Message
  ---------	--------	-----	----			-------------			--------	------		-------
  10s		10s		1	{default-scheduler }					Normal		Scheduled	Successfully assigned gluster-pod1 to ose1.rhs
  9s		9s		1	{kubelet ose1.rhs}	spec.containers{gluster-pod1}	Normal		Pulling		pulling image "nginx"
  4s		4s		1	{kubelet ose1.rhs}	spec.containers{gluster-pod1}	Normal		Pulled		Successfully pulled image "nginx"
  3s		3s		1	{kubelet ose1.rhs}	spec.containers{gluster-pod1}	Normal		Created		Created container with docker id e67ed01729e1
  3s		3s		1	{kubelet ose1.rhs}	spec.containers{gluster-pod1}	Normal		Started		Started container with docker id e67ed01729e1

The project (namespace) name.

The IP address of the OpenShift Container Platform node running the pod.

The PVC name used by the pod.

The list of events resulting in the pod being launched and the Gluster volume being mounted.

There is more internal information, including the SCC used to authorize the pod, the pod’s user and group IDs, the ⁠SELinux label, and more shown in the oc get pod <name> -o yaml command:

# oc get pod gluster-pod1 -o yaml
apiVersion: v1
kind: Pod
metadata:
  annotations:
    openshift.io/scc: privileged
  creationTimestamp: 2016-08-24T16:37:45Z
  labels:
    name: gluster-pod1
  name: gluster-pod1
  namespace: default
  resourceVersion: "482"
  selfLink: /api/v1/namespaces/default/pods/gluster-pod1
  uid: 15afda77-6a19-11e6-aadb-525400f7256d
spec:
  containers:
  - image: nginx
    imagePullPolicy: Always
    name: gluster-pod1
    ports:
    - containerPort: 80
      name: web
      protocol: TCP
    resources: {}
    securityContext:
      privileged: true
    terminationMessagePath: /dev/termination-log
    volumeMounts:
    - mountPath: /usr/share/nginx/html
      name: glustervol
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: default-token-1n70u
      readOnly: true
  dnsPolicy: ClusterFirst
  host: ose1.rhs
  imagePullSecrets:
  - name: default-dockercfg-20xg9
  nodeName: ose1.rhs
  restartPolicy: Always
  securityContext:
    supplementalGroups:
    - 590
  serviceAccount: default
  serviceAccountName: default
  terminationGracePeriodSeconds: 30
  volumes:
  - name: glustervol
    persistentVolumeClaim:
      claimName: gluster-claim
  - name: default-token-1n70u
    secret:
      secretName: default-token-1n70u
status:
  conditions:
  - lastProbeTime: null
    lastTransitionTime: 2016-08-24T16:37:45Z
    status: "True"
    type: Initialized
  - lastProbeTime: null
    lastTransitionTime: 2016-08-24T16:37:53Z
    status: "True"
    type: Ready
  - lastProbeTime: null
    lastTransitionTime: 2016-08-24T16:37:45Z
    status: "True"
    type: PodScheduled
  containerStatuses:
  - containerID: docker://e67ed01729e1dc7369c5112d07531a27a7a02a7eb942f17d1c5fce32d8c31a2d
    image: nginx
    imageID: docker://sha256:4efb2fcdb1ab05fb03c9435234343c1cc65289eeb016be86193e88d3a5d84f6b
    lastState: {}
    name: gluster-pod1
    ready: true
    restartCount: 0
    state:
      running:
        startedAt: 2016-08-24T16:37:52Z
  hostIP: 192.168.122.251
  phase: Running
  podIP: 172.17.0.2
  startTime: 2016-08-24T16:37:45Z

The SCC used by the pod.

The project (namespace) name.

The security context level requested, in this case privileged

The supplemental group ID for the pod (all containers).

The PVC name used by the pod.

Backing Docker Registry with GlusterFS Storage

Overview

This topic reviews how to attach a GlusterFS persistent volume to the Docker Registry.

It is assumed that the Docker registry service has already been started and the Gluster volume has been created.

Prerequisites

The docker-registry was deployed without configuring storage.

A Gluster volume exists and glusterfs-fuse is installed on schedulable nodes.

Definitions written for GlusterFS endpoints and service, persistent volume (PV), and persistent volume claim (PVC).

For this guide, these will be:

gluster-endpoints-service.yaml

gluster-endpoints.yaml

gluster-pv.yaml

gluster-pvc.yaml

A user with the cluster-admin role binding.

For this guide, that user is admin.

Note

All oc commands are executed on the master node as the admin user.

Create the Gluster Persistent Volume

First, make the Gluster volume available to the registry.

$ oc create -f gluster-endpoints-service.yaml
$ oc create -f gluster-endpoints.yaml
$ oc create -f gluster-pv.yaml
$ oc create -f gluster-pvc.yaml

Check to make sure the PV and PVC were created and bound successfully. The expected output should resemble the following. Note that the PVC status is Bound, indicating that it has bound to the PV.

$ oc get pv
NAME         LABELS    CAPACITY   ACCESSMODES   STATUS      CLAIM     REASON    AGE
gluster-pv   <none>    1Gi        RWX           Available                       37s
$ oc get pvc
NAME            LABELS    STATUS    VOLUME       CAPACITY   ACCESSMODES   AGE
gluster-claim   <none>    Bound     gluster-pv   1Gi        RWX           24s

Note

If either the PVC or PV failed to create or the PVC failed to bind, refer back to the GlusterFS Persistent Storage guide. Do not proceed until they initialize and the PVC status is Bound.

Attach the PVC to the Docker Registry

Before moving forward, ensure that the docker-registry service is running.

$ oc get svc
NAME              CLUSTER_IP       EXTERNAL_IP   PORT(S)                 SELECTOR                  AGE
docker-registry   172.30.167.194   <none>        5000/TCP                docker-registry=default   18m

Note

If either the docker-registry service or its associated pod is not running, refer back to the docker-registry setup instructions for troubleshooting before continuing.

Then, attach the PVC:

$ oc volume deploymentconfigs/docker-registry --add --name=v1 -t pvc \
     --claim-name=gluster-claim --overwrite

Deploying a Docker Registry provides more information on using the Docker registry.

Known Issues

Pod Cannot Resolve the Volume Host

In non-production cases where the dnsmasq server is located on the same node as the OpenShift Container Platform master service, pods might not resolve to the host machines when mounting the volume, causing errors in the docker-registry-1-deploy pod. This can happen when dnsmasq.service fails to start because of a collision with OpenShift Container Platform DNS on port 53. To run the DNS server on the master host, some configurations needs to be changed.

In /etc/dnsmasq.conf, add:

# Reverse DNS record for master
host-record=master.example.com,<master-IP>
# Wildcard DNS for OpenShift Applications - Points to Router
address=/apps.example.com/<master-IP>
# Forward .local queries to SkyDNS
server=/local/127.0.0.1#8053
# Forward reverse queries for service network to SkyDNS.
# This is for default OpenShift SDN - change as needed.
server=/17.30.172.in-addr.arpa/127.0.0.1#8053

With these settings, dnsmasq will pull from the /etc/hosts file on the master node.

Add the appropriate host names and IPs for all necessary hosts.

In master-config.yaml, change bindAddress to:

dnsConfig:
 bindAddress: 127.0.0.1:8053

When pods are created, they receive a copy of /etc/resolv.conf, which typically contains only the master DNS server so they can resolve external DNS requests. To enable internal DNS resolution, insert the dnsmasq server at the top of the server list. This way, dnsmasq will attempt to resolve requests internally first.

In /etc/resolv.conf all scheduled nodes:

nameserver 192.168.1.100
nameserver 192.168.1.1

Add the internal DNS server.

Pre-existing external DNS server.

Once the configurations are changed, restart the OpenShift Container Platform master and dnsmasq services.

$ systemctl restart atomic-openshift-master
$ systemctl restart dnsmasq

Binding Persistent Volumes by Labels

Overview

This topic provides an end-to-end example for binding persistent volume claims (PVCs) to persistent volumes (PVs), by defining labels in the PV and matching selectors in the PVC. This feature is available for all storage options. It is assumed that a OpenShift Container Platform cluster contains persistent storage resources which are available for binding by PVCs.

A Note on Labels and Selectors

Labels are an OpenShift Container Platform feature that support user-defined tags (key-value pairs) as part of an object’s specification. Their primary purpose is to enable the arbitrary grouping of objects by defining identical labels among them. These labels can then be targeted by selectors to match all objects with specified label values. It is this functionality we will take advantage of to enable our PVC to bind to our PV. For a more in-depth look at labels, see Pods and Services.

Note

For this example, we will be using modified GlusterFS PV and PVC specifications. However, implementation of selectors and labels is generic across for all storage options. See the relevant storage option for your volume provider to learn more about its unique configuration.

Assumptions

It is assumed that you have:

An existing OpenShift Container Platform cluster with at least one master and one node

At least one supported storage volume

A user with cluster-admin privileges

Defining Specifications

Note

These specifications are tailored to GlusterFS. Consult the relevant storage option for your volume provider to learn more about its unique configuration.

Persistent Volume with Labels

Example 20.15. glusterfs-pv.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: gluster-volume
  labels:
    storage-tier: gold
    aws-availability-zone: us-east-1
spec:
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteMany
  glusterfs:
    endpoints: glusterfs-cluster
    path: myVol1
    readOnly: false
  persistentVolumeReclaimPolicy: Retain

Use labels to identify common attributes or characteristics shared among volumes. In this case, we defined the Gluster volume to have a custom attribute (key) named storage-tier with a value of gold assigned. A claim will be able to select a PV with storage-tier=gold to match this PV.

Endpoints define the Gluster trusted pool and are discussed below.

Persistent Volume Claim with Selectors

A claim with a selector stanza (see example below) attempts to match existing, unclaimed, and non-prebound PVs. The existence of a PVC selector ignores a PV’s capacity. However, accessModes are still considered in the matching criteria.

It is important to note that a claim must match all of the key-value pairs included in its selector stanza. If no PV matches the claim, then the PVC will remain unbound (Pending). A PV can subsequently be created and the claim will automatically check for a label match.

Example 20.16. glusterfs-pvc.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: gluster-claim
spec:
  accessModes:
  - ReadWriteMany
  resources:
     requests:
       storage: 1Gi
  selector:
    matchLabels:
      storage-tier: gold
      aws-availability-zone: us-east-1

The selector stanza defines all labels necessary in a PV in order to match this claim.

Volume Endpoints

To attach the PV to the Gluster volume, endpoints should be configured before creating our objects.

Example 20.17. glusterfs-ep.yaml

  apiVersion: v1
  kind: Endpoints
  metadata:
    name: glusterfs-cluster
  subsets:
    - addresses:
        - ip: 192.168.122.221
      ports:
        - port: 1
    - addresses:
        - ip: 192.168.122.222
      ports:
        - port: 1

Deploy the PV, PVC, and Endpoints

For this example, run the oc commands as a cluster-admin privileged user. In a production environment, cluster clients might be expected to define and create the PVC.

# oc create -f glusterfs-ep.yaml
endpoints "glusterfs-cluster" created
# oc create -f glusterfs-pv.yaml
persistentvolume "gluster-volume" created
# oc create -f glusterfs-pvc.yaml
persistentvolume "gluster-volume" created

Lastly, confirm that the PV and PVC bound successfully.

# oc get pv,pvc
NAME              CAPACITY   ACCESSMODES      STATUS     CLAIM                     REASON    AGE
gluster-volume    2Gi        RWX              Bound      gfs-trial/gluster-claim             7s
NAME              STATUS     VOLUME           CAPACITY   ACCESSMODES               AGE
gluster-claim     Bound      gluster-volume   2Gi        RWX                       7s

Note

PVCs are local to a project, whereas PVs are a cluster-wide, global resource. Developers and non-administrator users may not have access to see all (or any) of the available PVs.

Chapter 21. Working with HTTP Proxies

Overview

Production environments can deny direct access to the Internet and instead have an HTTP or HTTPS proxy available. Configuring OpenShift Container Platform to use these proxies can be as simple as setting standard environment variables in configuration or JSON files. This can be done during an advanced installation or configured after installation.

The proxy configuration must be the same on each host in the cluster. Therefore, when setting up the proxy or modifying it, you must update the files on each OpenShift Container Platform host to the same values. Then, you must restart OpenShift Container Platform services on each host in the cluster.

The NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables are found in each host’s /etc/sysconfig/atomic-openshift-master file (for single master configuration), /etc/sysconfig/atomic-openshift-master-api, or /etc/sysconfig/atomic-openshift-master-controllers files (for multi-master configuration) and /etc/sysconfig/atomic-openshift-node.

Configuring NO_PROXY

The NO_PROXY environment variable lists all of the OpenShift Container Platform components and all IP addresses that are managed by OpenShift Container Platform.

NO_PROXY accepts a comma-separated list of hosts, IP addresses, or IP ranges in CIDR format:

For master hosts

Node host name

Master IP or host name

For node hosts

Master IP or host name

For the Docker service

Registry service IP and host name

NO_PROXY also includes the SDN network and service IP addresses as found in the master-config.yaml file.

/etc/origin/master/master-config.yaml

networkConfig:
  clusterNetworkCIDR: 10.1.0.0/16
  serviceNetworkCIDR: 172.30.0.0/16

OpenShift Container Platform does not accept * as a wildcard attached to a domain suffix. For example, this works:

NO_PROXY=.example.com

However, this does not:

NO_PROXY=*.example.com

The only wildcard NO_PROXY accepts is a single * character, which matches all hosts, and effectively disables the proxy.

Each name in this list is matched as either a domain which contains the host name as a suffix, or the host name itself.

For instance, example.com would match example.com, example.com:80, and www.example.com.

Configuring Hosts for Proxies

Edit the proxy environment variables in the OpenShift Container Platform control files. Ensure all of the files in the cluster are correct.

HTTP_PROXY=http://<user>:<password>@<ip_addr>:<port>/
HTTPS_PROXY=https://<user>:<password>@<ip_addr>:<port>/
NO_PROXY=master.hostname.example.com,10.1.0.0/16,172.30.0.0/16

Supports host names and CIDRs. Must include the SDN network and service IP ranges 10.1.0.0/16,172.30.0.0/16 by default.

Restart the master or node host as appropriate:

# systemctl restart atomic-openshift-master
# systemctl restart atomic-openshift-node

For multi-master installations:

# systemctl restart atomic-openshift-master-controllers
# systemctl restart atomic-openshift-master-api

Configuring Hosts for Proxies Using Ansible

During advanced installations, the NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables can be configured using the openshift_no_proxy, openshift_http_proxy, and openshift_https_proxy parameters, which are configurable in the inventory file.

Example 21.1. Example Proxy Configuration with Ansible

# Global Proxy Configuration
# These options configure HTTP_PROXY, HTTPS_PROXY, and NOPROXY environment
# variables for docker and master services.
openshift_http_proxy=http://<user>:<password>@<ip_addr>:<port>
openshift_https_proxy=https://<user>:<password>@<ip_addr>:<port>
openshift_no_proxy='.hosts.example.com,some-host.com'
#
# Most environments do not require a proxy between OpenShift masters, nodes, and
# etcd hosts. So automatically add those host names to the openshift_no_proxy list.
# If all of your hosts share a common domain you may wish to disable this and
# specify that domain above.
# openshift_generate_no_proxy_hosts=True

Note

There are additional proxy settings that can be configured for builds using Ansible parameters. For example:

The openshift_builddefaults_git_http_proxy and openshift_builddefaults_git_https_proxy parameters allow you to use a proxy for Git cloning

The openshift_builddefaults_http_proxy and openshift_builddefaults_https_proxy parameters can make environment variables available to the Docker build strategy and Custom build strategy processes.

Proxying Docker Pull

OpenShift Container Platform node hosts need to perform push and pull operations to Docker registries. If you have a registry that does not need a proxy for nodes to access, include the NO_PROXY parameter with:

the registry’s host name,

the registry service’s IP address, and

the service name.

This blacklists that registry, leaving the external HTTP proxy as the only option.

Retrieve the registry service’s IP address docker_registy_ip by running:

$ oc describe svc/docker-registry -n default

Name:			docker-registry
Namespace:		default
Labels:			docker-registry=default
Selector:		docker-registry=default
Type:			ClusterIP
IP:			172.30.163.183
Port:			5000-tcp	5000/TCP
Endpoints:		10.1.0.40:5000
Session Affinity:	ClientIP
No events.

Registry service IP.

Edit the /etc/sysconfig/docker file and add the NO_PROXY variables in shell format, replacing <docker_registry_ip> with the IP address from the previous step.

HTTP_PROXY=http://<user>:<password>@<ip_addr>:<port>/
HTTPS_PROXY=https://<user>:<password>@<ip_addr>:<port>/
NO_PROXY=master.hostname.example.com,<docker_registry_ip>,docker-registry.default.svc.cluster.local

Restart the Docker service:

# systemctl restart docker

Configuring S2I Builds for Proxies

S2I builds fetch dependencies from various locations. You can use a .s2i/environment file to specify simple shell variables and OpenShift Container Platform will react accordingly when seeing build images.

The following are the supported proxy environment variables with example values:

HTTP_PROXY=http://USERNAME:PASSWORD@10.0.1.1:8080/
HTTPS_PROXY=https://USERNAME:PASSWORD@10.0.0.1:8080/
NO_PROXY=master.hostname.example.com

Configuring Default Templates for Proxies

The example templates available in OpenShift Container Platform by default do not include settings for HTTP proxies. For existing applications based on these templates, modify the source section of the application’s build configuration and add proxy settings:

...
source:
  type: Git
  git:
    uri: https://github.com/openshift/ruby-hello-world
    httpProxy: http://proxy.example.com
    httpsProxy: https://proxy.example.com
...

This is similar to the process for using proxies for Git cloning.

Setting Proxy Environment Variables in Pods

You can set the NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables in the templates.spec.containers stanza in a deployment configuration to pass proxy connection information. The same can be done for configuring a Pod’s proxy at runtime:

...
containers:
- env:
  - name: "HTTP_PROXY"
    value: "http://<user>:<password>@<ip_addr>:<port>"
...

You can also use the oc set env command to update an existing deployment configuration with a new environment variable:

$ oc set env dc/frontend HTTP_PROXY=http://<user>:<password>@<ip_addr>:<port>

If you have a ConfigChange trigger set up in your OpenShift Container Platform instance, the changes happen automatically. Otherwise, manually redeploy your application for the changes to take effect.

Git Repository Access

If your Git repository can only be accessed using a proxy, you can define the proxy to use in the source section of the BuildConfig. You can configure both a HTTP and HTTPS proxy to use. Both fields are optional. Domains for which no proxying should be performed can also be specified via the NoProxy field.

Note

Your source URI must use the HTTP or HTTPS protocol for this to work.

source:
  type: Git
  git:
    uri: "https://github.com/openshift/ruby-hello-world"
    httpProxy: http://proxy.example.com
    httpsProxy: https://proxy.example.com
    noProxy: somedomain.com, otherdomain.com

Cluster administrators can also configure a global proxy for Git cloning using Ansible.

Chapter 22. Configuring Global Build Defaults and Overrides

Overview

Developers can define settings in specific build configurations within their projects, such as configuring a proxy for Git cloning. Rather than requiring developers to define certain settings in each of their build configurations, cluster administrators can use admission control plug-ins to configure global build defaults and overrides that automatically use these settings in any build.

The settings from these plug-ins are not set in the build configurations or builds themselves, but rather are only used during the build process. This allows administrators to change the global configuration at any time, and any builds that are re-run from existing build configurations or builds will get the new settings.

The BuildDefaults admission control plug-in allows administrators to set global defaults for settings such as the Git HTTP and HTTPS proxy, as well as default environment variables. These defaults do not overwrite values that have been configured for a specific build. However, if those values are not present on the build definition, they are set to the default value.

The BuildOverrides admission control plug-in allows administrators to override a setting in a build, regardless of the value stored in the build. It currently supports overriding the forcePull flag on a build strategy to enforce always refreshing the local image during a build by pulling the image from the registry. This ensures that a user can only build with an image that they are allowed to pull.

Setting Global Build Defaults

You can set global build defaults two ways:

using Ansible and the advanced installation tool

manually by modifying the master-config.yaml file

Configuring Global Build Defaults with Ansible

During advanced installations, the BuildDefaults plug-in can be configured using the following parameters, which are configurable in the inventory file:

openshift_builddefaults_http_proxy

openshift_builddefaults_https_proxy

openshift_builddefaults_no_proxy

openshift_builddefaults_git_http_proxy

openshift_builddefaults_git_https_proxy

Example 22.1. Example Build Defaults Configuration with Ansible

# These options configure the BuildDefaults admission controller which injects
# environment variables into Builds. These values will default to the global proxy
# config values. You only need to set these if they differ from the global settings
# above. See BuildDefaults
# documentation at https://docs.openshift.org/latest/admin_guide/build_defaults_overrides.html
#openshift_builddefaults_http_proxy=http://USER:PASSWORD@HOST:PORT
openshift_builddefaults_https_proxy=https://USER:PASSWORD@HOST:PORT
openshift_builddefaults_no_proxy=build_defaults
openshift_builddefaults_git_http_proxy=http://USER:PASSWORD@HOST:PORT
openshift_builddefaults_git_https_proxy=https://USER:PASSWORD@HOST:PORT
# Or you may optionally define your own serialized as json
#openshift_builddefaults_json='{"BuildDefaults":{"configuration":{"apiVersion":"v1","env":[{"name":"HTTP_PROXY","value":"http://proxy.example.com.redhat.com:3128"},{"name":"NO_PROXY","value":"ose3-master.example.com"}],"gitHTTPProxy":"http://proxy.example.com:3128","kind":"BuildDefaultsConfig"}}}'

Note

There are additional proxy settings that can be configured for builds using Ansible parameters. For example: - The openshift_builddefaults_git_http_proxy and openshift_builddefaults_git_https_proxy parameters allow you to use a proxy for git cloning - The openshift_builddefaults_http_proxy and openshift_builddefaults_https_proxy parameters can make environment variables available to the Docker build strategy and Custom build strategy processes.

Manually Setting Global Build Defaults

To configure the BuildDefaults plug-in, add a configuration for it in the /etc/origin/master/master-config.yaml file on masters:

admissionConfig:
  pluginConfig:
    BuildDefaults:
      configuration:
        apiVersion: v1
        kind: BuildDefaultsConfig
        gitHTTPProxy: http://my.proxy:8080
        gitHTTPSProxy: https://my.proxy:8443
        gitNoProxy: somedomain.com, otherdomain.com
        env:
        - name: HTTP_PROXY
          value: http://my.proxy:8080
        - name: HTTPS_PROXY
          value: https://my.proxy:8443
        - name: BUILD_LOGLEVEL
          value: 4
        - name: CUSTOM_VAR
          value: custom_value
        imageLabels:
        - name: url
          value: https://containers.example.org
        - name: vendor
          value: ExampleCorp Ltd.
        nodeSelector:
          key1: value1
          key2: value2
        annotations:
          key1: value1
          key2: value2
        resources:
          requests:
            cpu: "100m"
            memory: "256Mi"
          limits:
            cpu: "100m"
            memory: "256Mi"

Sets the HTTP proxy to use when cloning source code from a Git repository.

Sets the HTTPS proxy to use when cloning source code from a Git repository.

Sets the list of domains for which proxying should not be performed.

Default environment variable that sets the HTTP proxy to use during the build. This can be used for downloading dependencies during the assemble and build phases.

Default environment variable that sets the HTTPS proxy to use during the build. This can be used for downloading dependencies during the assemble and build phases.

Default environment variable that sets the build log level during the build.

Additional default environment variable that will be added to every build.

Labels to be applied to every image built. These can be overridden in BuildConfig.

Build pods will only run on nodes with the key1=value2 and key2=value2 labels. Users can define a different set of nodeSelectors for their builds, causing these values to be ignored.

Build pods will have these annotations added to them.

Sets the default resources to the build pod if the BuildConfig does not have related resource defined.

Restart the master service for the changes to take effect:

# systemctl restart atomic-openshift-master

Setting Global Build Overrides

To configure the BuildOverrides plug-in, add a configuration for it in the /etc/origin/master/master-config.yaml file on masters:

kubernetesMasterConfig:
  admissionConfig:
    pluginConfig:
      BuildOverrides:
        configuration:
          apiVersion: v1
          kind: BuildOverridesConfig
          forcePull: true

Force all builds to pull their builder image and any source images before starting the build.

Restart the master service for the changes to take effect:

# systemctl restart atomic-openshift-master

Chapter 23. Configuring Pipeline Execution

Overview

The first time a user creates a build configuration using the Pipeline build strategy, OpenShift Container Platform looks for the a template named jenkins-ephemeral in the openshift namespace and instantiates it within the user’s project. The jenkins-ephemeral template that ships with OpenShift Container Platform creates, upon instantiation:

a deployment configuration for Jenkins using the official OpenShift Container Platform Jenkins image

a service and route for accessing the Jenkins deployment

a new Jenkins service account

rolebindings to grant the service account edit access to the project

Cluster administrators can control what is created by either modifying the content of the built-in template, or by editing the cluster configuration to direct the cluster to a different template location.

To modify the content of the default template:

$ oc edit template jenkins-ephemeral -n openshift

To use a different template, such as the jenkins-persistent template which uses persistent storage for Jenkins, add the following to your master configuration file:

jenkinsPipelineConfig:
  autoProvisionEnabled: true
  templateNamespace: openshift
  templateName: jenkins-pipeline
  serviceName: jenkins-pipeline-svc
  parameters:
    key1: value1
    key2: value2

Defaults to false. If false, then no template will be instantiated.

Namespace containing the template to be instantiated.

Name of the template to be instantiated.

Name of the service to be created by the template upon instantiation.

Optional values to pass to the template during instantiation.

Important

When a Pipeline build configuration is created, OpenShift Container Platform instantiates the jenkinsPipelineConfig template only if no existing service name in the project matches the serviceName field. This means serviceName must be chosen such that it is unique in the project.

Chapter 24. Configuring Routing

Overview

After installing OpenShift Container Platform and deploying a router, you can modify the router to suit your needs using the examples in this topic.

Configuring Route Timeouts

You can configure the default timeouts for an existing route when you have services in need of a low timeout, as required for Service Level Availability (SLA) purposes, or a high timeout, for cases with a slow back end.

Using the oc annotate command, add the timeout to the route:

# oc annotate route <route_name> \
    --overwrite haproxy.router.openshift.io/timeout=<timeout><time_unit>

For example, to set a route named myroute to a timeout of two seconds:

# oc annotate route myroute --overwrite haproxy.router.opensfhit.io/timeout=2s

Supported time units are microseconds (us), milliseconds (ms), seconds (s), minutes (m), hours (h), or days (d).

Configuring Native Container Routing

This section describes how to set up container networking using existing switches and routers and the kernel networking stack in Linux. The setup requires that the network administrator or a script modifies the router or routers when new nodes are added to the cluster.

Note

The procedure outlined in this topic can be adapted to any type of router.

Network Overview

The following describes a general network setup:

11.11.0.0/16 is the container network.

The 11.11.x.0/24 subnet is reserved for each node and assigned to the Docker Linux bridge.

Each node has a route to the router for reaching anything in the 11.11.0.0/16 range, except the local subnet.

The router has routes for each node, so it can be directed to the right node.

Existing nodes do not need any changes when new nodes are added, unless the network topology is modified.

IP forwarding is enabled on each node.

The following diagram shows the container networking setup described in this topic. It uses one Linux node with two network interface cards serving as a router, two switches, and three nodes connected to these switches.

Node setup

Assign an unused 11.11.x.0/24 subnet IP address to the Linux bridge on the node:

# brctl addbr lbr0
# ip addr add 11.11.1.1/24 dev lbr0
# ip link set dev lbr0 up

Modify the Docker startup script to use the new bridge. By default, the startup script is the /etc/sysconfig/docker file:

# docker -d -b lbr0 --other-options

Add a route to the router for the 11.11.0.0/16 network:

# ip route add 11.11.0.0/16 via 192.168.2.2 dev p3p1

Enable IP forwarding on the node:

# sysctl -w net.ipv4.ip_forward=1

Router setup

The following procedure assumes a Linux box with multiple NICs is used as a router. Modify the steps as required to use the syntax for a particular router:

Enable IP forwarding on the router:

# sysctl -w net.ipv4.ip_forward=1

Add a route for each node added to the cluster:

# ip route add <node_subnet> via <node_ip_address> dev <interface through which node is L2 accessible>
# ip route add 11.11.1.0/24 via 192.168.2.1 dev p3p1
# ip route add 11.11.2.0/24 via 192.168.3.3 dev p3p2
# ip route add 11.11.3.0/24 via 192.168.3.4 dev p3p2

Chapter 25. Routing from Edge Load Balancers

Overview

Pods inside of an OpenShift Container Platform cluster are only reachable via their IP addresses on the cluster network. An edge load balancer can be used to accept traffic from outside networks and proxy the traffic to pods inside the OpenShift Container Platform cluster. In cases where the load balancer is not part of the cluster network, routing becomes a hurdle as the internal cluster network is not accessible to the edge load balancer.

To solve this problem where the OpenShift Container Platform cluster is using OpenShift SDN as the cluster networking solution, there are two ways to achieve network access to the pods.

Including the Load Balancer in the SDN

If possible, run an OpenShift Container Platform node instance on the load balancer itself that uses OpenShift Container Platform SDN as the networking plug-in. This way, the edge machine gets its own Open vSwitch bridge that the SDN automatically configures to provide access to the pods and nodes that reside in the cluster. The routing table is dynamically configured by the SDN as pods are created and deleted, and thus the routing software is able to reach the pods.

Mark the load balancer machine as an unschedulable node so that no pods end up on the load balancer itself:

$ oadm manage-node <load_balancer_hostname> --schedulable=false

If the load balancer comes packaged as a container, then it is even easier to integrate with OpenShift Container Platform: Simply run the load balancer as a pod with the host port exposed. The pre-packaged HAProxy router in OpenShift Container Platform runs in precisely this fashion.

Establishing a Tunnel Using a Ramp Node

In some cases, the previous solution is not possible. For example, an F5 BIG-IP® host cannot run an OpenShift Container Platform node instance or the OpenShift Container Platform SDN because F5® uses a custom, incompatible Linux kernel and distribution.

Instead, to enable F5 BIG-IP® to reach pods, you can choose an existing node within the cluster network as a ramp node and establish a tunnel between the F5 BIG-IP® host and the designated ramp node. Because it is otherwise an ordinary OpenShift Container Platform node, the ramp node has the necessary configuration to route traffic to any pod on any node in the cluster network. The ramp node thus assumes the role of a gateway through which the F5 BIG-IP® host has access to the entire cluster network.

Following is an example of establishing an ipip tunnel between an F5 BIG-IP® host and a designated ramp node.

On the F5 BIG-IP® host:

Set the following variables:

# F5_IP=10.3.89.66
# RAMP_IP=10.3.89.89
# TUNNEL_IP1=10.3.91.216
# CLUSTER_NETWORK=10.128.0.0/14

The F5_IP and RAMP_IP variables refer to the F5 BIG-IP® host’s and the ramp node’s IP addresses, respectively, on a shared, internal network.

An arbitrary, non-conflicting IP address for the F5® host’s end of the ipip tunnel.

The overlay network CIDR that the OpenShift Container Platform SDN uses to assign addresses to pods.

Delete any old route, self, tunnel and SNAT pool:

# tmsh delete net route $CLUSTER_NETWORK || true
# tmsh delete net self SDN || true
# tmsh delete net tunnels tunnel SDN || true
# tmsh delete ltm snatpool SDN_snatpool || true

Create the new tunnel, self, route and SNAT pool and use the SNAT pool in the virtual servers:

# tmsh create net tunnels tunnel SDN \
    \{ description "OpenShift SDN" local-address \
    $F5_IP profile ipip remote-address $RAMP_IP \}
# tmsh create net self SDN \{ address \
    ${TUNNEL_IP1}/24 allow-service all vlan SDN \}
# tmsh create net route $CLUSTER_NETWORK interface SDN
# tmsh create ltm snatpool SDN_snatpool members add { $TUNNEL_IP1 }
# tmsh modify ltm virtual  ose-vserver source-address-translation { type snat pool SDN_snatpool }
# tmsh modify ltm virtual  https-ose-vserver source-address-translation { type snat pool SDN_snatpool }

On the ramp node:

Set the following variables:

# F5_IP=10.3.89.66
# TUNNEL_IP1=10.3.91.216
# TUNNEL_IP2=10.3.91.217
# CLUSTER_NETWORK=10.128.0.0/1

A second, arbitrary IP address for the ramp node’s end of the ipip tunnel.

The overlay network CIDR that the OpenShift Container Platform SDN uses to assign addresses to pods.

Delete any old tunnel:

# ip tunnel del tun1 || true

Create the ipip tunnel on the ramp node, using a suitable L2-connected interface (e.g., eth0):

# ip tunnel add tun1 mode ipip \
    remote $F5_IP dev eth0
# ip addr add $TUNNEL_IP2 dev tun1
# ip link set tun1 up
# ip route add $TUNNEL_IP1 dev tun1
# ping -c 5 $TUNNEL_IP1

SNAT the tunnel IP with an unused IP from the SDN subnet:

# source /run/openshift-sdn/config.env
# tap1=$(ip -o -4 addr list tun0 | awk '{print $4}' | cut -d/ -f1 | head -n 1)
# subaddr=$(echo ${OPENSHIFT_SDN_TAP1_ADDR:-"$tap1"} | cut -d "." -f 1,2,3)
# export RAMP_SDN_IP=${subaddr}.254

Assign this RAMP_SDN_IP as an additional address to tun0 (the local SDN’s gateway):

# ip addr add ${RAMP_SDN_IP} dev tun0

Modify the OVS rules for SNAT:

# ipflowopts="cookie=0x999,ip"
# arpflowopts="cookie=0x999, table=0, arp"
#
# ovs-ofctl -O OpenFlow13 add-flow br0 \
    "${ipflowopts},nw_src=${TUNNEL_IP1},actions=mod_nw_src:${RAMP_SDN_IP},resubmit(,0)"
# ovs-ofctl -O OpenFlow13 add-flow br0 \
    "${ipflowopts},nw_dst=${RAMP_SDN_IP},actions=mod_nw_dst:${TUNNEL_IP1},resubmit(,0)"
# ovs-ofctl -O OpenFlow13 add-flow br0 \
    "${arpflowopts}, arp_tpa=${RAMP_SDN_IP}, actions=output:2"
# ovs-ofctl -O OpenFlow13 add-flow br0 \
    "${arpflowopts}, priority=200, in_port=2, arp_spa=${RAMP_SDN_IP}, arp_tpa=${CLUSTER_NETWORK}, actions=goto_table:5"
# ovs-ofctl -O OpenFlow13 add-flow br0 \
    "arp, table=5, priority=300, arp_tpa=${RAMP_SDN_IP}, actions=output:2"
# ovs-ofctl -O OpenFlow13 add-flow br0 \
    "ip,table=5,priority=300,nw_dst=${RAMP_SDN_IP},actions=output:2"
# ovs-ofctl -O OpenFlow13 add-flow br0 "${ipflowopts},nw_dst=${TUNNEL_IP1},actions=output:2"

Optionally, if you do not plan on configuring the ramp node to be highly available, mark the ramp node as unschedulable. Skip this step if you do plan to follow the next section and plan on creating a highly available ramp node.

$ oadm manage-node <ramp_node_hostname> --schedulable=false

Note

The F5 router plug-in integrates with F5 BIG-IP®.

Configuring a Highly-Available Ramp Node

You can use OpenShift Container Platform’s ipfailover feature, which uses keepalived internally, to make the ramp node highly available from F5 BIG-IP®'s point of view. To do so, first bring up two nodes, for example called ramp-node-1 and ramp-node-2, on the same L2 subnet.

Then, choose some unassigned IP address from within the same subnet to use for your virtual IP, or VIP. This will be set as the RAMP_IP variable with which you will configure your tunnel on F5 BIG-IP®.

For example, suppose you are using the 10.20.30.0/24 subnet for your ramp nodes, and you have assigned 10.20.30.2 to ramp-node-1 and 10.20.30.3 to ramp-node-2. For your VIP, choose some unassigned address from the same 10.20.30.0/24 subnet, for example 10.20.30.4. Then, to configure ipfailover, mark both nodes with a label, such as f5rampnode:

$ oc label node ramp-node-1 f5rampnode=true
$ oc label node ramp-node-2 f5rampnode=true

Similar to instructions from the ipfailover documentation, you must now create a service account and add it to the privileged SCC. First, create the f5ipfailover service account:

$ oc create serviceaccount f5ipfailover -n default

Next, you can add the f5ipfailover service to the privileged SCC. To add the f5ipfailover in the default namespace to the privileged SCC, run:

$ oadm policy add-scc-to-user privileged system:serviceaccount:default:f5ipfailover

Finally, configure ipfailover using your chosen VIP (the RAMP_IP variable) and the f5ipfailover service account, assigning the VIP to your two nodes using the f5rampnode label you set earlier:

# RAMP_IP=10.20.30.4
# IFNAME=eth0
# oadm ipfailover <name-tag> \
    --virtual-ips=$RAMP_IP \
    --interface=$IFNAME \
    --watch-port=0 \
    --replicas=2 \
    --service-account=f5ipfailover  \
    --selector='f5rampnode=true'

The interface where RAMP_IP should be configured.

With the above setup, the VIP (the RAMP_IP variable) is automatically re-assigned when the ramp node host that currently has it assigned fails.

Chapter 26. Aggregating Container Logs

Overview

As an OpenShift Container Platform cluster administrator, you can deploy the EFK stack to aggregate logs for a range of OpenShift Container Platform services. Application developers can view the logs of the projects for which they have view access. The EFK stack aggregates logs from hosts and applications, whether coming from multiple containers or even deleted pods.

The EFK stack is a modified version of the ELK stack and is comprised of:

Elasticsearch: An object store where all logs are stored.

Fluentd: Gathers logs from nodes and feeds them to Elasticsearch.

Kibana: A web UI for Elasticsearch.

Once deployed in a cluster, the stack aggregates logs from all nodes and projects into Elasticsearch, and provides a Kibana UI to view any logs. Cluster administrators can view all logs, but application developers can only view logs for projects they have permission to view. The stack components communicate securely.

Note

Managing Docker Container Logs discusses the use of json-file logging driver options to manage container logs and prevent filling node disks.

Pre-deployment Configuration

Ensure that you have deployed a router for the cluster.

Ensure that you have the necessary storage for Elasticsearch. Note that each Elasticsearch replica requires its own storage volume. See Elasticsearch for more information.

Ansible-based installs should create the logging-deployer-template template in the openshift project. Otherwise you can create it with the following command:

$ oc apply -n openshift -f \
    /usr/share/openshift/examples/infrastructure-templates/enterprise/logging-deployer.yaml

Create a new project. Once implemented in a single project, the EFK stack collects logs for every project within your OpenShift Container Platform cluster. The examples in this topic use logging as an example project:

$ oadm new-project logging --node-selector=""
$ oc project logging

Note

Specifying an empty node selector on the project is recommended, as Fluentd should be deployed throughout the cluster and any selector would restrict where it is deployed. To control component placement, specify node selectors per component to be applied to their deployment configurations.

Create the logging service accounts and custom roles:

$ oc new-app logging-deployer-account-template

Note

If you deployed logging previously, for example in a different project, then it is normal for the cluster roles to fail to be created because they already exist.

Enable the deployer service account to create an OAuthClient (normally a cluster administrator privilege) for Kibana to use later when authenticating against the master.

$ oadm policy add-cluster-role-to-user oauth-editor \
       system:serviceaccount:logging:logging-deployer

Use the project you created earlier (for example, logging) when specifying this service account.

Enable the Fluentd service account to mount and read system logs by adding it to the privileged security context, and also enable it to read pod metadata by giving it the cluster-reader role:

$ oadm policy add-scc-to-user privileged  \
    system:serviceaccount:logging:aggregated-logging-fluentd
$ oadm policy add-cluster-role-to-user cluster-reader \
    system:serviceaccount:logging:aggregated-logging-fluentd

Use the project you created earlier (for example, logging) when specifying this service account.

Enable the Elasticsearch service account to get cluster role bindings so that it can verify a user’s roles and allow access to operations logs:

$ oadm policy add-cluster-role-to-user rolebinding-reader \
     system:serviceaccount:logging:aggregated-logging-elasticsearch

Use the project you created earlier (for example, logging) when specifying this service account.

Ensure that port 9300 is open. By default the Elasticsearch service uses port 9300 for TCP communication between nodes in a cluster.

Specifying Deployer Parameters

Parameters for the EFK deployment may be specified in the form of a ConfigMap, a secret, or template parameters (which are passed to the deployer in environment variables). The deployer looks for each value first in a logging-deployer ConfigMap, then a logging-deployer secret, then as an environment variable. Any or all may be omitted if not needed. If you are specifying values within a ConfigMap, the values will not be reflected in the output from oc new-app, but will still precede the corresponding template values within the deployer pod.

The available parameters are outlined below. Typically, you should at least specify the host name at which Kibana should be exposed to client browsers, and also the master URL where client browsers will be directed to for authenticating to OpenShift Container Platform.

Create a ConfigMap to provide most deployer parameters. An invocation supplying the most important parameters might be:

$ oc create configmap logging-deployer \
   --from-literal kibana-hostname=kibana.example.com \
   --from-literal public-master-url=https://master.example.com:8443 \
   --from-literal es-cluster-size=3 \
   --from-literal es-instance-ram=8G

Edit the ConfigMap YAML file after creating it:

$ oc edit configmap logging-deployer

Other parameters are available. Read the ElasticSearch section before choosing ElasticSearch parameters for the deployer, and the Fluentd section for some possible parameters:

Parameter
Description

kibana-hostname

The external host name for web clients to reach Kibana.

public-master-url

The external URL for the master; used for OAuth purposes.

es-cluster-size (default: 1)

The number of instances of Elasticsearch to deploy. Redundancy requires at least three, and more can be used for scaling.

es-instance-ram (default: 8G)

Amount of RAM to reserve per Elasticsearch instance. The default is 8G (for 8GB), and it must be at least 512M. Possible suffixes are G,g,M,m.

es-pvc-prefix (default: logging-es-)

Prefix for the names of persistent volume claims to be used as storage for Elasticsearch instances; a number will be appended per instance (for example, logging-es-1). If they do not already exist, they will be created with size es-pvc-size.

es-pvc-size

Size of the persistent volume claim to create per ElasticSearch instance, 100G, for example. If omitted, no PVCs are created and ephemeral volumes are used instead.

es-pvc-dynamic

Set to true to have created persistent volume claims annotated so that their backing storage can be dynamically provisioned (if that is available for your cluster).

storage-group

Number of a supplemental group ID for access to Elasticsearch storage volumes; backing volumes should allow access by this group ID (defaults to 65534).

fluentd-nodeselector (default: logging-infra-fluentd=true)

A node selector that specifies which nodes are eligible targets for deploying Fluentd instances. All nodes where Fluentd should run (typically, all) must have this label before Fluentd will be able to run and collect logs.

es-nodeselector

A node selector that specifies which nodes are eligible targets for deploying Elasticsearch instances. This can be used to place these instances on nodes reserved and/or optimized for running them. For example, the selector could be node-type=infrastructure. At least one active node must have this label before Elasticsearch will deploy.

kibana-nodeselector

A node selector that specifies which nodes are eligible targets for deploying Kibana instances.

curator-nodeselector

A node selector that specifies which nodes are eligible targets for deploying Curator instances.

enable-ops-cluster

If set to true, configures a second Elasticsearch cluster and Kibana for operations logs. Fluentd splits logs between the main cluster and a cluster reserved for operations logs (which consists of /var/log/messages on nodes and the logs from the projects default, openshift, and openshift-infra). This means a second Elasticsearch and Kibana are deployed. The deployments are distinguishable by the -ops included in their names and have parallel deployment options listed below.

kibana-ops-hostname, es-ops-instance-ram, es-ops-pvc-size, es-ops-pvc-prefix, es-ops-cluster-size, es-ops-nodeselector, kibana-ops-nodeselector, curator-ops-nodeselector

Parallel parameters for the ops log cluster.

image-pull-secret

Specify the name of an existing pull secret to be used for pulling component images from an authenticated registry.

Create a secret to provide security-related files to the deployer. Providing the secret is optional, and the objects will be randomly generated if not supplied.

You can supply the following files when creating a new secret, for example:

$ oc create secret generic logging-deployer \
   --from-file kibana.crt=/path/to/cert \
   --from-file kibana.key=/path/to/key

File Name
Description

kibana.crt

A browser-facing certificate for the Kibana server.

kibana.key

A key to be used with the Kibana certificate.

kibana-ops.crt

A browser-facing certificate for the Ops Kibana server.

kibana-ops.key

A key to be used with the Ops Kibana certificate.

server-tls.json

JSON TLS options to override the Kibana server defaults. Refer to Node.JS docs for available options.

ca.crt

A certificate for a CA that will be used to sign all certificates generated by the deployer.

ca.key

A matching CA key.

Deploying the EFK Stack

The EFK stack is deployed using a template to create a deployer pod that reads the deployment parameters and manages the deployment.

Run the deployer, optionally specifying parameters (described in the table below), for example:

Without template parameters:

$ oc new-app logging-deployer-template

With parameters:

$ oc new-app logging-deployer-template \
             --param IMAGE_VERSION=<tag> \
             --param MODE=install

Replace <tag> with v3.4.1 for the latest version.

Parameter Name
Description

IMAGE_PREFIX

The prefix for logging component images. For example, setting the prefix to registry.access.redhat.com/openshift3/ creates registry.access.redhat.com/openshift3/logging-deployer:latest.

IMAGE_VERSION

The version for logging component images. For example, setting the version to v3.3 creates registry.access.redhat.com/openshift3/logging-deployer:v3.3.

MODE (default: install)

Mode to run the deployer in; one of install, uninstall, reinstall, upgrade, migrate, start, stop.

Running the deployer creates a deployer pod and prints its name. Wait until the pod is running. This can take up to a few minutes for OpenShift Container Platform to retrieve the deployer image from the registry. Watch its process with:

$ oc get pod/<pod_name> -w

It will eventually enter Running status and end in Complete status. If takes too long to start, retrieve more details about the pod and any associated events with:

$ oc describe pod/<pod_name>

Check the logs if the deployment does not complete successfully:

$ oc logs -f <pod_name>

Once deployment completes successfully, you may need to label the nodes for Fluentd to deploy on, and may have other adjustments to make to the deployed components. These tasks are described in the next section.

Understanding and Adjusting the Deployment

This section describes adjustments that you can make to deployed components.

Ops Cluster

Note

The logs for the default, openshift, and openshift-infra projects are automatically aggregated and grouped into the .operations item in the Kibana interface.

The project where you have deployed the EFK stack (logging, as documented here) is not aggregated into .operations and is found under its ID.

If you set enable-ops-cluster to true for the deployer, Fluentd is configured to split logs between the main ElasticSearch cluster and another cluster reserved for operations logs (which are defined as node system logs and the projects default, openshift, and openshift-infra). Therefore, a separate Elasticsearch cluster, a separate Kibana, and a separate Curator are deployed to index, access, and manage operations logs. These deployments are set apart with names that include -ops. Keep these separate deployments in mind if you enabled this option. Most of the following discussion also applies to the operations cluster if present, just with the names changed to include -ops.

Elasticsearch

A highly-available environment requires at least three replicas of Elasticsearch; each on a different host. Elasticsearch replicas require their own storage, but an OpenShift Container Platform deployment configuration shares storage volumes between all its pods. So, when scaled up, the EFK deployer ensures each replica of Elasticsearch has its own deployment configuration.

It is possible to scale your cluster up after creation by adding more deployments from a template; however, scaling up (or down) requires the correct procedure and an awareness of clustering parameters (to be described in a separate section). It is best to indicate the desired scale at first deployment.

Refer to Elastic’s documentation for considerations involved in choosing storage and network location as directed below.

Viewing all Elasticsearch Deployments

To view all current Elasticsearch deployments:

$ oc get dc --selector logging-infra=elasticsearch

Node Selector

Because Elasticsearch can use a lot of resources, all members of a cluster should have low latency network connections to each other and to any remote storage. Ensure this by directing the instances to dedicated nodes, or a dedicated region within your cluster, using a node selector.

To configure a node selector, specify the es-nodeselector configuration option at deployment. This applies to all Elasticsearch deployments; if you need to individualize the node selectors, you must manually edit each deployment configuration after deployment.

Persistent Elasticsearch Storage

By default, the deployer creates an ephemeral deployment in which all of a pod’s data is lost upon restart. For production usage, specify a persistent storage volume for each Elasticsearch deployment configuration. You can create the necessary persistent volume claims before deploying or have them created for you. The PVCs must be named based on the es-pvc-prefix setting, which defaults to logging-es-; each PVC name will have a sequence number added to it, so logging-es-1, logging-es-2, and so on. If a PVC needed for the deployment exists already, it is used; if not, and es-pvc-size has been specified, it is created with a request for that size.

Warning

Using NFS storage as a volume or a persistent volume (or via NAS such as Gluster) is not supported for Elasticsearch storage, as Lucene relies on file system behavior that NFS does not supply. Data corruption and other problems can occur. If NFS storage is a requirement, you can allocate a large file on a volume to serve as a storage device and mount it locally on one host. For example, if your NFS storage volume is mounted at /nfs/storage:

$ truncate -s 1T /nfs/storage/elasticsearch-1
$ mkfs.xfs /nfs/storage/elasticsearch-1
$ mount -o loop /nfs/storage/elasticsearch-1 /usr/local/es-storage
$ chown 1000:1000 /usr/local/es-storage

Then, use /usr/local/es-storage as a host-mount as described below. Use a different backing file as storage for each Elasticsearch replica.

This loopback must be maintained manually outside of OpenShift Container Platform, on the node. You must not maintain it from inside a container.

It is possible to use a local disk volume (if available) on each node host as storage for an Elasticsearch replica. Doing so requires some preparation as follows.

The relevant service account must be given the privilege to mount and edit a local volume:

$ oadm policy add-scc-to-user privileged  \
       system:serviceaccount:logging:aggregated-logging-elasticsearch

Use the project you created earlier (for example, logging) when specifying this service account.

Each Elasticsearch replica definition must be patched to claim that privilege, for example:

$ for dc in $(oc get deploymentconfig --selector logging-infra=elasticsearch -o name); do
    oc scale $dc --replicas=0
    oc patch $dc \
       -p '{"spec":{"template":{"spec":{"containers":[{"name":"elasticsearch","securityContext":{"privileged": true}}]}}}}'
  done

The Elasticsearch replicas must be located on the correct nodes to use the local storage, and should not move around even if those nodes are taken down for a period of time. This requires giving each Elasticsearch replica a node selector that is unique to a node where an administrator has allocated storage for it. To configure a node selector, edit each Elasticsearch deployment configuration and add or edit the nodeSelector section to specify a unique label that you have applied for each desired node:

apiVersion: v1
kind: DeploymentConfig
spec:
  template:
    spec:
      nodeSelector:
        logging-es-node: "1"

This label should uniquely identify a replica with a single node that bears that label, in this case logging-es-node=1. Use the oc label command to apply labels to nodes as needed.

To automate applying the node selector you can instead use the oc patch command:

$ oc patch dc/logging-es-<suffix> \
   -p '{"spec":{"template":{"spec":{"nodeSelector":{"logging-es-node":"1"}}}}}'

Once these steps are taken, a local host mount can be applied to each replica as in this example (where we assume storage is mounted at the same path on each node):

$ for dc in $(oc get deploymentconfig --selector logging-infra=elasticsearch -o name); do
    oc set volume $dc \
          --add --overwrite --name=elasticsearch-storage \
          --type=hostPath --path=/usr/local/es-storage
    oc deploy --latest $dc
    oc scale $dc --replicas=1
  done

Changing the Scale of Elasticsearch

If you need to scale up the number of Elasticsearch instances your cluster uses, it is not as simple as scaling up an Elasticsearch deployment configuration. This is due to the nature of persistent volumes and how Elasticsearch is configured to store its data and recover the cluster. Instead, scaling up requires creating a deployment configuration for each Elasticsearch cluster node.

By far the simplest way to change the scale of Elasticsearch is to reinstall the whole deployment. Assuming you have supplied persistent storage for the deployment, this should not be very disruptive. Simply re-run the deployer with the updated es-cluster-size configuration value and the MODE=reinstall template parameter. For example:

$ oc edit configmap logging-deployer
  [change es-cluster-size value to 5]
$ oc new-app logging-deployer-template --param MODE=reinstall

If you previously deployed using template parameters rather than a ConfigMap, this would be a good time to create a ConfigMap instead for future deployer execution.

If you do not wish to reinstall, for instance because you have made customizations that you would like to preserve, then it is possible to add new Elasticsearch deployment configurations to the cluster using a template supplied by the deployer. This requires a more complicated procedure however.

During installation, the deployer creates templates with the Elasticsearch configurations provided to it: logging-es-template (and logging-es-ops-template if the deployer was run with ENABLE_OPS_CLUSTER=true). You can use these for scaling, but you need to adjust the size-related parameters in the templates:

Parameter
Description

NODE_QUORUM

The quorum required to elect a new master. Should be more than half the intended cluster size.

RECOVER_AFTER_NODES

When restarting the cluster, require this many nodes to be present before starting recovery. Defaults to one less than the cluster size to allow for one missing node.

RECOVER_EXPECTED_NODES

When restarting the cluster, wait for this number of nodes to be present before starting recovery. By default, the same as the cluster size.

The node quorum and recovery settings in the template were set based on the es-[ops-]cluster-size value initially provided to the deployer. Since the cluster size is changing, those values need to be overridden.

The existing deployment configurations for that cluster also need to have the three environment variable values above updated. To edit each of the configurations for the cluster in series, you may use the following command:

$ oc edit $(oc get dc -l component=es[-ops] -o name)

Edit the environment variables supplied so that the next time they restart, they will begin with the correct values. For example, for a cluster of size 5, you would set NODE_QUORUM to 3, RECOVER_AFTER_NODES to 4, and RECOVER_EXPECTED_NODES to 5.

Create additional deployment configurations by running the following command against the Elasticsearch cluster you want to to scale up for (logging-es-template or logging-es-ops-template), overriding the parameters as above.

$ oc new-app logging-es[-ops]-template \
     --param NODE_QUORUM=3 \
     --param RECOVER_AFTER_NODES=4 \
     --param RECOVER_EXPECTED_NODES=5

These deployments will be named differently, but all will have the logging-es prefix.

Each new deployment configuration is created without a persistent volume. If you want to attach a persistent volume to it, after creation you can use the oc set volume command to do so, for example:

$ oc volume dc/logging-es-<suffix> \
          --add --overwrite --name=elasticsearch-storage \
          --type=persistentVolumeClaim --claim-name=<your_pvc>

After the intended number of deployment configurations are created, scale up each new one to deploy it:

$ oc scale --replicas=1 dc/logging-es-<suffix>

Fluentd

Fluentd is deployed as a DaemonSet that deploys replicas according to a node label selector (which you can specify with the deployer parameter fluentd-nodeselector; the default is logging-infra-fluentd).

Once you have ElasticSearch running as desired, label the nodes intended for Fluentd deployment to feed their logs into ES. The example below would label a node named node.example.com using the default Fluentd node selector:

$ oc label node/node.example.com logging-infra-fluentd=true

Alternatively, you can label all nodes with:

$ oc label node --all logging-infra-fluentd=true

Note

Labeling nodes requires cluster administrator capability.

Having Fluentd Use the Systemd Journal as the Log Source

By default, Fluentd reads from /var/log/messages and /var/log/containers/<container>.log for system logs and container logs, respectively. You can instead use the systemd journal as the log source. There are three deployer configuration parameters available in the deployer ConfigMap:

Parameter
Description

use-journal

The default is empty, which tells the deployer to have Fluentd check which log driver Docker is using. If Docker is using --log-driver=journald, Fluentd reads from the systemd journal, otherwise, it assumes docker is using the json-file log driver and reads from the /var/log file sources. You can specify the use-journal option as true or false to be explicit about which log source to use. Using the systemd journal requires docker-1.10 or later, and Docker must be configured to use --log-driver=journald.

journal-source

The default is empty, so that when using the systemd journal, Fluentd first looks for /var/log/journal, and if that is not available, uses /run/log/journal as the journal source. You can specify journal-source with an explicit journal path. For example, if you want Fluentd to always read logs from the transient in-memory journal, set journal-source=/run/log/journal.

journal-read-from-head

If this setting is false, Fluentd starts reading from the end of the journal, ignoring historical logs. If this setting is true, Fluentd starts reading logs from the beginning of the journal.

Note

As of OpenShift Container Platform 3.3, Fluentd no longer reads historical log files when using the JSON file log driver. In situations where clusters have a large number of log files and are older than the EFK deployment, this avoids delays when pushing the most recent logs into Elasticsearch. Curator deleting logs are migrated soon after they are added to Elasticsearch.

Note

It may require several minutes, or hours, depending on the size of your journal, before any new log entries are available in Elasticsearch, when using journal-read-from-head=true.

Having Fluentd Send Logs to Another Elasticsearch

Note

The use of ES_COPY is being deprecated. To configure FluentD to send a copy of its logs to an external aggregator, use Fluentd Secure Forward instead.

You can configure Fluentd to send a copy of each log message to both the Elasticsearch instance included with OpenShift Container Platform aggregated logging, and to an external Elasticsearch instance. For example, if you already have an Elasticsearch instance set up for auditing purposes, or data warehousing, you can send a copy of each log message to that Elasticsearch.

This feature is controlled via environment variables on Fluentd, which can be modified as described below.

If its environment variable ES_COPY is true, Fluentd sends a copy of the logs to another Elasticsearch. The names for the copy variables are just like the current ES_HOST, OPS_HOST, and other variables, except that they add _COPY: ES_COPY_HOST, OPS_COPY_HOST, and so on. There are some additional parameters added:

ES_COPY_SCHEME, OPS_COPY_SCHEME - can use either http or https - defaults to https

ES_COPY_USERNAME, OPS_COPY_USERNAME - user name to use to authenticate to Elasticsearch using username/password auth

ES_COPY_PASSWORD, OPS_COPY_PASSWORD - password to use to authenticate to Elasticsearch using username/password auth

Note

Sending logs directly to an AWS Elasticsearch instance is not supported. Use Fluentd Secure Forward to direct logs to an instance of Fluentd that you control and that is configured with the fluent-plugin-aws-elasticsearch-service plug-in.

To set the parameters:

Edit the template for the Fluentd daemonset:

$ oc edit -n logging template logging-fluentd-template

Add or edit the environment variable ES_COPY to have the value "true" (with the quotes), and add or edit the COPY variables listed above.

Recreate the Fluentd daemonset from the template:

$ oc delete daemonset logging-fluentd
$ oc new-app logging-fluentd-template

Configuring Fluentd to Send Logs to an External Log Aggregator

You can configure Fluentd to send a copy of its logs to an external log aggregator, and not the default Elasticsearch, using the secure-forward plug-in. From there, you can further process log records after the locally hosted Fluentd has processed them.

The deployer provides a secure-forward.conf section in the Fluentd configmap for configuring the external aggregator:

<store>
@type secure_forward
self_hostname pod-${HOSTNAME}
shared_key thisisasharedkey
secure yes
enable_strict_verification yes
ca_cert_path /etc/fluent/keys/your_ca_cert
ca_private_key_path /etc/fluent/keys/your_private_key
ca_private_key_passphrase passphrase
<server>
  host ose1.example.com
  port 24284
</server>
<server>
  host ose2.example.com
  port 24284
  standby
</server>
<server>
  host ose3.example.com
  port 24284
  standby
</server>
</store>

This can be updated using the oc edit command:

$ oc edit configmap/logging-fluentd

Certificates to be used in secure-forward.conf can be added to the existing secret that is mounted on the Fluentd pods. The your_ca_cert and your_private_key values must match what is specified in secure-forward.conf in configmap/logging-fluentd:

$ oc patch secrets/logging-fluentd --type=json \
  --patch "[{'op':'add','path':'/data/your_ca_cert','value':'$(base64 /path/to/your_ca_cert.pem)'}]"
$ oc patch secrets/logging-fluentd --type=json \
  --patch "[{'op':'add','path':'/data/your_private_key','value':'$(base64 /path/to/your_private_key.pem)'}]"

Note

Avoid using secret names such as 'cert', 'key', and 'ca' so that the values do not conflict with the keys generated by the Deployer pod for Fluentd to talk to the OpenShift Container Platform hosted Elasticsearch.

When configuring the external aggregator, it must be able to accept messages securely from Fluentd.

If the external aggregator is another Fluentd process, it must have the fluent-plugin-secure-forward plug-in installed and make use of the input plug-in it provides:

<source>
  @type secure_forward

  self_hostname ${HOSTNAME}
  bind 0.0.0.0
  port 24284

  shared_key thisisasharedkey

  secure yes
  cert_path        /path/for/certificate/cert.pem
  private_key_path /path/for/certificate/key.pem
  private_key_passphrase secret_foo_bar_baz
</source>

Further explanation of how to set up the fluent-plugin-secure-forward plug-in can be found here.

Throttling logs in Fluentd

For projects that are especially verbose, an administrator can throttle down the rate at which the logs are read in by Fluentd before being processed.

Warning

Throttling can contribute to log aggregation falling behind for the configured projects; log entries can be lost if a pod is deleted before Fluentd catches up.

Note

Throttling does not work when using the systemd journal as the log source. The throttling implementation depends on being able to throttle the reading of the individual log files for each project. When reading from the journal, there is only a single log source, no log files, so no file-based throttling is available. There is not a method of restricting the log entries that are read into the Fluentd process.

To tell Fluentd which projects it should be restricting, edit the throttle configuration in its ConfigMap after deployment:

$ oc edit configmap/logging-fluentd

The format of the throttle-config.yaml key is a YAML file that contains project names and the desired rate at which logs are read in on each node. The default is 1000 lines at a time per node. For example:

logging:
  read_lines_limit: 500

test-project:
  read_lines_limit: 10

.operations:
  read_lines_limit: 100

Kibana

To access the Kibana console from the OpenShift Container Platform web console, add the loggingPublicURL parameter in the /etc/origin/master/master-config.yaml file, with the URL of the Kibana console (the kibana-hostname parameter). The value must be an HTTPS URL:

...
assetConfig:
  ...
  loggingPublicURL: "https://kibana.example.com"
...

Setting the loggingPublicURL parameter creates a View Archive button on the OpenShift Container Platform web console under the Browse → Pods → <pod_name> → Logs tab. This links to the Kibana console.

You can scale the Kibana deployment as usual for redundancy:

$ oc scale dc/logging-kibana --replicas=2

You can see the user interface by visiting the site specified at the KIBANA_HOSTNAME variable.

See the Kibana documentation for more information on Kibana.

Curator

Curator allows administrators to configure scheduled Elasticsearch maintenance operations to be performed automatically on a per-project basis. It is scheduled to perform actions daily based on its configuration. Only one Curator pod is recommended per Elasticsearch cluster. Curator is configured via a YAML configuration file with the following structure:

$PROJECT_NAME:
  $ACTION:
    $UNIT: $VALUE

$PROJECT_NAME:
  $ACTION:
    $UNIT: $VALUE
 ...

The available parameters are:

Variable Name
Description

$PROJECT_NAME

The actual name of a project, such as myapp-devel. For OpenShift Container Platform operations logs, use the name .operations as the project name.

$ACTION

The action to take, currently only delete is allowed.

$UNIT

One of days, weeks, or months.

$VALUE

An integer for the number of units.

.defaults

Use .defaults as the $PROJECT_NAME to set the defaults for projects that are not specified.

runhour

(Number) the hour of the day in 24-hour format at which to run the Curator jobs. For use with .defaults.

runminute

(Number) the minute of the hour at which to run the Curator jobs. For use with .defaults.

For example, to configure Curator to:

delete indices in the myapp-dev project older than 1 day

delete indices in the myapp-qe project older than 1 week

delete operations logs older than 8 weeks

delete all other projects indices after they are 30 days old

run the Curator jobs at midnight every day

Use:

myapp-dev:
 delete:
   days: 1

myapp-qe:
  delete:
    weeks: 1

.operations:
  delete:
    weeks: 8

.defaults:
  delete:
    days: 30
  runhour: 0
  runminute: 0

Important

When you use month as the $UNIT for an operation, Curator starts counting at the first day of the current month, not the current day of the current month. For example, if today is April 15, and you want to delete indices that are 2 months older than today (delete: months: 2), Curator does not delete indices that are dated older than February 15; it deletes indices older than February 1. That is, it goes back to the first day of the current month, then goes back two whole months from that date. If you want to be exact with Curator, it is best to use days (for example, delete: days: 30).

Creating the Curator Configuration

The deployer provides a ConfigMap from which Curator reads its configuration. You may edit or replace this ConfigMap to reconfigure Curator. Currently the logging-curator ConfigMap is used to configure both your ops and non-ops Curator instances. Any .operations configurations will be in the same location as your application logs configurations.

To edit the provided ConfigMap to configure your Curator instances:

$ oc edit configmap/logging-curator

To replace the provided ConfigMap instead:

$ create /path/to/mycuratorconfig.yaml
$ oc create configmap logging-curator -o yaml \
  --from-file=config.yaml=/path/to/mycuratorconfig.yaml | \
  oc replace -f -

After you make your changes, redeploy Curator:

$ oc deploy --latest dc/logging-curator
$ oc deploy --latest dc/logging-curator-ops

Cleanup

Remove everything generated during the deployment while leaving other project contents intact:

$ oc new-app logging-deployer-template --param MODE=uninstall

Upgrading

To upgrade the EFK logging stack, see Manual Upgrades.

Troubleshooting Kibana

Using the Kibana console with OpenShift Container Platform can cause problems that are easily solved, but are not accompanied with useful error messages. Check the following troubleshooting sections if you are experiencing any problems when deploying Kibana on OpenShift Container Platform:

Login Loop

The OAuth2 proxy on the Kibana console must share a secret with the master host’s OAuth2 server. If the secret is not identical on both servers, it can cause a login loop where you are continuously redirected back to the Kibana login page.

To fix this issue, delete the current OAuthClient, and create a new one, using the same template as before:

$ oc delete oauthclient/kibana-proxy
$ oc new-app logging-support-template

Cryptic Error When Viewing the Console

When attempting to visit the Kibana console, you may receive a browser error instead:

{"error":"invalid_request","error_description":"The request is missing a required parameter,
 includes an invalid parameter value, includes a parameter more than once, or is otherwise malformed."}

This can be caused by a mismatch between the OAuth2 client and server. The return address for the client must be in a whitelist so the server can securely redirect back after logging in.

Fix this issue by replacing the OAuthClient entry:

$ oc delete oauthclient/kibana-proxy
$ oc new-app logging-support-template

If the problem persists, check that you are accessing Kibana at a URL listed in the OAuth client. This issue can be caused by accessing the URL at a forwarded port, such as 1443 instead of the standard 443 HTTPS port. You can adjust the server whitelist by editing the OAuth client:

$ oc edit oauthclient/kibana-proxy

503 Error When Viewing the Console

If you receive a proxy error when viewing the Kibana console, it could be caused by one of two issues.

First, Kibana may not be recognizing pods. If Elasticsearch is slow in starting up, Kibana may timeout trying to reach it. Check whether the relevant service has any endpoints:

$ oc describe service logging-kibana
Name:                   logging-kibana
[...]
Endpoints:              <none>

If any Kibana pods are live, endpoints will be listed. If they are not, check the state of the Kibana pods and deployment. You may need to scale the deployment down and back up again.

The second possible issue may be caused if the route for accessing the Kibana service is masked. This can happen if you perform a test deployment in one project, then deploy in a different project without completely removing the first deployment. When multiple routes are sent to the same destination, the default router will only route to the first created. Check the problematic route to see if it is defined in multiple places:

$ oc get route  --all-namespaces --selector logging-infra=support

F-5 Load Balancer and X-Forwarded-For Enabled

If you are attempting to use a F-5 load balancer in front of Kibana with X-Forwarded-For enabled, this can cause an issue in which the Elasticsearch Searchguard plug-in is unable to correctly accept connections from Kibana.

Example Kibana Error Message

Kibana: Unknown error while connecting to Elasticsearch

Error: Unknown error while connecting to Elasticsearch
Error: UnknownHostException[No trusted proxies]

To configure Searchguard to ignore the extra header:

Scale down all Fluentd pods.

Scale down Elasticsearch after the Fluentd pods have terminated.

Add searchguard.http.xforwardedfor.header: DUMMY to the Elasticsearch configuration section.

$ oc edit configmap/logging-elasticsearch

This approach requires that Elasticsearch’s configurations are within a ConfigMap.

Scale Elasticsearch back up.

Scale up all Fluentd pods.

Sending Logs to an External Elasticsearch Instance

Fluentd sends logs to the value of the ES_HOST, ES_PORT, OPS_HOST, and OPS_PORT environment variables of the Elasticsearch deployment configuration. The application logs are directed to the ES_HOST destination, and operations logs to OPS_HOST.

Note

Sending logs directly to an AWS Elasticsearch instance is not supported. Use Fluentd Secure Forward to direct logs to an instance of Fluentd that you control and that is configured with the fluent-plugin-aws-elasticsearch-service plug-in.

To direct logs to a specific Elasticsearch instance, edit the deployment configuration and replace the value of the above variables with the desired instance:

$ oc edit dc/<deployment_configuration>

For an external Elasticsearch instance to contain both application and operations logs, you can set ES_HOST and OPS_HOST to the same destination, while ensuring that ES_PORT and OPS_PORT also have the same value.

If your externally hosted Elasticsearch instance does not use TLS, update the _CLIENT_CERT, _CLIENT_KEY, and _CA variables to be empty. If it does use TLS, but not mutual TLS, update the _CLIENT_CERT and _CLIENT_KEY variables to be empty and patch or recreate the logging-fluentd secret with the appropriate _CA value for communicating with your Elasticsearch instance. If it uses Mutual TLS as the provided Elasticsearch instance does, patch or recreate the logging-fluentd secret with your client key, client cert, and CA.

Since Fluentd is deployed by a DaemonSet, update the logging-fluentd-template template, delete your current DaemonSet, and recreate it with oc new-app logging-fluentd-template after seeing all previous Fluentd pods have terminated.

Note

If you are not using the provided Kibana and Elasticsearch images, you will not have the same multi-tenant capabilities and your data will not be restricted by user access to a particular project.

Performing Administrative Elasticsearch Operations

As of the Deployer version 3.2.0, an administrator certificate, key, and CA that can be used to communicate with and perform administrative operations on Elasticsearch are provided within the logging-elasticsearch secret.

Note

To confirm whether or not your EFK installation provides these, run:

$ oc describe secret logging-elasticsearch

If they are not available, refer to Manual Upgrades to ensure you are on the latest version first.

Connect to an Elasticsearch pod that is in the cluster on which you are attempting to perform maintenance.

To find a pod in a cluster use either:

$ oc get pods -l component=es -o name | head -1
$ oc get pods -l component=es-ops -o name | head -1

Connect to a pod:

$ oc rsh <your_Elasticsearch_pod>

Once connected to an Elasticsearch container, you can use the certificates mounted from the secret to communicate with Elasticsearch per its 1.5 Document APIs.

Fluentd sends its logs to Elasticsearch using the index format {project_name}.{project_uuid}.YYYY.MM.DD where YYYY.MM.DD is the date of the log record.

For example, to delete all logs for the logging project with uuid 3b3594fa-2ccd-11e6-acb7-0eb6b35eaee3 from June 15, 2016, we can run:

$ curl --key /etc/elasticsearch/secret/admin-key \
  --cert /etc/elasticsearch/secret/admin-cert \
  --cacert /etc/elasticsearch/secret/admin-ca -XDELETE \
  "https://localhost:9200/logging.3b3594fa-2ccd-11e6-acb7-0eb6b35eaee3.2016.06.15"

Chapter 27. Aggregate Logging Sizing Guidelines

Overview

The Elasticsearch, Fluentd, and Kibana (EFK) stack aggregates logs from nodes and applications running inside your OpenShift Container Platform installation. Once deployed it uses Fluentd to aggregate event logs from all nodes, projects, and pods into Elasticsearch (ES). It also provides a centralized Kibana web UI where users and administrators can create rich visualizations and dashboards with the aggregated data.

Fluentd bulk uploads logs to an index, in JSON format, then Elasticsearch routes your search requests to the appropriate shards.

Installation

The general procedure for installing an aggregate logging stack in OpenShift Container Platform is described in Aggregating Container Logs. There are some important things to keep in mind while going through the installation guide:

In order for the logging pods to spread evenly across your cluster, an empty node selector should be used.

$ oadm new-project logging --node-selector=""

In conjunction with node labeling, which is done later, this controls pod placement across the logging project. You can now create the logging project.

$ oc project logging

If you are installing in a PoC or testing environment, a local openshift-ansible template install is recommended.

$ oc create -f ${OPENSHIFT_ANSIBLE_REPO}/roles/openshift_examples/files/examples/${VERSION}/infrastructure-templates/origin/logging-deployer.yaml

Elasticsearch (ES) should be deployed with a cluster size of at least three for resiliency to node failures. This is specified by passing the ES_CLUSTER_SIZE parameter to the installer.

$ oc new-app logging-deployer-template \
                        --param ES_CLUSTER_SIZE=3 \
                        --param PUBLIC_MASTER_URL=$PUBLIC_MASTER_URL \
                        --param KIBANA_HOSTNAME=$KIBANA_URL

Refer to Deploying the EFK Stack for a full list of parameters.

If you do not have an existing Kibana installation, you can use kibana.example.com as a value to KIBANA_HOSTNAME.

Now, ensure Fluentd pod spreading through labeling.

$ oc label nodes --all logging-infra-fluentd=true

This operation requires the cluster-admin default role.

Installation can take some time depending on whether the images were already retrieved from the registry or not, and on the size of your cluster.

Inside the logging namespace, you can check your deployment with oc get all.

$ oc get all

NAME                          REVISION                 REPLICAS      TRIGGERED BY
logging-curator               1                        1
logging-es-6cvk237t           1                        1
logging-es-e5x4t4ai           1                        1
logging-es-xmwvnorv           1                        1
logging-kibana                1                        1
NAME                          DESIRED                  CURRENT       AGE
logging-curator-1             1                        1             3d
logging-es-6cvk237t-1         1                        1             3d
logging-es-e5x4t4ai-1         1                        1             3d
logging-es-xmwvnorv-1         1                        1             3d
logging-kibana-1              1                        1             3d
NAME                          HOST/PORT                PATH          SERVICE              TERMINATION   LABELS
logging-kibana                kibana.example.com                     logging-kibana       reencrypt     component=support,logging-infra=support,provider=openshift
logging-kibana-ops            kibana-ops.example.com                 logging-kibana-ops   reencrypt     component=support,logging-infra=support,provider=openshift
NAME                          CLUSTER-IP               EXTERNAL-IP   PORT(S)              AGE
logging-es                    172.24.155.177           <none>        9200/TCP             3d
logging-es-cluster            None                     <none>        9300/TCP             3d
logging-es-ops                172.27.197.57            <none>        9200/TCP             3d
logging-es-ops-cluster        None                     <none>        9300/TCP             3d
logging-kibana                172.27.224.55            <none>        443/TCP              3d
logging-kibana-ops            172.25.117.77            <none>        443/TCP              3d
NAME                          READY                    STATUS        RESTARTS             AGE
logging-curator-1-6s7wy       1/1                      Running       0                    3d
logging-deployer-un6ut        0/1                      Completed     0                    3d
logging-es-6cvk237t-1-cnpw3   1/1                      Running       0                    3d
logging-es-e5x4t4ai-1-v933h   1/1                      Running       0                    3d
logging-es-xmwvnorv-1-adr5x   1/1                      Running       0                    3d
logging-fluentd-156xn         1/1                      Running       0                    3d
logging-fluentd-40biz         1/1                      Running       0                    3d
logging-fluentd-7dtom         0/1                      Pending       0                    2d
logging-fluentd-8k847         1/1                      Running       0                    3d

You should end up with a similar setup to the below.

$ oc get pods -o wide

NAME                          READY     STATUS      RESTARTS   AGE       NODE
logging-curator-1-6s7wy       1/1       Running     0          3d        ip-172-31-24-239.us-west-2.compute.internal
logging-deployer-un6ut        0/1       Completed   0          3d        ip-172-31-6-152.us-west-2.compute.internal
logging-es-6cvk237t-1-cnpw3   1/1       Running     0          3d        ip-172-31-24-238.us-west-2.compute.internal
logging-es-e5x4t4ai-1-v933h   1/1       Running     0          3d        ip-172-31-24-235.us-west-2.compute.internal
logging-es-xmwvnorv-1-adr5x   1/1       Running     0          3d        ip-172-31-24-233.us-west-2.compute.internal
logging-fluentd-156xn         1/1       Running     0          3d        ip-172-31-24-241.us-west-2.compute.internal
logging-fluentd-40biz         1/1       Running     0          3d        ip-172-31-24-236.us-west-2.compute.internal
logging-fluentd-7dtom         0/1       Pending     0          2d        ip-172-31-24-243.us-west-2.compute.internal
logging-fluentd-8k847         1/1       Running     0          3d        ip-172-31-24-237.us-west-2.compute.internal
logging-fluentd-9a3qx         1/1       Running     0          3d        ip-172-31-24-231.us-west-2.compute.internal
logging-fluentd-abvgj         1/1       Running     0          3d        ip-172-31-24-228.us-west-2.compute.internal
logging-fluentd-bh74n         1/1       Running     0          3d        ip-172-31-24-238.us-west-2.compute.internal
...
...

Notice how the pods are placed in different cluster nodes.

By default the amount of RAM allocated to each ES instance is 8GB. ES_INSTANCE_RAM is the parameter used in the openshift-ansibletemplate. Keep in mind that half of this value will be passed to the individual elasticsearch pods java processes heap size.

Learn more about installing EFK.

Systemd-journald and rsyslog

Rate-limiting

In Red Hat Enterprise Linux (RHEL) 7 the systemd-journald.socket unit creates /dev/log during the boot process, and then passes input to systemd-journald.service. Every syslog() call goes to the journal.

Rsyslog uses the imjournal module as a default input mode for journal files. Refer to Interaction of rsyslog and journal for detailed information about this topic.

A simple test harness was developed, which uses logger across the cluster nodes to make entries of different sizes at different rates in the system log. During testing simulations under a default Red Hat Enterprise Linux (RHEL) 7 installation with systemd-219-19.el7.x86_64 at certain logging rates (approximately 40 log lines per second), we encountered the default rate limit of rsyslogd. After adjusting these limits, entries stopped being written to journald due to local journal file corruption. This issue is resolved in later versions of systemd.

Scaling up

As you scale up your project, the default logging environment might need some adjustments. After updating to systemd-219-22.el7.x86_64, we added:

$IMUXSockRateLimitInterval 0
$IMJournalRatelimitInterval 0

to /etc/rsyslog.conf and:

# Disable rate limiting
RateLimitInterval=1s
RateLimitBurst=10000
Storage=volatile
Compress=no
MaxRetentionSec=5s

to /etc/systemd/journald.conf.

Now, restart the services.

$ systemctl restart systemd-journald.service
$ systemctl restart rsyslog.service

These settings account for the bursty nature of uploading in bulk.

After removing the rate limit, you may see increased CPU utilization on the system logging daemons as it processes any messages that would have previously been throttled.

Rsyslog is configured (see ratelimit.interval, ratelimit.burst) to rate-limit entries read from the journal at 10,000 messages in 300 seconds. A good rule of thumb is to ensure that the rsyslog rate-limits account for the systemd-journald rate-limits.

Scaling up EFK Logging

If you do not indicate the desired scale at first deployment, the least disruptive way of adjusting your cluster is by re-running the deployer with the updated ES_CLUSTER_SIZE value and using the MODE=reinstall template parameter. Refer to the Performing Administrative Elasticsearch Operations section for more in-depth information.

$ oc edit configmap logging-deployer
  [change es-cluster-size value to 5]

$ oc new-app logging-deployer-template --param MODE=reinstall

Storage Considerations

An Elasticsearch index is a collection of shards and its corresponding replica shards. This is how ES implements high availability internally, therefore there is little need to use hardware based mirroring RAID variants. RAID 0 can still be used to increase overall disk performance.

Every search request needs to hit a copy of every shard in the index. Each ES instance requires its own individual storage, but an OpenShift Container Platform deployment can only provide volumes shared by all of its pods, which again means that Elasticsearch shouldn’t be implemented with a single node.

A persistent volume should be added to each Elasticsearch deployment configuration so that we have one volume per replica shard. On OpenShift Container Platform this is often achieved through Persistent Volume Claims

1 volume per shard

1 volume per replica shard

The PVCs must be named based on the es-pvc-prefix setting. Refer to Persistent Elasticsearch Storage for more details.

Below are capacity planning guidelines for OpenShift Container Platform aggregate logging. Example scenario

Assumptions:

Which application: Apache

Bytes per line: 256

Lines per second load on application: 1

Raw text data → JSON

Baseline (256 characters per minute → 15KB/min)

Logging Infra Pods
Storage Throughput

3 es 1 kibana 1 curator 1 fluentd

6 pods total: 90000 x 86400 = 7,7 GB/day

3 es 1 kibana 1 curator 11 fluentd

16 pods total: 225000 x 86400 = 24,0 GB/day

3 es 1 kibana 1 curator 20 fluentd

25 pods total: 225000 x 86400 = 32,4 GB/day

Calculating total logging throughput and disk space required for your logging environment requires knowledge of your application. For example, if one of your applications on average logs 10 lines-per-second, each 256 bytes-per-line, calculate per-application throughput and disk space as follows:

 (bytes-per-line * (lines-per-second) = 2560 bytes per app per second
 (2560) * (number-of-pods-per-node,100) = 256,000 bytes per second per node
 256k * (number-of-nodes) = total logging throughput per cluster

Fluentd ships any logs from /var/log/messages and /var/lib/docker/containers/ to Elasticsearch. Learn more.

Local SSD drives are recommended in order to achieve the best performance. In Red Hat Enterprise Linux (RHEL) 7, the deadline IO scheduler is the default for all block devices except SATA disks. For SATA disks, the default IO scheduler is cfq.

Sizing storage for ES is greatly dependent on how you optimize your indices. Therefore, consider how much data you need in advance and that you are aggregating application log data.

Chapter 28. Enabling Cluster Metrics

Overview

The kubelet exposes metrics that can be collected and stored in back-ends by Heapster.

As an OpenShift Container Platform administrator, you can view a cluster’s metrics from all containers and components in one user interface. These metrics are also used by horizontal pod autoscalers in order to determine when and how to scale.

This topic describes using Hawkular Metrics as a metrics engine which stores the data persistently in a Cassandra database. When this is configured, CPU, memory and network-based metrics are viewable from the OpenShift Container Platform web console and are available for use by horizontal pod autoscalers.

Heapster retrieves a list of all nodes from the master server, then contacts each node individually through the /stats endpoint. From there, Heapster scrapes the metrics for CPU, memory and network usage, then exports them into Hawkular Metrics.

Browsing individual pods in the web console displays separate sparkline charts for memory and CPU. The time range displayed is selectable, and these charts automatically update every 30 seconds. If there are multiple containers on the pod, then you can select a specific container to display its metrics.

If resource limits are defined for your project, then you can also see a donut chart for each pod. The donut chart displays usage against the resource limit. For example: 145 Available of 200 MiB, with the donut chart showing 55 MiB Used.

Before You Begin

The components for cluster metrics must be deployed to the openshift-infra project. This allows horizontal pod autoscalers to discover the Heapster service and use it to retrieve metrics that can be used for autoscaling.

All of the following commands in this topic must be executed under the openshift-infra project. To switch to the openshift-infra project:

$ oc project openshift-infra

To enable cluster metrics, you must next configure the following:

Service Accounts

Metrics Data Storage

Metrics Deployer

Service Accounts

You must configure service accounts for:

Metrics Deployer

Heapster

Metrics Deployer Service Account

The Metrics Deployer will be discussed in a later step, but you must first set up a service account for it:

Create a metrics-deployer service account:

$ oc create -f - <<API
apiVersion: v1
kind: ServiceAccount
metadata:
  name: metrics-deployer
secrets:
- name: metrics-deployer
API

Before it can deploy components, the metrics-deployer service account must also be granted the edit permission for the openshift-infra project:

$ oadm policy add-role-to-user \
    edit system:serviceaccount:openshift-infra:metrics-deployer

Heapster Service Account

The Heapster component requires access to the master server to list all available nodes and access the /stats endpoint for each node. Before it can do this, the Heapster service account requires the cluster-reader permission:

$ oadm policy add-cluster-role-to-user \
    cluster-reader system:serviceaccount:openshift-infra:heapster

Note

The Heapster service account is created automatically during the Deploying the Metrics Components step.

Metrics Data Storage

You can store the metrics data to either persistent storage or to a temporary pod volume.

Persistent Storage

Running OpenShift Container Platform cluster metrics with persistent storage means that your metrics will be stored to a persistent volume and be able to survive a pod being restarted or recreated. This is ideal if you require your metrics data to be guarded from data loss. For production environments it is highly recommended to configure persistent storage for your metrics pods.

The size of the persisted volume can be specified with the CASSANDRA_PV_SIZEtemplate parameter. By default it is set to 10 GB, which may or may not be sufficient for the size of the cluster you are using. If you require more space, for instance 100 GB, you could specify it with something like this:

$ oc process -f metrics-deployer.yaml -v \
    HAWKULAR_METRICS_HOSTNAME=hawkular-metrics.example.com,CASSANDRA_PV_SIZE=100Gi \
    | oc create -f -

The size requirement of the Cassandra storage is dependent on the number of pods. It is the administrator’s responsibility to ensure that the size requirements are sufficient for their setup and to monitor usage to ensure that the disk does not become full.

If you would like to use dynamically provisioned persistent volumes you must set the DYNAMICALLY_PROVISION_STORAGEtemplate option to true for the Metrics Deployer.

Capacity Planning for Cluster Metrics

After the metrics deployer runs, the output of oc get pods should resemble the following:

 # oc get pods -n openshift-infra
 NAME                                READY             STATUS      RESTARTS          AGE
 hawkular-cassandra-1-l5y4g          1/1               Running     0                 17h
 hawkular-metrics-1t9so              1/1               Running     0                 17h
 heapster-febru                      1/1               Running     0                 17h

OpenShift Container Platform metrics are stored using the Cassandra database, which is deployed with settings of MAX_HEAP_SIZE=512M and NEW_HEAP_SIZE=100M. These values should cover most OpenShift Container Platform metrics installations, but you can modify them in the Cassandra Dockerfile prior to deploying cluster metrics.

By default, metrics data is stored for 7 days. You can configure this with the METRIC_DURATION parameter in the metrics.yaml configuration file. After 7 days, Cassandra begins to purge the oldest metrics data. Metrics data for deleted pods and projects is not automatically purged; it is only removed once the data is 7 days old.

Example 28.1. Data Accumulated by 10 Nodes and 1000 Pods

In a test scenario including 10 nodes and 1000 pods, a 24 hour period accumulated 2.5GB of metrics data. Therefore, the capacity planning formula for metrics data in this scenario is:

(((2.5 × 10⁹) ÷ 1000) ÷ 24) ÷ 10⁶ = ~0.125 MB/hour per pod.

Example 28.2. Data Accumulated by 120 Nodes and 10000 Pods

In a test scenario including 120 nodes and 10000 pods, a 24 hour period accumulated 25GB of metrics data. Therefore, the capacity planning formula for metrics data in this scenario is:

(((11.410 × 10⁹) ÷ 1000) ÷ 24) ÷ 10⁶ = 0.475 MB/hour

1000 pods
10000 pods

Cassandra storage data accumulated over 24 hours (default metrics parameters)

2.5GB

11.4GB

If the default value of 7 days for METRIC_DURATION and 10 seconds for METRIC_RESOLUTION are preserved, then weekly storage requirements for the Cassandra pod would be:

1000 pods
10000 pods

Cassandra storage data accumulated over 7 days (default metrics parameters)

20GB

90GB

In the previous table, an additional 10% was added to the expected storage space as a buffer for unexpected monitored pod usage.

Warning

If the Cassandra persisted volume runs out of sufficient space, then data loss will occur.

For cluster metrics to work with persistent storage, ensure that the persistent volume has the ReadWriteOnce access mode. If this mode is not active, then the persistent volume claim cannot locate the persistent volume, and Cassandra fails to start.

To use persistent storage with the metric components, ensure that a persistent volume of sufficient size is available. The creation of persistent volume claims is handled by the Metrics Deployer.

OpenShift Container Platform metrics also supports dynamically-provisioned persistent volumes. To use this feature with OpenShift Container Platform metrics, it is necessary to add an additional flag to the metrics-deployer: DYNAMICALLY_PROVISION_STORAGE=true. You can use EBS, GCE, and Cinder storage back-ends to dynamically provision persistent volumes.

Non-Persistent Storage

Running OpenShift Container Platform cluster metrics with non-persistent storage means that any stored metrics will be deleted when the pod is deleted. While it is much easier to run cluster metrics with non-persistent data, running with non-persistent data does come with the risk of permanent data loss. However, metrics can still survive a container being restarted.

In order to use non-persistent storage, you must set the USE_PERSISTENT_STORAGEtemplate option to false for the Metrics Deployer.

Note

When using non-persistent storage, metrics data will be written to /var/lib/origin/openshift.local.volumes/pods on the node where the Cassandra pod is running. Ensure /var has enough free space to accommodate metrics storage.

Metrics Deployer

The Metrics Deployer deploys and configures all of the metrics components. You can configure it by passing in information from secrets and by passing parameters to the Metrics Deployer’s template.

Using Secrets

The Metrics Deployer will auto-generate self-signed certificates for use between its components and will generate a re-encrypting route to expose the Hawkular Metrics service. This route is what allows the web console to access the Hawkular Metrics service.

In order for the browser running the web console to trust the connection through this route, it must trust the route’s certificate. This can be accomplished by providing your own certificates signed by a trusted Certificate Authority. The Metric Deployer’s secret allows you to pass your own certificates which it will then use when creating the route.

If you do not wish to provide your own certificates, the router’s default certificate will be used instead.

Providing Your Own Certificates

To provide your own certificate which will be used by the re-encrypting route, you can pass these values as secrets to the Metrics Deployer.

The hawkular-metrics.pem value needs to contain the certificate in its .pem format. You may also need to provide the certificate for the Certificate Authority which signed this pem file via the hawkular-metrics-ca.cert secret.

$ oc secrets new metrics-deployer \
    hawkular-metrics.pem=/home/openshift/metrics/hm.pem \
    hawkular-metrics-ca.cert=/home/openshift/metrics/hm-ca.cert

When these secrets are provided, the deployer uses these values to specify the key, certificate and caCertificate values for the re-encrypting route it generated.

For more information, please see the re-encryption route documentation.

Using the Router’s Default Certificate

If the hawkular-metrics.pem value is not specified, the re-encrypting route will use the router’s default certificate, which may not be trusted by browsers.

A secret named metrics-deployer will still be required in this situation. This can be considered a "dummy" secret since the secret it specifies is not actually used by the component.

To create a "dummy" secret that does not specify a certificate value:

$ oc secrets new metrics-deployer nothing=/dev/null

Deployer Secret Options

The following table contains more advanced configuration options, detailing all the secrets which can be used by the deployer:

Secret Name
Description

hawkular-metrics.pem

The pem file to use for the Hawkular Metrics certificate used for the re-encrypting route. This certificate must contain the host name used by the route (e.g., HAWKULAR_METRICS_HOSTNAME). The default router’s certificate is used for the route if this option is unspecified.

hawkular-metrics-ca.cert

The certificate for the CA used to sign the hawkular-metrics.pem. This is optional if the hawkular-metrics.pem does not contain the CA certificate directly.

heapster.cert

The certificate for Heapster to use. This is auto-generated if unspecified.

heapster.key

The key to use with the Heapster certificate. This is ignored if heapster.cert is not specified

heapster_client_ca.cert

The certificate that generates heapster.cert. This is required if heapster.cert is specified. Otherwise, the main CA for the OpenShift Container Platform installation is used. In order for horizontal pod autoscaling to function properly, this should not be overridden.

heapster_allowed_users

A file containing a comma-separated list of CN to accept from certificates signed with the specified CA. By default, this is set to allow the OpenShift Container Platform service proxy to connect. If you override this, make sure to add system:master-proxy to the list in order to allow horizontal pod autoscaling to function properly.

Modifying the Deployer Template

The OpenShift Container Platform installer uses a template to deploy the metrics components. The default template can be found at the following path:

/usr/share/openshift/examples/infrastructure-templates/enterprise/metrics-deployer.yaml

In case you need to make any changes to this file, copy it to another directory with the file name metrics-deployer.yaml and refer to the new location when using it in the following sections.

Deployer Template Parameters

The deployer template parameter options and their defaults are listed in the default metrics-deployer.yaml file. If required, you can override these values when creating the Metrics Deployer.

Table 28.1. Template Parameters

Parameter
Description

METRIC_DURATION

The number of days metrics should be stored.

CASSANDRA_PV_SIZE

The persistent volume size for each of the Cassandra nodes.

CASSANDRA_NODES

The number of initial Cassandra nodes to deploy.

USE_PERSISTENT_STORAGE

Set to true for persistent storage; set to false to use non-persistent storage.

DYNAMICALLY_PROVISION_STORAGE

Set to true to allow for dynamically provisioned storage.

REDEPLOY

If set to true, the deployer will try to delete all the existing components before trying to redeploy.

HAWKULAR_METRICS_HOSTNAME

External host name where clients can reach Hawkular Metrics. This is the FQDN of the machine running the router pod.

MASTER_URL

Internal URL for the master, for authentication retrieval.

IMAGE_VERSION

Specify version for metrics components. For example, for openshift/origin-metrics-deployer:latest, set version to latest.

IMAGE_PREFIX

Specify prefix for metrics components. For example, for openshift/origin-metrics-deployer:latest, set prefix to openshift/origin-.

MODE

Can be set to:

preflight to perform validation before a deployment.

deploy to perform an initial deployment.

refresh to delete and redeploy all components but to keep persisted data and routes.

redeploy to delete and redeploy everything (losing all data in the process).

validate to re-run validations after a deployment.

IGNORE_PREFLIGHT

Can be set to true to disable the preflight checks. This allows the deployer to continue even if the preflight check has failed.

USER_WRITE_ACCESS

Sets whether user accounts should be able to write metrics. Defaults to false so that only Heapster can write metrics and not individual users. It is recommended to disable user write access; if enabled, any user will be able to write metrics to the system which can affect performance and can cause Cassandra disk usage to unpredictably increase.

The only required parameter is HAWKULAR_METRICS_HOSTNAME. This value is required when creating the deployer, because it specifies the host name for the Hawkular Metrics route. This value should correspond to a fully qualified domain name. You must know the value of HAWKULAR_METRICS_HOSTNAME when configuring the console for metrics access.

If you are using persistent storage with Cassandra, it is the administrator’s responsibility to set a sufficient disk size for the cluster using the CASSANDRA_PV_SIZE parameter. It is also the administrator’s responsibility to monitor disk usage to make sure that it does not become full.

Warning

Data loss will result if the Cassandra persisted volume runs out of sufficient space.

All of the other parameters are optional and allow for greater customization. For instance, if you have a custom install in which the Kubernetes master is not available under https://kubernetes.default.svc:443 you can specify the value to use instead with the MASTER_URL parameter. To deploy a specific version of the metrics components, use the IMAGE_VERSION parameter.

Warning

It is highly recommended to not use latest for the IMAGE_VERSION. The latest version corresponds to the very latest version available and can cause issues if it brings in a newer version not meant to function on the version of OpenShift Container Platform you are currently running.

Deploying the Metric Components

Because deploying and configuring all the metric components is handled by the Metrics Deployer, you can simply deploy everything in one step.

The following examples show you how to deploy metrics with and without persistent storage using the default template parameters. Optionally, you can specify any of the template parameters when calling these commands.

Example 28.3. Deploying with Persistent Storage

The following command sets the Hawkular Metrics route to use hawkular-metrics.example.com and is deployed using persistent storage.

You must have a persistent volume of sufficient size available.

$ oc new-app --as=system:serviceaccount:openshift-infra:metrics-deployer \
    -f metrics-deployer.yaml \
    -p HAWKULAR_METRICS_HOSTNAME=hawkular-metrics.example.com

Example 28.4. Deploying without Persistent Storage

The following command sets the Hawkular Metrics route to use hawkular-metrics.example.com and deploy without persistent storage.

$ oc new-app --as=system:serviceaccount:openshift-infra:metrics-deployer \
    -f metrics-deployer.yaml \
    -p HAWKULAR_METRICS_HOSTNAME=hawkular-metrics.example.com \
    -p USE_PERSISTENT_STORAGE=false

Warning

Because this is being deployed without persistent storage, metric data loss can occur.

Metrics Deployer Validations

The metrics deployer does some validation both before and after deployment. If the pre-flight validation fails, the environment for deployment is considered unsuitable and the deployment is aborted. However, you can add IGNORE_PREFLIGHT=true to the deployer parameters if you believe the validation has erred.

If post-deployment validation fails, the deployer finishes in an Error state, which indicates that you should check the deployer logs for issues that may require addressing. For example, the validation may detect that the external hawkular-metrics route is not actually in use, because the route was already created somewhere else. The validation output at the end of a deployment should explain as clearly as possible any issues it finds and what you can do to address them.

Once you have addressed deployment validation issues, you can re-run just the validation by running the deployer again with the MODE=validate parameter added, for example:

$ oc new-app --as=system:serviceaccount:openshift-infra:metrics-deployer \
    -f metrics-deployer.yaml \
    -p HAWKULAR_METRICS_HOSTNAME=hawkular-metrics.example.com \
    -p MODE=validate

There is also a diagnostic for metrics:

$ oadm diagnostics MetricsApiProxy

Setting the Metrics Public URL

The OpenShift Container Platform web console uses the data coming from the Hawkular Metrics service to display its graphs. The URL for accessing the Hawkular Metrics service must be configured via the metricsPublicURL option in the master configuration file (/etc/origin/master/master-config.yaml). This URL corresponds to the route created with the HAWKULAR_METRICS_HOSTNAME template parameter during the deployment of the metrics components.

Note

You must be able to resolve the HAWKULAR_METRICS_HOSTNAME from the browser accessing the console.

For example, if your HAWKULAR_METRICS_HOSTNAME corresponds to hawkular-metrics.example.com, then you must make the following change in the master-config.yaml file:

  assetConfig:
    ...
    metricsPublicURL: "https://hawkular-metrics.example.com/hawkular/metrics"

Once you have updated and saved the master-config.yaml file, you must restart your OpenShift Container Platform instance.

When your OpenShift Container Platform server is back up and running, metrics will be displayed on the pod overview pages.

Caution

If you are using self-signed certificates, remember that the Hawkular Metrics service is hosted under a different host name and uses different certificates than the console. You may need to explicitly open a browser tab to the value specified in metricsPublicURL and accept that certificate.

To avoid this issue, use certificates which are configured to be acceptable by your browser.

Accessing Hawkular Metrics Directly

To access and manage metrics more directly, use the Hawkular Metrics API.

Note

When accessing Hawkular Metrics via the API, you will only be able to perform reads. Writing metrics has been disabled by default. If you want for individual users to also be able to write metrics, you must set the USER_WRITE_ACCESSdeployer template parameter to true.

However, it is recommended to use the default configuration and only have metrics enter the system via Heapster. If write access is enabled, any user will be able to write metrics to the system, which can affect performance and cause Cassandra disk usage to unpredictably increase.

The Hawkular Metrics documentation covers how to use the API, but there are a few differences when dealing with the version of Hawkular Metrics configured for use on OpenShift Container Platform:

OpenShift Container Platform Projects and Hawkular Tenants

Hawkular Metrics is a multi-tenanted application. It is configured so that a project in OpenShift Container Platform corresponds to a tenant in Hawkular Metrics.

As such, when accessing metrics for a project named MyProject you must set the Hawkular-Tenant header to MyProject.

There is also a special tenant named _system which contains system level metrics. This requires either a cluster-reader or cluster-admin level privileges to access.

Authorization

The Hawkular Metrics service will authenticate the user against OpenShift Container Platform to determine if the user has access to the project it is trying to access.

Hawkular Metrics accepts a bearer token from the client and verifies that token with the OpenShift Container Platform server using a SubjectAccessReview. If the user has proper read privileges for the project, they are allowed to read the metrics for that project. For the _system tenant, the user requesting to read from this tenant must have cluster-reader permission.

When accessing the Hawkular Metrics API, you must pass a bearer token in the Authorization header.

Scaling OpenShift Container Platform Metrics Pods

One set of metrics pods (Cassandra/Hawkular/Heapster) is able to monitor at least 10,000 pods.

Caution

Pay attention to system load on nodes where OpenShift Container Platform metrics pods run. Use that information to determine if it is necessary to scale out a number of OpenShift Container Platform metrics pods and spread the load across multiple OpenShift Container Platform nodes. Scaling OpenShift Container Platform metrics heapster pods is not recommended.

Prerequisites

If persistent storage was used to deploy OpenShift Container Platform metrics, then you must create a persistent volume (PV) for the new Cassandra pod to use before you can scale out the number of OpenShift Container Platform metrics Cassandra pods. However, if Cassandra was deployed with dynamically provisioned PVs, then this step is not necessary.

Scaling the Cassandra Components

The Cassandra nodes use persistent storage, therefore scaling up or down is not possible with replication controllers.

Scaling a Cassandra cluster requires you to use the hawkular-cassandra-node template. By default, the Cassandra cluster is a single-node cluster.

To scale out the number of OpenShift Container Platform metrics hawkular pods to two replicas, run:

# oc scale -n openshift-infra --replicas=2 rc hawkular-metrics

Note

If you add a new node to a Cassandra cluster, the data stored in the cluster rebalances across the cluster. The same thing happens If you remove a node from the Cluster.

Horizontal Pod Autoscaling

OpenShift Container Platform version 3.3 does not provide Horizontal Pod Autoscaling (HPA) support for metrics pods and scaling metrics pods.

Cleanup

You can remove everything deloyed by the metrics deployer by performing the following steps:

$ oc delete all,sa,templates,secrets,pvc --selector="metrics-infra"

To remove the deployer components, perform the following steps:

$ oc delete sa,secret metrics-deployer

Chapter 29. Customizing the Web Console

Overview

Administrators can customize the web console using extensions, which let you run scripts and load custom stylesheets when the web console loads. Extension scripts allow you to override the default behavior of the web console and customize it for your needs.

For example, extension scripts can be used to add your own company’s branding or to add company-specific capabilities. A common use case for this is rebranding or white-labelling for different environments. You can use the same extension code, but provide settings that change the web console. You can change the look and feel of nearly any aspect of the user interface in this way.

Loading Extension Scripts and Stylesheets

To add scripts and stylesheets, edit the master configuration file. The scripts and stylesheet files must exist on the Asset Server and are added with the following options:

assetConfig:
  ...
  extensionScripts:
    - /path/to/script1.js
    - /path/to/script2.js
    - ...
  extensionStylesheets:
    - /path/to/stylesheet1.css
    - /path/to/stylesheet2.css
    - ...

Relative paths are resolved relative to the master configuration file. To pick up configuration changes, restart the server.

Custom scripts and stylesheets are read once at server start time. To make developing extensions easier, you can reload scripts and stylesheets on every request by enabling development mode with the following setting:

assetConfig:
  ...
  extensionDevelopment: true

When set, the web console reloads any changes to existing extension script or stylesheet files when you refresh the page in your browser. You still must restart the server when adding new extension stylesheets or scripts, however. This setting is only recommended for testing changes and not for production.

The examples in the following sections show common ways you can customize the web console.

Note

Additional extension examples are available in the OpenShift Origin repository on GitHub.

Setting Extension Properties

If you have a specific extension, but want to use different text in it for each of the environments, you can define the environment in the master-config.yaml file, and use the same extension script across environments. Pass settings from the master-config.yaml file to be used by the extension using the extensionProperties mechanism:

assetConfig:
  extensionDevelopment: true
  extensionProperties:
    doc_url: https://docs.openshift.com
    key1: value1
    key2: value2
  extensionScripts:

This results in a global variable that can be accessed by the extension, as if the following code was executed:

window.OPENSHIFT_EXTENSION_PROPERTIES = {
  doc_url: "https://docs.openshift.com",
  key1: "value1",
  key2: "value2",
}

Customizing the Logo

The following style changes the logo in the web console header:

#header-logo {
  background-image: url("https://www.example.com/images/logo.png");
  width: 190px;
  height: 20px;
}

Replace the example.com URL with a URL to an actual image, and adjust the width and height. The ideal height is 20px.

Save the style to a file (for example, logo.css) and add it to the master configuration file:

assetConfig:
  ...
  extensionStylesheets:
    - /path/to/logo.css

Changing Links to Documentation

Links to external documentation are shown in various sections of the web console. The following example changes the URL for two given links to the documentation:

window.OPENSHIFT_CONSTANTS.HELP['get_started_cli']      = "https://example.com/doc1.html";
window.OPENSHIFT_CONSTANTS.HELP['basic_cli_operations'] = "https://example.com/doc2.html";

Save this script to a file (for example, help-links.js) and add it to the master configuration file:

assetConfig:
  ...
  extensionScripts:
    - /path/to/help-links.js

Adding or Changing Links to Download the CLI

The About page in the web console provides download links for the command line interface (CLI) tools. These links can be configured by providing both the link text and URL, so that you can choose to point them directly to file packages, or to an external page that points to the actual packages.

For example, to point directly to packages that can be downloaded, where the link text is the package platform:

window.OPENSHIFT_CONSTANTS.CLI = {
  "Linux (32 bits)": "https://<cdn>/openshift-client-tools-linux-32bit.tar.gz",
  "Linux (64 bits)": "https://<cdn>/openshift-client-tools-linux-64bit.tar.gz",
  "Windows":         "https://<cdn>/openshift-client-tools-windows.zip",
  "Mac OS X":        "https://<cdn>/openshift-client-tools-mac.zip"
};

Alternatively, to point to a page that links the actual download packages, with the Latest Release link text:

window.OPENSHIFT_CONSTANTS.CLI = {
  "Latest Release": "https://<cdn>/openshift-client-tools/latest.html"
};

Save this script to a file (for example, cli-links.js) and add it to the master configuration file:

assetConfig:
  ...
  extensionScripts:
    - /path/to/cli-links.js

Customizing the About Page

To provide a custom About page for the web console:

Write an extension that looks like:

angular
  .module('aboutPageExtension', ['openshiftConsole'])
  .config(function($routeProvider) {
    $routeProvider
      .when('/about', {
        templateUrl: 'extensions/about/about.html',
        controller: 'AboutController'
      });
    }
  );

Save the script to a file (for example, about/about.js).

Write a customized template.

Start from the version of about.html from the OpenShift Container Platform release you are using. Within the template, there are two angular scope variables available: version.master.openshift and version.master.kubernetes.

Save the custom template to a file (for example, about/about.html).

Modify the master configuration file:

assetConfig:
  ...
  extensionScripts:
    - about/about.js
  ...
  extensions:
    - name: about
      sourceDirectory: /path/to/about

Configuring Navigation Menus

Top Navigation Dropdown Menus

The top navigation bar of the web console contains the help icon and the user dropdown menus. You can add additional menu items to these using the angular-extension-registry.

The available extension points are:

nav-help-dropdown - the help icon dropdown menu, visible at desktop screen widths

nav-user-dropdown - the user dropdown menu, visible at desktop screen widths

nav-dropdown-mobile - the single menu for top navigation items at mobile screen widths

The following example extends the nav-help-dropdown menu, with a name of <myExtensionModule>:

Note

<myExtensionModule> is a placeholder name. Each dropdown menu extension must be unique enough so that it does not clash with any future angular modules.

angular
  .module('<myExtensionModule>', ['openshiftConsole'])
  .run([
    'extensionRegistry',
    function(extensionRegistry) {
      extensionRegistry
        .add('nav-help-dropdown', function() {
          return [
            {
              type: 'dom',
              node: '<li><a href="http://www.example.com/report" target="_blank">Report a Bug</a></li>'
            }, {
              type: 'dom',
              node: '<li class="divider"></li>'  // If you want a horizontal divider to appear in the menu
            }, {
              type: 'dom',
              node: '<li><a href="http://www.example.com/status" target="_blank">System Status</a></li>'
            }
          ];
        });
    }
  ]);

hawtioPluginLoader.addModule('<myExtensionModule>');

Project Left Navigation

When navigating within a project, a menu appears on the left with primary and secondary navigation. This menu structure is defined as a constant and can be overridden or modified.

Note

Significant customizations to the project navigation may affect the user experience and should be done with careful consideration. You may need to update this customization in future upgrades if you modify existing navigation items.

Create the configuration scripts within a file (for example, navigation.js):

// Append a new primary nav item.  This is a simple direct navigation item
// with no secondary menu.
window.OPENSHIFT_CONSTANTS.PROJECT_NAVIGATION.push({
  label: "Dashboard",           // The text label
  iconClass: "fa fa-dashboard", // The icon you want to appear
  href: "/dashboard"            // Where to go when this nav item is clicked.
                                // Relative URLs are pre-pended with the path
                                // '/project/<project-name>'
});

// Splice a primary nav item to a specific spot in the list.  This primary item has
// a secondary menu.
window.OPENSHIFT_CONSTANTS.PROJECT_NAVIGATION.splice(2, 0, { // Insert at the third spot
  label: "Git",
  iconClass: "fa fa-code",
  secondaryNavSections: [       // Instead of an href, a sub-menu can be defined
    {
      items: [
        {
          label: "Branches",
          href: "/git/branches",
          prefixes: [
            "/git/branches/"     // Defines prefix URL patterns that will cause
                                 // this nav item to show the active state, so
                                 // tertiary or lower pages show the right context
          ]
        }
      ]
    },
    {
      header: "Collaboration",   // Sections within a sub-menu can have an optional header
      items: [
        {
          label: "Pull Requests",
          href: "/git/pull-requests",
          prefixes: [
            "/git/pull-requests/"
          ]
        }
      ]
    }
  ]
});

// Add a primary item to the top of the list.  This primary item is shown conditionally.
window.OPENSHIFT_CONSTANTS.PROJECT_NAVIGATION.unshift({
  label: "Getting Started",
  iconClass: "pficon pficon-screen",
  href: "/getting-started",
  prefixes: [                   // Primary nav items can also specify prefixes to trigger
    "/getting-started/"         // active state
  ],
  isValid: function() {         // Primary or secondary items can define an isValid
    return isNewUser;           // function. If present it will be called to test whether
                                // the item should be shown, it should return a boolean
  }
});

// Modify an existing menu item
var applicationsMenu = _.find(window.OPENSHIFT_CONSTANTS.PROJECT_NAVIGATION, { label: 'Applications' });
applicationsMenu.secondaryNavSections.push({ // Add a new secondary nav section to the Applications menu
  // my secondary nav section
});

Save the file and add it to the master configuration at /etc/origin/master/master-config.yml:

assetConfig:
  ...
  extensionScripts:
    - /path/to/navigation.js

Restart the master host:

# systemctl restart atomic-openshift-master

Enabling Features in Technology Preview

Sometimes features are available in Technology Preview. By default, these features are disabled in the web console and hidden from end users.

Web console features currently in Technology Preview include:

Feature Name
Description
Script Value

Pipelines

Enabling this feature will add the Pipelines navigation item underneath the Builds menu.

pipelines

To enable a Technology Preview feature:

Save this script to a file (for example, tech-preview.js):

window.OPENSHIFT_CONSTANTS.ENABLE_TECH_PREVIEW_FEATURE.<feature_name> = true;

Add it to the master configuration file:

assetConfig:
  ...
  extensionScripts:
    - /path/to/tech-preview.js

Serving Static Files

You can serve other files from the Asset Server as well. For example, you might want to make the CLI executable available for download from the web console or add images to use in a custom stylesheet.

Add the directory with the files you want using the following configuration option:

assetConfig:
  ...
  extensions:
    - name: images
      sourceDirectory: /path/to/my_images

The files under the /path/to/my_images directory will be available under the URL /<context>/extensions/images in the web console.

To reference these files from a stylesheet, you should generally use a relative path. For example:

#header-logo {
  background-image: url("../extensions/images/my-logo.png");
}

Enabling HTML5 Mode

The web console has a special mode for supporting certain static web applications that use the HTML5 history API:

assetConfig:
  ...
  extensions:
    - name: my_extension
      sourceDirectory: /path/to/myExtension
      html5Mode: true

Setting html5Mode to true enables two behaviors:

Any request for a non-existent file under /<context>/extensions/my_extension/ instead serves /path/to/myExtension/index.html rather than a "404 Not Found" page.

The element <base href="/"> will be rewritten in /path/to/myExtension/index.html to use the actual base depending on the asset configuration; only this exact string is rewritten.

This is needed for JavaScript frameworks such as AngularJS that require base to be set in index.html.

Customizing the Login Page

You can also change the login page, and the login provider selection page for the web console. Run the following commands to create templates you can modify:

$ oadm create-login-template > login-template.html
$ oadm create-provider-selection-template > provider-selection-template.html

Edit the file to change the styles or add content, but be careful not to remove any required parameters inside the curly brackets.

To use your custom login page or provider selection page, set the following options in the master configuration file:

oauthConfig:
  ...
  templates:
    login: /path/to/login-template.html
    providerSelection: /path/to/provider-selection-template.html

Relative paths are resolved relative to the master configuration file. You must restart the server after changing this configuration.

When there are multiple login providers configured or when the alwaysShowProviderSelection option in the master-config.yaml file is set to true, each time a user’s token to OpenShift Container Platform expires, the user is presented with this custom page before they can proceed with other tasks.

Example Usage

Custom login pages can be used to create Terms of Service information. They can also be helpful if you use a third-party login provider, like GitHub or Google, to show users a branded page that they trust and expect before being redirected to the authentication provider.

Customizing the OAuth Error Page

When errors occur during authentication, you can change the page shown.

Run the following command to create a template you can modify:

$ oadm create-error-template > error-template.html

Edit the file to change the styles or add content.

You can use the Error and ErrorCode variables in the template. To use your custom error page, set the following option in the master configuration file:

oauthConfig:
  ...
  templates:
    error: /path/to/error-template.html

Relative paths are resolved relative to the master configuration file.

You must restart the server after changing this configuration.

Changing the Logout URL

You can change the location a console user is sent to when logging out of the console by modifying the logoutURL parameter in the /etc/origin/master/master-config.yaml file:

...
assetConfig:
  logoutURL: "http://www.example.com"
...

This can be useful when authenticating with Request Header and OAuth or OpenID identity providers, which require visiting an external URL to destroy single sign-on sessions.

Configuring Web Console Customizations with Ansible

During advanced installations, many modifications to the web console can be configured using the following parameters, which are configurable in the inventory file:

openshift_master_logout_url

openshift_master_extension_scripts

openshift_master_extension_stylesheets

openshift_master_extensions

openshift_master_oauth_template

openshift_master_metrics_public_url

openshift_master_logging_public_url

Example Web Console Customization with Ansible

# Configure logoutURL in the master config for console customization
# See: https://docs.openshift.com/enterprise/latest/install_config/web_console_customization.html#changing-the-logout-url
#openshift_master_logout_url=http://example.com

# Configure extensionScripts in the master config for console customization
# See: https://docs.openshift.com/enterprise/latest/install_config/web_console_customization.html#loading-custom-scripts-and-stylesheets
#openshift_master_extension_scripts=['/path/on/host/to/script1.js','/path/on/host/to/script2.js']

# Configure extensionStylesheets in the master config for console customization
# See: https://docs.openshift.com/enterprise/latest/install_config/web_console_customization.html#loading-custom-scripts-and-stylesheets
#openshift_master_extension_stylesheets=['/path/on/host/to/stylesheet1.css','/path/on/host/to/stylesheet2.css']

# Configure extensions in the master config for console customization
# See: https://docs.openshift.com/enterprise/latest/install_config/web_console_customization.html#serving-static-files
#openshift_master_extensions=[{'name': 'images', 'sourceDirectory': '/path/to/my_images'}]

# Configure extensions in the master config for console customization
# See: https://docs.openshift.com/enterprise/latest/install_config/web_console_customization.html#serving-static-files
#openshift_master_oauth_template=/path/on/host/to/login-template.html

# Configure metricsPublicURL in the master config for cluster metrics. Ansible is also able to configure metrics for you.
# See: https://docs.openshift.com/enterprise/latest/install_config/cluster_metrics.html
#openshift_master_metrics_public_url=https://hawkular-metrics.example.com/hawkular/metrics

# Configure loggingPublicURL in the master config for aggregate logging. Ansible is also able to install logging for you.
# See: https://docs.openshift.com/enterprise/latest/install_config/aggregate_logging.html
#openshift_master_logging_public_url=https://kibana.example.com

Chapter 30. Revision History: Installation and Configuration

Thu Feb 16 2017

Affected Topic
Description of Change

Aggregating Container Logs

Fixed example in the Configuring Fluentd to Send Logs to an External Log Aggregator section.

Aggregating Container Logs

Added a version variable and <tag> to code block example in Deploying the EFK Stack section to display the correct current version to use.

Setting up a Router → Using the Default HAProxy Router

Added the Filtering Routes to Specific Routers section.

Installing a Cluster→ Disconnected Isntallation

Added the cluster image to the Synching Images section.

Setting up the Registry → Deploying a Registry on Existing Clusters

Added additional URL instructions to the Deploying the Registry Console section.

Setting up the Registry → Securing and Exposing the Registry

Added a step for adding the public route host name in the --hostnames flag.

Configuring Persistent Storage → Volume Security

Added details about RunAsAny FSGroup and block device permissions.

Aggregating Container Logs

Fixed the options for creating a configuration file in the Creating New Configuration Files section.

Mon Feb 06 2017

Affected Topic
Description of Change

Setting up a Router → Using the Default HAProxy Router

Arranged the topic to create the Creating a Router section, and added a paragraph on router options on creation.

Persistent Storage Examples → Complete Example Using GlusterFS

Clarified that, if using a service, the endpoints name must match the service name.

Configuring Persistent Storage → Persistent Storage Using GlusterFS

Clarified that, if using a service, the endpoints name must match the service name.

Setting up the Registry → Deploying a Registry on Existing Clusters

Added Important box about shutting down Cockpit to the Non-Production Use section.

Installing a Cluster → Host Preparation

Added steps on using yum-config-manager to the host registration steps.

Setting up the Registry → Deploying a Registry on Existing Clusters

Arranged the Securing the Registry Console section to include information on the certificate.

Installing a Cluster → Advanced Install

Added the Configuring a Registry Location section.

Configuring Nuage SDN

Added the Configuring Nuage SDN file.

Tue Jan 31 2017

Affected Topic
Description of Change

Installing a Cluster → Host Preparation

Added instructions for installing and using the atomic-openshift-excluder and atomic-openshift-docker-excluder scripts during cluster installations and upgrades.

Installing a Cluster → Quick Installation

Installing a Cluster → Advanced Installation

Upgrading a Cluster → Manual In-place Upgrades

Upgrading a Cluster → Automated In-place Upgrades

Mon Jan 30 2017

Affected Topic
Description of Change

Setting up the Registry → Securing and Exposing the Registry

Removed references to the deprecated --api-version flag.

Configuring Custom Certificates

Clarified custom certificate configuration locations in the Configuring Custom Certificates section.

Wed Jan 25 2017

Affected Topic
Description of Change

Working with HTTP Proxies

Added step to Proxying Docker Pull for finding the registry service IP.

Setting up a Router → Using the F5 Router Plug-in

Removed references to the deprecated --credentials option.

Installing a Cluster → Prerequisites

Added information about required ports for Aggregated Logging.

Configuring Global Build Defaults and Overrides

Added notes to explain additional values in the /etc/origin/master/master-config.yaml file in the Manually Setting Global Build Defaults section.

Customizing the Web Console

Added information about setting extension properties.

Wed Jan 18 2017

Affected Topic
Description of Change

Setting up the Registry → Securing and Exposing the Registry

Added note box about mounting secrets to service accounts.

Mon Jan 16 2017

Affected Topic
Description of Change

Configuring Authentication and User Agent

Clarified the difference between /api and /oapi in the User Agent section.

Aggregating Container Logs

Added clarification regarding ConfigMaps and output of oc new-app.

Mon Jan 09 2017

Affected Topic
Description of Change

Working with HTTP Proxies

Added clarifying details about HTTP proxies.

Tue Dec 20 2016

Affected Topic
Description of Change

Working with HTTP Proxies

Removed section on configuring Maven with http proxies.

Installing a Cluster → Host Preparation

Updated the path to the latest epel-release package.

Tue Dec 13 2016

Affected Topic
Description of Change

Configuring Persistent Storage → Persistent Storage Using GCE Persistent Disk

Added a new Multi-zone Configuration section.

Configuring Persistent Storage → Dynamically Provisioning Persistent Volumes

Added clarifying details about multi-zone persistent volume (PV) configuration.

Aggregating Container Logs

Added Configuring Fluentd to Send Logs to an External Log Aggregator section.

Added Note boxes explicitly stating that sending logs directly to an AWS Elasticsearch instance is not supported.

Added F-5 Load Balancer and X-Forwarded-For Enabled to the Troubleshooting Kibana section.

Customizing the Web Console

Added a new Customizing the About Page section.

Mon Dec 05 2016

Affected Topic
Description of Change

Installing a Cluster → Prerequisites

Removed Git access as a prerequisite because it is a requirement for development, but not for installing a cluster.

Aggregating Container Logs

Added a NOTE indicating that, as of OpenShift Container Platform 3.3, Fluentd no longer reads historical log files when using the JSON file log driver.

Installing a Cluster → Host Preparation

Added the matches option to the subscription-manager list --available command.

Installing a Cluster → Disconnected Installation

Added the matches option to the subscription-manager list --available command.

Syncing Groups With LDAP

Removed references to filtering UIDAttribute values in configurations.

Mon Nov 21 2016

Affected Topic
Description of Change

Aggregating Container Logs

Clarified points around NFS storage.

Setting up the Registry → Deploying a Registry on Existing Clusters

Removed inaccurate example showing how to attach an existing NFS volume to the registry.

Setting up the Registry → Extended Registry Configuration

Described the CloudFront middleware extension.

Mon Nov 14 2016

Affected Topic
Description of Change

Aggregating Container Logs

Updated the admin-cert location in an example within the Performing Administrative Elasticsearch Operations section.

Installing a Cluster → Advanced Installation

Added steps to verify the web console.

Advance LDAP Configuration → Setting up SSSD for LDAP Failover

Fixed error in Step 3: Apache Configuration section.

Mon Nov 07 2016

Affected Topic
Description of Change

Upgrading a Cluster → Operating System Updates and Upgrades

New topic on the impacts of operating system updates and upgrades and possible solutions.

Advanced LDAP Configuration → Setting up SSSD for LDAP Failover

Fixed incorrect certificate location in the Phase 3: OpenShift Container Platform Configuration section.

Setting up the Registry → Securing and Exposing the Registry

Added clarification to the Exposing a Non-Secure Registry section.

Tue Nov 01 2016

Affected Topic
Description of Change

Installing → Planning

Updated the Sizing Considerations section for clarity.

Thu Oct 27 2016

OpenShift Container Platform 3.3.1 release.

Affected Topic
Description of Change

Upgrading a Cluster → Performing Automated In-place Cluster Upgrades

Minor updates for clarity, including converting some procedures into numbered steps for easier readability.

Mon Oct 17 2016

Affected Topic
Description of Change

Configuring Pipeline Execution

Clarified Jenkins template names.

Loading the Default Image Streams and Templates

Updated information in the Offerings by Subscription Type section on which images are provided by which subscription s.

Installing a Cluster → Advanced Installation

Added more information to the openshift_master_portal_net parameter description in the Configuring Cluster Variables section.

Tue Oct 11 2016

Affected Topic
Description of Change

Aggregating Container Logs

Fixed error in Deploying the EFK Stack section.

Setting up SSSD for LDAP Failover

Corrected steps in the Certificate Generation section.

Configuring the SDN

Added clarifying details to the Migrating Between SDN Plug-ins section about when to clean up SDN-specific artifacts.

Advanced LDAP Configuration → Setting up SSSD for LDAP Failover

Fixed errors in the Phase 2: Authenticating Proxy Setup section.

Configuring Persistent Storage → Persistent Storage Using Ceph Rados Block Device (RBD)

Updated the persistentVolumeReclaimPolicy setting to retain in the Persistent Volume Object Definition Using Ceph RBD example.

Installing → Advanced Installation

Replaced ansible_sudo with ansible_become.

Tue Oct 04 2016

Affected Topic
Description of Change

Configuring the SDN

Added clarifying details to the Migrating Between SDN Plug-ins section about when to clean up SDN-specific artifacts.

Advanced LDAP Configuration → Setting up SSSD for LDAP Failover

Fixed errors in the Phase 2: Authenticating Proxy Setup section.

Configuring the SDN

Added that oc get netnamespace can be run to check VNIDs.

Setting up the Registry → Known Issues

Added troubleshooting guidance on Image Pruning Failures.

Installing → Prerequisites

Added information about disabling dnsmasq.

Installing → Advanced Installation

Added example for a multi-master install with etcd on the same hosts.

Configuring Persistent Storage → Persistent Storage Using Ceph Rados Block Device (RBD)

Updated the persistentVolumeReclaimPolicy setting to retain in the Persistent Volume Object Definition Using Ceph RBD example.

Persistent Storage Examples → Binding Persistent Volumes by Labels

Updated the persistentVolumeReclaimPolicy setting to retain in the glusterfs-pv.yaml example, since recycle is not supported in this case.

Persistent Storage Examples → Complete Example Using GlusterFS

Updated the GlusterFS persistent storage example to use NGNIX instead of busybox.

Configuring Persistent Storage → Volume Security

Fixed formatting of the oc get project default -o yaml example output within the SCCs, Defaults, and Allowed Ranges section.

Configuring Persistent Storage → Volume Security

Removed no_root_squash from the NFS example, as it is not a recommended option.

Tue Sep 27 2016

OpenShift Container Platform 3.3 initial release.

Affected Topic
Description of Change

Configuring the SDN

Added that oc get netnamespace can be run to check VNIDs.

Setting up the Registry → Securing and Exposing the Registry

Added two new sections on Exposing a Secure Registry and Exposing a Non-Secure Registry.

Customizing the Web Console

Added Configuring Navigation Menus section.

Setting up the Registry → Known Issues

Added troubleshooting guidance on Image Pruning Failures.

Master and Node Configuration

Added a Audit Configuration section.

Installing → Prerequisites

Added information about disabling dnsmasq.

Redeploying Certificates

New topic reviewing how to back up and redeploy cluster certificates using the ansible-playbook command.

Installing → Advanced Installation

Added example for a multi-master install with etcd on the same hosts.

Enabling Cluster Metrics

Added capacity planning guidance for OpenShift Container Platform metrics.

Installing → Prerequisites

Updated scale recommendations.

Installing → Advanced Installation

Updated the Multiple Masters Using HAProxy Inventory File example with guidance on applying updated node defaults.

Upgrading → Performing Manual Cluster Upgrades

Updated version numbers for image streams across the Updating the Default Image Streams and Templates section.

Persistent Storage Examples → Binding Persistent Volumes by Labels

Updated the persistentVolumeReclaimPolicy setting to retain in the glusterfs-pv.yaml example, since recycle is not supported in this case.

Persistent Storage Examples → Complete Example Using GlusterFS

Updated the GlusterFS persistent storage example to use NGNIX instead of busybox.

Configuring Pipeline Execution

Corrected instructions for enabling Jenkins auto-provision.

Configuring Routing

Changed "Native Container Routing" topic to "Configuring Routing" and added information about Configuring Route Timeouts.

Aggregating Container Logs

Added clarifying details to the Warning box in the Persistent Elasticsearch Storage section regarding the NFS workaround.

Upgrading → Performing Manual Cluster Upgrades

Added a new Update Your Configuration File section.

Setting up the Registry → Extended Registry Configuration

Emphasized the new mandatory middleware configuration entries.

Deploying a Docker Registry

Extended the registry configuration file example within the Deploying Updated Configuration section to include the blobrepositorycachettl option.

Storage Examples → Binding Persistent Volumes by Labels

New topic providing an end-to-end example for binding persistent volume claims (PVCs) to persistent volumes (PVs) by defining labels in the PV and matching selectors in the PVC.

Persistent Storage Examples → Selector-Label Volume Binding

New topic outlining how to bind persistent volumes claims (PVCs) to persistent volumes (PVs) via selector and label attributes.

Upgrading → Blue-Green Deployments

Added new topic.

Enabling Cluster Metrics

Added additional details to the Accessing Hawkular Metrics Directly section.

Installing → Deploying a Router

Added a new Protecting Against DDoS Attacks section.

Configuring Pipeline Execution

New section.

Installing → Prerequisites

Added that the deserialization cache size can be reduced using a setting in master-config.yaml.

Aggregating Container Logs

Added information about configuration from configmaps, Fluentd, and Curator.

Installing → Deploying a Docker Registry

Edited references to oc secrets add.

Configuring Persistent Storage → Volume Security

Fixed formatting of the oc get project default -o yaml example output within the SCCs, Defaults, and Allowed Ranges section.

Configuring Authentication

Updated OAuth grant strategies information.

Installing → Deploying a Docker Registry

Updated mandatory configuration options for the registry’s configuration file.

Configuring the SDN

Updated migration steps for SDN plug-ins.

Performing Manual Cluster Upgrades

Added a Warning box about excluding roles from reconciliation.

Configuring Authentication

Added OpenID and GitLab challenge options.

Enabling Cluster Metrics

Added a new Metrics Deployer Validations section.

Upgrading → Performing Manual Cluster Upgrades

Added recent image quota restrictions.