Networking

OpenShift Container Platform 4.6

Configuring and managing cluster networking

Red Hat OpenShift Documentation Team

Abstract

This document provides instructions for configuring and managing your OpenShift Container Platform cluster network, including DNS, ingress, and the Pod network.

Chapter 1. Understanding networking

Cluster Administrators have several options for exposing applications that run inside a cluster to external traffic and securing network connections:

  • Service types, such as node ports or load balancers
  • API resources, such as Ingress and Route

By default, Kubernetes allocates each pod an internal IP address for applications running within the pod. Pods and their containers can network, but clients outside the cluster do not have networking access. When you expose your application to external traffic, giving each pod its own IP address means that pods can be treated like physical hosts or virtual machines in terms of port allocation, networking, naming, service discovery, load balancing, application configuration, and migration.

Note

Some cloud platforms offer metadata APIs that listen on the 169.254.169.254 IP address, a link-local IP address in the IPv4 169.254.0.0/16 CIDR block.

This CIDR block is not reachable from the pod network. Pods that need access to these IP addresses must be given host network access by setting the spec.hostNetwork field in the pod spec to true.

If you allow a pod host network access, you grant the pod privileged access to the underlying network infrastructure.

1.1. OpenShift Container Platform DNS

If you are running multiple services, such as front-end and back-end services for use with multiple pods, environment variables are created for user names, service IPs, and more so the front-end pods can communicate with the back-end services. If the service is deleted and recreated, a new IP address can be assigned to the service, and requires the front-end pods to be recreated to pick up the updated values for the service IP environment variable. Additionally, the back-end service must be created before any of the front-end pods to ensure that the service IP is generated properly, and that it can be provided to the front-end pods as an environment variable.

For this reason, OpenShift Container Platform has a built-in DNS so that the services can be reached by the service DNS as well as the service IP/port.

1.2. OpenShift Container Platform Ingress Operator

When you create your OpenShift Container Platform cluster, pods and services running on the cluster are each allocated their own IP addresses. The IP addresses are accessible to other pods and services running nearby but are not accessible to outside clients. The Ingress Operator implements the IngressController API and is the component responsible for enabling external access to OpenShift Container Platform cluster services.

The Ingress Operator makes it possible for external clients to access your service by deploying and managing one or more HAProxy-based Ingress Controllers to handle routing. You can use the Ingress Operator to route traffic by specifying OpenShift Container Platform Route and Kubernetes Ingress resources. Configurations within the Ingress Controller, such as the ability to define endpointPublishingStrategy type and internal load balancing, provide ways to publish Ingress Controller endpoints.

1.2.1. Comparing routes and Ingress

The Kubernetes Ingress resource in OpenShift Container Platform implements the Ingress Controller with a shared router service that runs as a pod inside the cluster. The most common way to manage Ingress traffic is with the Ingress Controller. You can scale and replicate this pod like any other regular pod. This router service is based on HAProxy, which is an open source load balancer solution.

The OpenShift Container Platform route provides Ingress traffic to services in the cluster. Routes provide advanced features that might not be supported by standard Kubernetes Ingress Controllers, such as TLS re-encryption, TLS passthrough, and split traffic for blue-green deployments.

Ingress traffic accesses services in the cluster through a route. Routes and Ingress are the main resources for handling Ingress traffic. Ingress provides features similar to a route, such as accepting external requests and delegating them based on the route. However, with Ingress you can only allow certain types of connections: HTTP/2, HTTPS and server name identification (SNI), and TLS with certificate. In OpenShift Container Platform, routes are generated to meet the conditions specified by the Ingress resource.

Chapter 2. Accessing hosts

Learn how to create a bastion host to access OpenShift Container Platform instances and access the control plane nodes (also known as the master nodes) with secure shell (SSH) access.

2.1. Accessing hosts on Amazon Web Services in an installer-provisioned infrastructure cluster

The OpenShift Container Platform installer does not create any public IP addresses for any of the Amazon Elastic Compute Cloud (Amazon EC2) instances that it provisions for your OpenShift Container Platform cluster. In order to be able to SSH to your OpenShift Container Platform hosts, you must follow this procedure.

Procedure

  1. Create a security group that allows SSH access into the virtual private cloud (VPC) created by the openshift-install command.
  2. Create an Amazon EC2 instance on one of the public subnets the installer created.
  3. Associate a public IP address with the Amazon EC2 instance that you created.

    Unlike with the OpenShift Container Platform installation, you should associate the Amazon EC2 instance you created with an SSH keypair. It does not matter what operating system you choose for this instance, as it will simply serve as an SSH bastion to bridge the internet into your OpenShift Container Platform cluster’s VPC. The Amazon Machine Image (AMI) you use does matter. With Red Hat Enterprise Linux CoreOS (RHCOS), for example, you can provide keys via Ignition, like the installer does.

  4. Once you provisioned your Amazon EC2 instance and can SSH into it, you must add the SSH key that you associated with your OpenShift Container Platform installation. This key can be different from the key for the bastion instance, but does not have to be.

    Note

    Direct SSH access is only recommended for disaster recovery. When the Kubernetes API is responsive, run privileged pods instead.

  5. Run oc get nodes, inspect the output, and choose one of the nodes that is a master. The hostname looks similar to ip-10-0-1-163.ec2.internal.
  6. From the bastion SSH host you manually deployed into Amazon EC2, SSH into that control plane host (also known as the master host). Ensure that you use the same SSH key you specified during the installation:

    $ ssh -i <ssh-key-path> core@<master-hostname>

Chapter 3. Networking Operators overview

OpenShift Container Platform supports multiple types of networking Operators. You can manage the cluster networking using these networking Operators.

3.1. Cluster Network Operator

The Cluster Network Operator (CNO) deploys and manages the cluster network components in an OpenShift Container Platform cluster. This includes deployment of the Container Network Interface (CNI) default network provider plug-in selected for the cluster during installation. For more information, see Cluster Network Operator in OpenShift Container Platform.

3.2. DNS Operator

The DNS Operator deploys and manages CoreDNS to provide a name resolution service to pods. This enables DNS-based Kubernetes Service discovery in OpenShift Container Platform. For more information, see DNS Operator in OpenShift Container Platform.

3.3. Ingress Operator

When you create your OpenShift Container Platform cluster, pods and services running on the cluster are each allocated IP addresses. The IP addresses are accessible to other pods and services running nearby but are not accessible to external clients. The Ingress Operator implements the Ingress Controller API and is responsible for enabling external access to OpenShift Container Platform cluster services. For more information, see Ingress Operator in OpenShift Container Platform.

Chapter 4. Cluster Network Operator in OpenShift Container Platform

The Cluster Network Operator (CNO) deploys and manages the cluster network components on an OpenShift Container Platform cluster, including the Container Network Interface (CNI) default network provider plug-in selected for the cluster during installation.

4.1. Cluster Network Operator

The Cluster Network Operator implements the network API from the operator.openshift.io API group. The Operator deploys the OpenShift SDN default Container Network Interface (CNI) network provider plug-in, or the default network provider plug-in that you selected during cluster installation, by using a daemon set.

Procedure

The Cluster Network Operator is deployed during installation as a Kubernetes Deployment.

  1. Run the following command to view the Deployment status:

    $ oc get -n openshift-network-operator deployment/network-operator

    Example output

    NAME               READY   UP-TO-DATE   AVAILABLE   AGE
    network-operator   1/1     1            1           56m

  2. Run the following command to view the state of the Cluster Network Operator:

    $ oc get clusteroperator/network

    Example output

    NAME      VERSION   AVAILABLE   PROGRESSING   DEGRADED   SINCE
    network   4.5.4     True        False         False      50m

    The following fields provide information about the status of the operator: AVAILABLE, PROGRESSING, and DEGRADED. The AVAILABLE field is True when the Cluster Network Operator reports an available status condition.

4.2. Viewing the cluster network configuration

Every new OpenShift Container Platform installation has a network.config object named cluster.

Procedure

  • Use the oc describe command to view the cluster network configuration:

    $ oc describe network.config/cluster

    Example output

    Name:         cluster
    Namespace:
    Labels:       <none>
    Annotations:  <none>
    API Version:  config.openshift.io/v1
    Kind:         Network
    Metadata:
      Self Link:           /apis/config.openshift.io/v1/networks/cluster
    Spec: 1
      Cluster Network:
        Cidr:         10.128.0.0/14
        Host Prefix:  23
      Network Type:   OpenShiftSDN
      Service Network:
        172.30.0.0/16
    Status: 2
      Cluster Network:
        Cidr:               10.128.0.0/14
        Host Prefix:        23
      Cluster Network MTU:  8951
      Network Type:         OpenShiftSDN
      Service Network:
        172.30.0.0/16
    Events:  <none>

    1
    The Spec field displays the configured state of the cluster network.
    2
    The Status field displays the current state of the cluster network configuration.

4.3. Viewing Cluster Network Operator status

You can inspect the status and view the details of the Cluster Network Operator using the oc describe command.

Procedure

  • Run the following command to view the status of the Cluster Network Operator:

    $ oc describe clusteroperators/network

4.4. Viewing Cluster Network Operator logs

You can view Cluster Network Operator logs by using the oc logs command.

Procedure

  • Run the following command to view the logs of the Cluster Network Operator:

    $ oc logs --namespace=openshift-network-operator deployment/network-operator

4.5. Cluster Network Operator configuration

The configuration for the cluster network is specified as part of the Cluster Network Operator (CNO) configuration and stored in a custom resource (CR) object that is named cluster. The CR specifies the fields for the Network API in the operator.openshift.io API group.

The CNO configuration inherits the following fields during cluster installation from the Network API in the Network.config.openshift.io API group and these fields cannot be changed:

clusterNetwork
IP address pools from which pod IP addresses are allocated.
serviceNetwork
IP address pool for services.
defaultNetwork.type
Cluster network provider, such as OpenShift SDN or OVN-Kubernetes.
Note

After cluster installation, you cannot modify the fields listed in the previous section.

You can specify the cluster network provider configuration for your cluster by setting the fields for the defaultNetwork object in the CNO object named cluster.

4.5.1. Cluster Network Operator configuration object

The fields for the Cluster Network Operator (CNO) are described in the following table:

Table 4.1. Cluster Network Operator configuration object

FieldTypeDescription

metadata.name

string

The name of the CNO object. This name is always cluster.

spec.clusterNetwork

array

A list specifying the blocks of IP addresses from which pod IP addresses are allocated and the subnet prefix length assigned to each individual node in the cluster. For example:

spec:
  clusterNetwork:
  - cidr: 10.128.0.0/19
    hostPrefix: 23
  - cidr: 10.128.32.0/19
    hostPrefix: 23

This value is ready-only and inherited from the Network.config.openshift.io object named cluster during cluster installation.

spec.serviceNetwork

array

A block of IP addresses for services. The OpenShift SDN and OVN-Kubernetes Container Network Interface (CNI) network providers support only a single IP address block for the service network. For example:

spec:
  serviceNetwork:
  - 172.30.0.0/14

This value is ready-only and inherited from the Network.config.openshift.io object named cluster during cluster installation.

spec.defaultNetwork

object

Configures the Container Network Interface (CNI) cluster network provider for the cluster network.

spec.kubeProxyConfig

object

The fields for this object specify the kube-proxy configuration. If you are using the OVN-Kubernetes cluster network provider, the kube-proxy configuration has no effect.

defaultNetwork object configuration

The values for the defaultNetwork object are defined in the following table:

Table 4.2. defaultNetwork object

FieldTypeDescription

type

string

Either OpenShiftSDN or OVNKubernetes. The cluster network provider is selected during installation. This value cannot be changed after cluster installation.

Note

OpenShift Container Platform uses the OpenShift SDN Container Network Interface (CNI) cluster network provider by default.

openshiftSDNConfig

object

This object is only valid for the OpenShift SDN cluster network provider.

ovnKubernetesConfig

object

This object is only valid for the OVN-Kubernetes cluster network provider.

Configuration for the OpenShift SDN CNI cluster network provider

The following table describes the configuration fields for the OpenShift SDN Container Network Interface (CNI) cluster network provider.

Table 4.3. openshiftSDNConfig object

FieldTypeDescription

mode

string

The network isolation mode for OpenShift SDN.

mtu

integer

The maximum transmission unit (MTU) for the VXLAN overlay network. This value is normally configured automatically.

vxlanPort

integer

The port to use for all VXLAN packets. The default value is 4789.

Note

You can only change the configuration for your cluster network provider during cluster installation.

Example OpenShift SDN configuration

defaultNetwork:
  type: OpenShiftSDN
  openshiftSDNConfig:
    mode: NetworkPolicy
    mtu: 1450
    vxlanPort: 4789

Configuration for the OVN-Kubernetes CNI cluster network provider

The following table describes the configuration fields for the OVN-Kubernetes CNI cluster network provider.

Table 4.4. ovnKubernetesConfig object

FieldTypeDescription

mtu

integer

The maximum transmission unit (MTU) for the Geneve (Generic Network Virtualization Encapsulation) overlay network. This value is normally configured automatically.

genevePort

integer

The UDP port for the Geneve overlay network.

Note

You can only change the configuration for your cluster network provider during cluster installation.

Example OVN-Kubernetes configuration

defaultNetwork:
  type: OVNKubernetes
  ovnKubernetesConfig:
    mtu: 1400
    genevePort: 6081

kubeProxyConfig object configuration

The values for the kubeProxyConfig object are defined in the following table:

Table 4.5. kubeProxyConfig object

FieldTypeDescription

iptablesSyncPeriod

string

The refresh period for iptables rules. The default value is 30s. Valid suffixes include s, m, and h and are described in the Go time package documentation.

Note

Because of performance improvements introduced in OpenShift Container Platform 4.3 and greater, adjusting the iptablesSyncPeriod parameter is no longer necessary.

proxyArguments.iptables-min-sync-period

array

The minimum duration before refreshing iptables rules. This field ensures that the refresh does not happen too frequently. Valid suffixes include s, m, and h and are described in the Go time package. The default value is:

kubeProxyConfig:
  proxyArguments:
    iptables-min-sync-period:
    - 0s

4.5.2. Cluster Network Operator example configuration

A complete CNO configuration is specified in the following example:

Example Cluster Network Operator object

apiVersion: operator.openshift.io/v1
kind: Network
metadata:
  name: cluster
spec:
  clusterNetwork: 1
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  serviceNetwork: 2
  - 172.30.0.0/16
  defaultNetwork: 3
    type: OpenShiftSDN
    openshiftSDNConfig:
      mode: NetworkPolicy
      mtu: 1450
      vxlanPort: 4789
  kubeProxyConfig:
    iptablesSyncPeriod: 30s
    proxyArguments:
      iptables-min-sync-period:
      - 0s

1 2 3
Configured only during cluster installation.

4.6. Additional resources

Chapter 5. DNS Operator in OpenShift Container Platform

The DNS Operator deploys and manages CoreDNS to provide a name resolution service to pods, enabling DNS-based Kubernetes Service discovery in OpenShift.

5.1. DNS Operator

The DNS Operator implements the dns API from the operator.openshift.io API group. The Operator deploys CoreDNS using a daemon set, creates a service for the daemon set, and configures the kubelet to instruct pods to use the CoreDNS service IP address for name resolution.

Procedure

The DNS Operator is deployed during installation with a Deployment object.

  1. Use the oc get command to view the deployment status:

    $ oc get -n openshift-dns-operator deployment/dns-operator

    Example output

    NAME           READY     UP-TO-DATE   AVAILABLE   AGE
    dns-operator   1/1       1            1           23h

  2. Use the oc get command to view the state of the DNS Operator:

    $ oc get clusteroperator/dns

    Example output

    NAME      VERSION     AVAILABLE   PROGRESSING   DEGRADED   SINCE
    dns       4.1.0-0.11  True        False         False      92m

    AVAILABLE, PROGRESSING and DEGRADED provide information about the status of the Operator. AVAILABLE is True when at least 1 pod from the CoreDNS daemon set reports an Available status condition.

5.2. View the default DNS

Every new OpenShift Container Platform installation has a dns.operator named default.

Procedure

  1. Use the oc describe command to view the default dns:

    $ oc describe dns.operator/default

    Example output

    Name:         default
    Namespace:
    Labels:       <none>
    Annotations:  <none>
    API Version:  operator.openshift.io/v1
    Kind:         DNS
    ...
    Status:
      Cluster Domain:  cluster.local 1
      Cluster IP:      172.30.0.10 2
    ...

    1
    The Cluster Domain field is the base DNS domain used to construct fully qualified pod and service domain names.
    2
    The Cluster IP is the address pods query for name resolution. The IP is defined as the 10th address in the service CIDR range.
  2. To find the service CIDR of your cluster, use the oc get command:

    $ oc get networks.config/cluster -o jsonpath='{$.status.serviceNetwork}'

Example output

[172.30.0.0/16]

5.3. Using DNS forwarding

You can use DNS forwarding to override the forwarding configuration identified in /etc/resolv.conf on a per-zone basis by specifying which name server should be used for a given zone. If the forwarded zone is the Ingress domain managed by OpenShift Container Platform, then the upstream name server must be authorized for the domain.

Procedure

  1. Modify the DNS Operator object named default:

    $ oc edit dns.operator/default

    This allows the Operator to create and update the ConfigMap named dns-default with additional server configuration blocks based on Server. If none of the servers has a zone that matches the query, then name resolution falls back to the name servers that are specified in /etc/resolv.conf.

    Sample DNS

    apiVersion: operator.openshift.io/v1
    kind: DNS
    metadata:
      name: default
    spec:
      servers:
      - name: foo-server 1
        zones: 2
          - example.com
        forwardPlugin:
          upstreams: 3
            - 1.1.1.1
            - 2.2.2.2:5353
      - name: bar-server
        zones:
          - bar.com
          - example.com
        forwardPlugin:
          upstreams:
            - 3.3.3.3
            - 4.4.4.4:5454

    1
    name must comply with the rfc6335 service name syntax.
    2
    zones must conform to the definition of a subdomain in rfc1123. The cluster domain, cluster.local, is an invalid subdomain for zones.
    3
    A maximum of 15 upstreams is allowed per forwardPlugin.
    Note

    If servers is undefined or invalid, the ConfigMap only contains the default server.

  2. View the ConfigMap:

    $ oc get configmap/dns-default -n openshift-dns -o yaml

    Sample DNS ConfigMap based on previous sample DNS

    apiVersion: v1
    data:
      Corefile: |
        example.com:5353 {
            forward . 1.1.1.1 2.2.2.2:5353
        }
        bar.com:5353 example.com:5353 {
            forward . 3.3.3.3 4.4.4.4:5454 1
        }
        .:5353 {
            errors
            health
            kubernetes cluster.local in-addr.arpa ip6.arpa {
                pods insecure
                upstream
                fallthrough in-addr.arpa ip6.arpa
            }
            prometheus :9153
            forward . /etc/resolv.conf {
                policy sequential
            }
            cache 30
            reload
        }
    kind: ConfigMap
    metadata:
      labels:
        dns.operator.openshift.io/owning-dns: default
      name: dns-default
      namespace: openshift-dns

    1
    Changes to the forwardPlugin triggers a rolling update of the CoreDNS daemon set.

Additional resources

5.4. DNS Operator status

You can inspect the status and view the details of the DNS Operator using the oc describe command.

Procedure

View the status of the DNS Operator:

$ oc describe clusteroperators/dns

5.5. DNS Operator logs

You can view DNS Operator logs by using the oc logs command.

Procedure

View the logs of the DNS Operator:

$ oc logs -n openshift-dns-operator deployment/dns-operator -c dns-operator

Chapter 6. Ingress Operator in OpenShift Container Platform

6.1. OpenShift Container Platform Ingress Operator

When you create your OpenShift Container Platform cluster, pods and services running on the cluster are each allocated their own IP addresses. The IP addresses are accessible to other pods and services running nearby but are not accessible to outside clients. The Ingress Operator implements the IngressController API and is the component responsible for enabling external access to OpenShift Container Platform cluster services.

The Ingress Operator makes it possible for external clients to access your service by deploying and managing one or more HAProxy-based Ingress Controllers to handle routing. You can use the Ingress Operator to route traffic by specifying OpenShift Container Platform Route and Kubernetes Ingress resources. Configurations within the Ingress Controller, such as the ability to define endpointPublishingStrategy type and internal load balancing, provide ways to publish Ingress Controller endpoints.

6.2. The Ingress configuration asset

The installation program generates an asset with an Ingress resource in the config.openshift.io API group, cluster-ingress-02-config.yml.

YAML Definition of the Ingress resource

apiVersion: config.openshift.io/v1
kind: Ingress
metadata:
  name: cluster
spec:
  domain: apps.openshiftdemos.com

The installation program stores this asset in the cluster-ingress-02-config.yml file in the manifests/ directory. This Ingress resource defines the cluster-wide configuration for Ingress. This Ingress configuration is used as follows:

  • The Ingress Operator uses the domain from the cluster Ingress configuration as the domain for the default Ingress Controller.
  • The OpenShift API Server Operator uses the domain from the cluster Ingress configuration. This domain is also used when generating a default host for a Route resource that does not specify an explicit host.

6.3. Ingress controller configuration parameters

The ingresscontrollers.operator.openshift.io resource offers the following configuration parameters.

ParameterDescription

domain

domain is a DNS name serviced by the Ingress controller and is used to configure multiple features:

  • For the LoadBalancerService endpoint publishing strategy, domain is used to configure DNS records. See endpointPublishingStrategy.
  • When using a generated default certificate, the certificate is valid for domain and its subdomains. See defaultCertificate.
  • The value is published to individual Route statuses so that users know where to target external DNS records.

The domain value must be unique among all Ingress controllers and cannot be updated.

If empty, the default value is ingress.config.openshift.io/cluster .spec.domain.

replicas

replicas is the desired number of Ingress controller replicas. If not set, the default value is 2.

endpointPublishingStrategy

endpointPublishingStrategy is used to publish the Ingress controller endpoints to other networks, enable load balancer integrations, and provide access to other systems.

If not set, the default value is based on infrastructure.config.openshift.io/cluster .status.platform:

  • AWS: LoadBalancerService (with external scope)
  • Azure: LoadBalancerService (with external scope)
  • GCP: LoadBalancerService (with external scope)
  • Bare metal: NodePortService
  • Other: HostNetwork

The endpointPublishingStrategy value cannot be updated.

defaultCertificate

The defaultCertificate value is a reference to a secret that contains the default certificate that is served by the Ingress controller. When Routes do not specify their own certificate, defaultCertificate is used.

The secret must contain the following keys and data: * tls.crt: certificate file contents * tls.key: key file contents

If not set, a wildcard certificate is automatically generated and used. The certificate is valid for the Ingress controller domain and subdomains, and the generated certificate’s CA is automatically integrated with the cluster’s trust store.

The in-use certificate, whether generated or user-specified, is automatically integrated with OpenShift Container Platform built-in OAuth server.

namespaceSelector

namespaceSelector is used to filter the set of namespaces serviced by the Ingress controller. This is useful for implementing shards.

routeSelector

routeSelector is used to filter the set of Routes serviced by the Ingress controller. This is useful for implementing shards.

nodePlacement

nodePlacement enables explicit control over the scheduling of the Ingress controller.

If not set, the defaults values are used.

Note

The nodePlacement parameter includes two parts, nodeSelector and tolerations. For example:

nodePlacement:
 nodeSelector:
   matchLabels:
     kubernetes.io/os: linux
 tolerations:
 - effect: NoSchedule
   operator: Exists

tlsSecurityProfile

tlsSecurityProfile specifies settings for TLS connections for Ingress controllers.

If not set, the default value is based on the apiservers.config.openshift.io/cluster resource.

When using the Old, Intermediate, and Modern profile types, the effective profile configuration is subject to change between releases. For example, given a specification to use the Intermediate profile deployed on release X.Y.Z, an upgrade to release X.Y.Z+1 may cause a new profile configuration to be applied to the Ingress controller, resulting in a rollout.

The minimum TLS version for Ingress controllers is 1.1, and the maximum TLS version is 1.2.

Important

The HAProxy Ingress controller image does not support TLS 1.3 and because the Modern profile requires TLS 1.3, it is not supported. The Ingress Operator converts the Modern profile to Intermediate.

The Ingress Operator also converts the TLS 1.0 of an Old or Custom profile to 1.1, and TLS 1.3 of a Custom profile to 1.2.

OpenShift Container Platform router enables Red Hat-distributed OpenSSL default set of TLS 1.3 cipher suites, which uses TLS_AES_128_CCM_SHA256, TLS_CHACHA20_POLY1305_SHA256, TLS_AES_256_GCM_SHA384, and TLS_AES_128_GCM_SHA256. Your cluster might accept TLS 1.3 connections and cipher suites, even though TLS 1.3 is unsupported in OpenShift Container Platform 4.6, 4.7, and 4.8.

Note

Ciphers and the minimum TLS version of the configured security profile are reflected in the TLSProfile status.

routeAdmission

routeAdmission defines a policy for handling new route claims, such as allowing or denying claims across namespaces.

namespaceOwnership describes how hostname claims across namespaces should be handled. The default is Strict.

  • Strict: does not allow routes to claim the same hostname across namespaces.
  • InterNamespaceAllowed: allows routes to claim different paths of the same hostname across namespaces.

wildcardPolicy describes how routes with wildcard policies are handled by the Ingress Controller.

  • WildcardsAllowed: Indicates routes with any wildcard policy are admitted by the Ingress Controller.
  • WildcardsDisallowed: Indicates only routes with a wildcard policy of None are admitted by the Ingress Controller. Updating wildcardPolicy from WildcardsAllowed to WildcardsDisallowed causes admitted routes with a wildcard policy of Subdomain to stop working. These routes must be recreated to a wildcard policy of None to be readmitted by the Ingress Controller. WildcardsDisallowed is the default setting.

IngressControllerLogging

logging defines parameters for what is logged where. If this field is empty, operational logs are enabled but access logs are disabled.

  • access describes how client requests are logged. If this field is empty, access logging is disabled.

    • destination describes a destination for log messages.

      • type is the type of destination for logs:

        • Container specifies that logs should go to a sidecar container. The Ingress Operator configures the container, named logs, on the Ingress Controller pod and configures the Ingress Controller to write logs to the container. The expectation is that the administrator configures a custom logging solution that reads logs from this container. Using container logs means that logs may be dropped if the rate of logs exceeds the container runtime capacity or the custom logging solution capacity.
        • Syslog specifies that logs are sent to a Syslog endpoint. The administrator must specify an endpoint that can receive Syslog messages. The expectation is that the administrator has configured a custom Syslog instance.
      • container describes parameters for the Container logging destination type. Currently there are no parameters for container logging, so this field must be empty.
      • syslog describes parameters for the Syslog logging destination type:

        • address is the IP address of the syslog endpoint that receives log messages.
        • port is the UDP port number of the syslog endpoint that receives log messages.
        • facility specifies the syslog facility of log messages. If this field is empty, the facility is local1. Otherwise, it must specify a valid syslog facility: kern, user, mail, daemon, auth, syslog, lpr, news, uucp, cron, auth2, ftp, ntp, audit, alert, cron2, local0, local1, local2, local3. local4, local5, local6, or local7.
    • httpLogFormat specifies the format of the log message for an HTTP request. If this field is empty, log messages use the implementation’s default HTTP log format. For HAProxy’s default HTTP log format, see the HAProxy documentation.

httpHeaders

httpHeaders defines the policy for HTTP headers.

By setting the forwardedHeaderPolicy for the IngressControllerHTTPHeaders, you specify when and how the Ingress controller sets the Forwarded, X-Forwarded-For, X-Forwarded-Host, X-Forwarded-Port, X-Forwarded-Proto, and X-Forwarded-Proto-Version HTTP headers.

By default, the policy is set to Append.

  • Append specifies that the Ingress Controller appends the headers, preserving any existing headers.
  • Replace specifies that the Ingress Controller sets the headers, removing any existing headers.
  • IfNone specifies that the Ingress Controller sets the headers if they are not already set.
  • Never specifies that the Ingress Controller never sets the headers, preserving any existing headers.
Note

All parameters are optional.

6.3.1. Ingress Controller TLS security profiles

TLS security profiles provide a way for servers to regulate which ciphers a connecting client can use when connecting to the server.

6.3.1.1. Understanding TLS security profiles

You can use a TLS (Transport Layer Security) security profile to define which TLS ciphers are required by various OpenShift Container Platform components. The OpenShift Container Platform TLS security profiles are based on Mozilla recommended configurations.

You can specify one of the following TLS security profiles for each component:

Table 6.1. TLS security profiles

ProfileDescription

Old

This profile is intended for use with legacy clients or libraries. The profile is based on the Old backward compatibility recommended configuration.

The Old profile requires a minimum TLS version of 1.0.

Note

For the Ingress Controller, the minimum TLS version is converted from 1.0 to 1.1.

Intermediate

This profile is the recommended configuration for the majority of clients. It is the default TLS security profile for the Ingress Controller and control plane. The profile is based on the Intermediate compatibility recommended configuration.

The Intermediate profile requires a minimum TLS version of 1.2.

Modern

This profile is intended for use with modern clients that have no need for backwards compatibility. This profile is based on the Modern compatibility recommended configuration.

The Modern profile requires a minimum TLS version of 1.3.

Note

In OpenShift Container Platform 4.6, 4.7, and 4.8, the Modern profile is unsupported. If selected, the Intermediate profile is enabled.

Important

The Modern profile is currently not supported.

Custom

This profile allows you to define the TLS version and ciphers to use.

Warning

Use caution when using a Custom profile, because invalid configurations can cause problems.

Note

OpenShift Container Platform router enables Red Hat-distributed OpenSSL default set of TLS 1.3 cipher suites. Your cluster might accept TLS 1.3 connections and cipher suites, even though TLS 1.3 is unsupported in OpenShift Container Platform 4.6, 4.7, and 4.8.

Note

When using one of the predefined profile types, the effective profile configuration is subject to change between releases. For example, given a specification to use the Intermediate profile deployed on release X.Y.Z, an upgrade to release X.Y.Z+1 might cause a new profile configuration to be applied, resulting in a rollout.

6.3.1.2. Configuring the TLS security profile for the Ingress Controller

To configure a TLS security profile for an Ingress Controller, edit the IngressController custom resource (CR) to specify a predefined or custom TLS security profile. If a TLS security profile is not configured, the default value is based on the TLS security profile set for the API server.

Sample IngressController CR that configures the Old TLS security profile

apiVersion: operator.openshift.io/v1
kind: IngressController
 ...
spec:
  tlsSecurityProfile:
    old: {}
    type: Old
 ...

The TLS security profile defines the minimum TLS version and the TLS ciphers for TLS connections for Ingress Controllers.

You can see the ciphers and the minimum TLS version of the configured TLS security profile in the IngressController custom resource (CR) under Status.Tls Profile and the configured TLS security profile under Spec.Tls Security Profile. For the Custom TLS security profile, the specific ciphers and minimum TLS version are listed under both parameters.

Important

The HAProxy Ingress Controller image does not support TLS 1.3 and because the Modern profile requires TLS 1.3, it is not supported. The Ingress Operator converts the Modern profile to Intermediate. The Ingress Operator also converts the TLS 1.0 of an Old or Custom profile to 1.1, and TLS 1.3 of a Custom profile to 1.2.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.

Procedure

  1. Edit the IngressController CR in the openshift-ingress-operator project to configure the TLS security profile:

    $ oc edit IngressController default -n openshift-ingress-operator
  2. Add the spec.tlsSecurityProfile field:

    Sample IngressController CR for a Custom profile

    apiVersion: operator.openshift.io/v1
    kind: IngressController
     ...
    spec:
      tlsSecurityProfile:
        type: Custom 1
        custom: 2
          ciphers: 3
          - ECDHE-ECDSA-CHACHA20-POLY1305
          - ECDHE-RSA-CHACHA20-POLY1305
          - ECDHE-RSA-AES128-GCM-SHA256
          - ECDHE-ECDSA-AES128-GCM-SHA256
          minTLSVersion: VersionTLS11
     ...

    1
    Specify the TLS security profile type (Old, Intermediate, or Custom). The default is Intermediate.
    2
    Specify the appropriate field for the selected type:
    • old: {}
    • intermediate: {}
    • custom:
    3
    For the custom type, specify a list of TLS ciphers and minimum accepted TLS version.
  3. Save the file to apply the changes.

Verification

  • Verify that the profile is set in the IngressController CR:

    $ oc describe IngressController default -n openshift-ingress-operator

    Example output

    Name:         default
    Namespace:    openshift-ingress-operator
    Labels:       <none>
    Annotations:  <none>
    API Version:  operator.openshift.io/v1
    Kind:         IngressController
     ...
    Spec:
     ...
      Tls Security Profile:
        Custom:
          Ciphers:
            ECDHE-ECDSA-CHACHA20-POLY1305
            ECDHE-RSA-CHACHA20-POLY1305
            ECDHE-RSA-AES128-GCM-SHA256
            ECDHE-ECDSA-AES128-GCM-SHA256
          Min TLS Version:  VersionTLS11
        Type:               Custom
     ...

6.3.2. Ingress controller endpoint publishing strategy

NodePortService endpoint publishing strategy

The NodePortService endpoint publishing strategy publishes the Ingress Controller using a Kubernetes NodePort service.

In this configuration, the Ingress Controller deployment uses container networking. A NodePortService is created to publish the deployment. The specific node ports are dynamically allocated by OpenShift Container Platform; however, to support static port allocations, your changes to the node port field of the managed NodePortService are preserved.

Figure 6.1. Diagram of NodePortService

OpenShift Container Platform Ingress NodePort endpoint publishing strategy

The preceding graphic shows the following concepts pertaining to OpenShift Container Platform Ingress NodePort endpoint publishing strategy:

  • All the available nodes in the cluster have their own, externally accessible IP addresses. The service running in the cluster is bound to the unique NodePort for all the nodes.
  • When the client connects to a node that is down, for example, by connecting the 10.0.128.4 IP address in the graphic, the node port directly connects the client to an available node that is running the service. In this scenario, no load balancing is required. As the image shows, the 10.0.128.4 address is down and another IP address must be used instead.
Note

The Ingress Operator ignores any updates to .spec.ports[].nodePort fields of the service.

By default, ports are allocated automatically and you can access the port allocations for integrations. However, sometimes static port allocations are necessary to integrate with existing infrastructure which may not be easily reconfigured in response to dynamic ports. To achieve integrations with static node ports, you can update the managed service resource directly.

For more information, see the Kubernetes Services documentation on NodePort.

HostNetwork endpoint publishing strategy

The HostNetwork endpoint publishing strategy publishes the Ingress Controller on node ports where the Ingress Controller is deployed.

An Ingress controller with the HostNetwork endpoint publishing strategy can have only one pod replica per node. If you want n replicas, you must use at least n nodes where those replicas can be scheduled. Because each pod replica requests ports 80 and 443 on the node host where it is scheduled, a replica cannot be scheduled to a node if another pod on the same node is using those ports.

6.4. View the default Ingress Controller

The Ingress Operator is a core feature of OpenShift Container Platform and is enabled out of the box.

Every new OpenShift Container Platform installation has an ingresscontroller named default. It can be supplemented with additional Ingress Controllers. If the default ingresscontroller is deleted, the Ingress Operator will automatically recreate it within a minute.

Procedure

  • View the default Ingress Controller:

    $ oc describe --namespace=openshift-ingress-operator ingresscontroller/default

6.5. View Ingress Operator status

You can view and inspect the status of your Ingress Operator.

Procedure

  • View your Ingress Operator status:

    $ oc describe clusteroperators/ingress

6.6. View Ingress Controller logs

You can view your Ingress Controller logs.

Procedure

  • View your Ingress Controller logs:

    $ oc logs --namespace=openshift-ingress-operator deployments/ingress-operator

6.7. View Ingress Controller status

Your can view the status of a particular Ingress Controller.

Procedure

  • View the status of an Ingress Controller:

    $ oc describe --namespace=openshift-ingress-operator ingresscontroller/<name>

6.8. Configuring the Ingress Controller

6.8.1. Setting a custom default certificate

As an administrator, you can configure an Ingress Controller to use a custom certificate by creating a Secret resource and editing the IngressController custom resource (CR).

Prerequisites

  • You must have a certificate/key pair in PEM-encoded files, where the certificate is signed by a trusted certificate authority or by a private trusted certificate authority that you configured in a custom PKI.
  • Your certificate meets the following requirements:

    • The certificate is valid for the ingress domain.
    • The certificate uses the subjectAltName extension to specify a wildcard domain, such as *.apps.ocp4.example.com.
  • You must have an IngressController CR. You may use the default one:

    $ oc --namespace openshift-ingress-operator get ingresscontrollers

    Example output

    NAME      AGE
    default   10m

Note

If you have intermediate certificates, they must be included in the tls.crt file of the secret containing a custom default certificate. Order matters when specifying a certificate; list your intermediate certificate(s) after any server certificate(s).

Procedure

The following assumes that the custom certificate and key pair are in the tls.crt and tls.key files in the current working directory. Substitute the actual path names for tls.crt and tls.key. You also may substitute another name for custom-certs-default when creating the Secret resource and referencing it in the IngressController CR.

Note

This action will cause the Ingress Controller to be redeployed, using a rolling deployment strategy.

  1. Create a Secret resource containing the custom certificate in the openshift-ingress namespace using the tls.crt and tls.key files.

    $ oc --namespace openshift-ingress create secret tls custom-certs-default --cert=tls.crt --key=tls.key
  2. Update the IngressController CR to reference the new certificate secret:

    $ oc patch --type=merge --namespace openshift-ingress-operator ingresscontrollers/default \
      --patch '{"spec":{"defaultCertificate":{"name":"custom-certs-default"}}}'
  3. Verify the update was effective:

    $ echo Q |\
      openssl s_client -connect console-openshift-console.apps.<domain>:443 -showcerts 2>/dev/null |\
      openssl x509 -noout -subject -issuer -enddate

    where:

    <domain>
    Specifies the base domain name for your cluster.

    Example output

    subject=C = US, ST = NC, L = Raleigh, O = RH, OU = OCP4, CN = *.apps.example.com
    issuer=C = US, ST = NC, L = Raleigh, O = RH, OU = OCP4, CN = example.com
    notAfter=May 10 08:32:45 2022 GM

    The certificate secret name should match the value used to update the CR.

Once the IngressController CR has been modified, the Ingress Operator updates the Ingress Controller’s deployment to use the custom certificate.

6.8.2. Removing a custom default certificate

As an administrator, you can remove a custom certificate that you configured an Ingress Controller to use.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You previously configured a custom default certificate for the Ingress Controller.

Procedure

  • To remove the custom certificate and restore the certificate that ships with OpenShift Container Platform, enter the following command:

    $ oc patch -n openshift-ingress-operator ingresscontrollers/default \
      --type json -p $'- op: remove\n  path: /spec/defaultCertificate'

    There can be a delay while the cluster reconciles the new certificate configuration.

Verification

  • To confirm that the original cluster certificate is restored, enter the following command:

    $ echo Q | \
      openssl s_client -connect console-openshift-console.apps.<domain>:443 -showcerts 2>/dev/null | \
      openssl x509 -noout -subject -issuer -enddate

    where:

    <domain>
    Specifies the base domain name for your cluster.

    Example output

    subject=CN = *.apps.<domain>
    issuer=CN = ingress-operator@1620633373
    notAfter=May 10 10:44:36 2023 GMT

6.8.3. Scaling an Ingress Controller

Manually scale an Ingress Controller to meeting routing performance or availability requirements such as the requirement to increase throughput. oc commands are used to scale the IngressController resource. The following procedure provides an example for scaling up the default IngressController.

Procedure

  1. View the current number of available replicas for the default IngressController:

    $ oc get -n openshift-ingress-operator ingresscontrollers/default -o jsonpath='{$.status.availableReplicas}'

    Example output

    2

  2. Scale the default IngressController to the desired number of replicas using the oc patch command. The following example scales the default IngressController to 3 replicas:

    $ oc patch -n openshift-ingress-operator ingresscontroller/default --patch '{"spec":{"replicas": 3}}' --type=merge

    Example output

    ingresscontroller.operator.openshift.io/default patched

  3. Verify that the default IngressController scaled to the number of replicas that you specified:

    $ oc get -n openshift-ingress-operator ingresscontrollers/default -o jsonpath='{$.status.availableReplicas}'

    Example output

    3

Note

Scaling is not an immediate action, as it takes time to create the desired number of replicas.

6.8.4. Configuring Ingress access logging

You can configure the Ingress Controller to enable access logs. If you have clusters that do not receive much traffic, then you can log to a sidecar. If you have high traffic clusters, to avoid exceeding the capacity of the logging stack or to integrate with a logging infrastructure outside of OpenShift Container Platform, you can forward logs to a custom syslog endpoint. You can also specify the format for access logs.

Container logging is useful to enable access logs on low-traffic clusters when there is no existing Syslog logging infrastructure, or for short-term use while diagnosing problems with the Ingress Controller.

Syslog is needed for high-traffic clusters where access logs could exceed the cluster logging stack’s capacity, or for environments where any logging solution needs to integrate with an existing Syslog logging infrastructure. The Syslog use-cases can overlap.

Prerequisites

  • Log in as a user with cluster-admin privileges.

Procedure

Configure Ingress access logging to a sidecar.

  • To configure Ingress access logging, you must specify a destination using spec.logging.access.destination. To specify logging to a sidecar container, you must specify Container spec.logging.access.destination.type. The following example is an Ingress Controller definition that logs to a Container destination:

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      name: default
      namespace: openshift-ingress-operator
    spec:
      replicas: 2
      endpointPublishingStrategy:
        type: NodePortService 1
      logging:
        access:
          destination:
            type: Container
    1
    NodePortService is not required to configure Ingress access logging to a sidecar. Ingress logging is compatible with any endpointPublishingStrategy.
  • When you configure the Ingress Controller to log to a sidecar, the operator creates a container named logs inside the Ingress Controller Pod:

    $ oc -n openshift-ingress logs deployment.apps/router-default -c logs

    Example output

    2020-05-11T19:11:50.135710+00:00 router-default-57dfc6cd95-bpmk6 router-default-57dfc6cd95-bpmk6 haproxy[108]: 174.19.21.82:39654 [11/May/2020:19:11:50.133] public be_http:hello-openshift:hello-openshift/pod:hello-openshift:hello-openshift:10.128.2.12:8080 0/0/1/0/1 200 142 - - --NI 1/1/0/0/0 0/0 "GET / HTTP/1.1"

Configure Ingress access logging to a Syslog endpoint.

  • To configure Ingress access logging, you must specify a destination using spec.logging.access.destination. To specify logging to a Syslog endpoint destination, you must specify Syslog for spec.logging.access.destination.type. If the destination type is Syslog, you must also specify a destination endpoint using spec.logging.access.destination.syslog.endpoint and you can specify a facility using spec.logging.access.destination.syslog.facility. The following example is an Ingress Controller definition that logs to a Syslog destination:

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      name: default
      namespace: openshift-ingress-operator
    spec:
      replicas: 2
      endpointPublishingStrategy:
        type: NodePortService
      logging:
        access:
          destination:
            type: Syslog
            syslog:
              address: 1.2.3.4
              port: 10514
    Note

    The syslog destination port must be UDP.

Configure Ingress access logging with a specific log format.

  • You can specify spec.logging.access.httpLogFormat to customize the log format. The following example is an Ingress Controller definition that logs to a syslog endpoint with IP address 1.2.3.4 and port 10514:

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      name: default
      namespace: openshift-ingress-operator
    spec:
      replicas: 2
      endpointPublishingStrategy:
        type: NodePortService
      logging:
        access:
          destination:
            type: Syslog
            syslog:
              address: 1.2.3.4
              port: 10514
          httpLogFormat: '%ci:%cp [%t] %ft %b/%s %B %bq %HM %HU %HV'

Disable Ingress access logging.

  • To disable Ingress access logging, leave spec.logging or spec.logging.access empty:

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      name: default
      namespace: openshift-ingress-operator
    spec:
      replicas: 2
      endpointPublishingStrategy:
        type: NodePortService
      logging:
        access: null

6.8.5. Ingress Controller sharding

As the primary mechanism for traffic to enter the cluster, the demands on the Ingress Controller, or router, can be significant. As a cluster administrator, you can shard the routes to:

  • Balance Ingress Controllers, or routers, with several routes to speed up responses to changes.
  • Allocate certain routes to have different reliability guarantees than other routes.
  • Allow certain Ingress Controllers to have different policies defined.
  • Allow only specific routes to use additional features.
  • Expose different routes on different addresses so that internal and external users can see different routes, for example.

Ingress Controller can use either route labels or namespace labels as a sharding method.

6.8.5.1. Configuring Ingress Controller sharding by using route labels

Ingress Controller sharding by using route labels means that the Ingress Controller serves any route in any namespace that is selected by the route selector.

Ingress Controller sharding is useful when balancing incoming traffic load among a set of Ingress Controllers and when isolating traffic to a specific Ingress Controller. For example, company A goes to one Ingress Controller and company B to another.

Procedure

  1. Edit the router-internal.yaml file:

    # cat router-internal.yaml
    apiVersion: v1
    items:
    - apiVersion: operator.openshift.io/v1
      kind: IngressController
      metadata:
        name: sharded
        namespace: openshift-ingress-operator
      spec:
        domain: <apps-sharded.basedomain.example.net>
        nodePlacement:
          nodeSelector:
            matchLabels:
              node-role.kubernetes.io/worker: ""
        routeSelector:
          matchLabels:
            type: sharded
      status: {}
    kind: List
    metadata:
      resourceVersion: ""
      selfLink: ""
  2. Apply the Ingress Controller router-internal.yaml file:

    # oc apply -f router-internal.yaml

    The Ingress Controller selects routes in any namespace that have the label type: sharded.

6.8.5.2. Configuring Ingress Controller sharding by using namespace labels

Ingress Controller sharding by using namespace labels means that the Ingress Controller serves any route in any namespace that is selected by the namespace selector.

Ingress Controller sharding is useful when balancing incoming traffic load among a set of Ingress Controllers and when isolating traffic to a specific Ingress Controller. For example, company A goes to one Ingress Controller and company B to another.

Warning

If you deploy the Keepalived Ingress VIP, do not deploy a non-default Ingress Controller with value HostNetwork for the endpointPublishingStrategy parameter. Doing so might cause issues. Use value NodePort instead of HostNetwork for endpointPublishingStrategy.

Procedure

  1. Edit the router-internal.yaml file:

    # cat router-internal.yaml

    Example output

    apiVersion: v1
    items:
    - apiVersion: operator.openshift.io/v1
      kind: IngressController
      metadata:
        name: sharded
        namespace: openshift-ingress-operator
      spec:
        domain: <apps-sharded.basedomain.example.net>
        nodePlacement:
          nodeSelector:
            matchLabels:
              node-role.kubernetes.io/worker: ""
        namespaceSelector:
          matchLabels:
            type: sharded
      status: {}
    kind: List
    metadata:
      resourceVersion: ""
      selfLink: ""

  2. Apply the Ingress Controller router-internal.yaml file:

    # oc apply -f router-internal.yaml

    The Ingress Controller selects routes in any namespace that is selected by the namespace selector that have the label type: sharded.

6.8.6. Configuring an Ingress Controller to use an internal load balancer

When creating an Ingress Controller on cloud platforms, the Ingress Controller is published by a public cloud load balancer by default. As an administrator, you can create an Ingress Controller that uses an internal cloud load balancer.

Warning

If your cloud provider is Microsoft Azure, you must have at least one public load balancer that points to your nodes. If you do not, all of your nodes will lose egress connectivity to the internet.

Important

If you want to change the scope for an IngressController object, you must delete and then recreate that IngressController object. You cannot change the .spec.endpointPublishingStrategy.loadBalancer.scope parameter after the custom resource (CR) is created.

Figure 6.2. Diagram of LoadBalancer

OpenShift Container Platform Ingress LoadBalancerService endpoint publishing strategy

The preceding graphic shows the following concepts pertaining to OpenShift Container Platform Ingress LoadBalancerService endpoint publishing strategy:

  • You can load load balance externally, using the cloud provider load balancer, or internally, using the OpenShift Ingress Controller Load Balancer.
  • You can use the single IP address of the load balancer and more familiar ports, such as 8080 and 4200 as shown on the cluster depicted in the graphic.
  • Traffic from the external load balancer is directed at the pods, and managed by the load balancer, as depicted in the instance of a down node. See the Kubernetes Services documentation for implementation details.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create an IngressController custom resource (CR) in a file named <name>-ingress-controller.yaml, such as in the following example:

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      namespace: openshift-ingress-operator
      name: <name> 1
    spec:
      domain: <domain> 2
      endpointPublishingStrategy:
        type: LoadBalancerService
        loadBalancer:
          scope: Internal 3
    1
    Replace <name> with a name for the IngressController object.
    2
    Specify the domain for the application published by the controller.
    3
    Specify a value of Internal to use an internal load balancer.
  2. Create the Ingress Controller defined in the previous step by running the following command:

    $ oc create -f <name>-ingress-controller.yaml 1
    1
    Replace <name> with the name of the IngressController object.
  3. Optional: Confirm that the Ingress Controller was created by running the following command:

    $ oc --all-namespaces=true get ingresscontrollers

6.8.7. Configuring the default Ingress Controller for your cluster to be internal

You can configure the default Ingress Controller for your cluster to be internal by deleting and recreating it.

Warning

If your cloud provider is Microsoft Azure, you must have at least one public load balancer that points to your nodes. If you do not, all of your nodes will lose egress connectivity to the internet.

Important

If you want to change the scope for an IngressController object, you must delete and then recreate that IngressController object. You cannot change the .spec.endpointPublishingStrategy.loadBalancer.scope parameter after the custom resource (CR) is created.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Configure the default Ingress Controller for your cluster to be internal by deleting and recreating it.

    $ oc replace --force --wait --filename - <<EOF
    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      namespace: openshift-ingress-operator
      name: default
    spec:
      endpointPublishingStrategy:
        type: LoadBalancerService
        loadBalancer:
          scope: Internal
    EOF

6.8.8. Configuring the route admission policy

Administrators and application developers can run applications in multiple namespaces with the same domain name. This is for organizations where multiple teams develop microservices that are exposed on the same hostname.

Warning

Allowing claims across namespaces should only be enabled for clusters with trust between namespaces, otherwise a malicious user could take over a hostname. For this reason, the default admission policy disallows hostname claims across namespaces.

Prerequisites

  • Cluster administrator privileges.

Procedure

  • Edit the .spec.routeAdmission field of the ingresscontroller resource variable using the following command:

    $ oc -n openshift-ingress-operator patch ingresscontroller/default --patch '{"spec":{"routeAdmission":{"namespaceOwnership":"InterNamespaceAllowed"}}}' --type=merge

    Sample Ingress Controller configuration

    spec:
      routeAdmission:
        namespaceOwnership: InterNamespaceAllowed
    ...

6.8.9. Using wildcard routes

The HAProxy Ingress Controller has support for wildcard routes. The Ingress Operator uses wildcardPolicy to configure the ROUTER_ALLOW_WILDCARD_ROUTES environment variable of the Ingress Controller.

The default behavior of the Ingress Controller is to admit routes with a wildcard policy of None, which is backwards compatible with existing IngressController resources.

Procedure

  1. Configure the wildcard policy.

    1. Use the following command to edit the IngressController resource:

      $ oc edit IngressController
    2. Under spec, set the wildcardPolicy field to WildcardsDisallowed or WildcardsAllowed:

      spec:
        routeAdmission:
          wildcardPolicy: WildcardsDisallowed # or WildcardsAllowed

6.8.10. Using X-Forwarded headers

You configure the HAProxy Ingress Controller to specify a policy for how to handle HTTP headers including Forwarded and X-Forwarded-For. The Ingress Operator uses the HTTPHeaders field to configure the ROUTER_SET_FORWARDED_HEADERS environment variable of the Ingress Controller.

Procedure

  1. Configure the HTTPHeaders field for the Ingress Controller.

    1. Use the following command to edit the IngressController resource:

      $ oc edit IngressController
    2. Under spec, set the HTTPHeaders policy field to Append, Replace, IfNone, or Never:

      apiVersion: operator.openshift.io/v1
      kind: IngressController
      metadata:
        name: default
        namespace: openshift-ingress-operator
      spec:
        httpHeaders:
          forwardedHeaderPolicy: Append
Example use cases

As a cluster administrator, you can:

  • Configure an external proxy that injects the X-Forwarded-For header into each request before forwarding it to an Ingress Controller.

    To configure the Ingress Controller to pass the header through unmodified, you specify the never policy. The Ingress Controller then never sets the headers, and applications receive only the headers that the external proxy provides.

  • Configure the Ingress Controller to pass the X-Forwarded-For header that your external proxy sets on external cluster requests through unmodified.

    To configure the Ingress Controller to set the X-Forwarded-For header on internal cluster requests, which do not go through the external proxy, specify the if-none policy. If an HTTP request already has the header set through the external proxy, then the Ingress Controller preserves it. If the header is absent because the request did not come through the proxy, then the Ingress Controller adds the header.

As an application developer, you can:

  • Configure an application-specific external proxy that injects the X-Forwarded-For header.

    To configure an Ingress Controller to pass the header through unmodified for an application’s Route, without affecting the policy for other Routes, add an annotation haproxy.router.openshift.io/set-forwarded-headers: if-none or haproxy.router.openshift.io/set-forwarded-headers: never on the Route for the application.

    Note

    You can set the haproxy.router.openshift.io/set-forwarded-headers annotation on a per route basis, independent from the globally set value for the Ingress Controller.

6.8.11. Enabling HTTP/2 Ingress connectivity

You can enable transparent end-to-end HTTP/2 connectivity in HAProxy. It allows application owners to make use of HTTP/2 protocol capabilities, including single connection, header compression, binary streams, and more.

You can enable HTTP/2 connectivity for an individual Ingress Controller or for the entire cluster.

To enable the use of HTTP/2 for the connection from the client to HAProxy, a route must specify a custom certificate. A route that uses the default certificate cannot use HTTP/2. This restriction is necessary to avoid problems from connection coalescing, where the client re-uses a connection for different routes that use the same certificate.

The connection from HAProxy to the application pod can use HTTP/2 only for re-encrypt routes and not for edge-terminated or insecure routes. This restriction is because HAProxy uses Application-Level Protocol Negotiation (ALPN), which is a TLS extension, to negotiate the use of HTTP/2 with the back-end. The implication is that end-to-end HTTP/2 is possible with passthrough and re-encrypt and not with insecure or edge-terminated routes.

Warning

Using WebSockets with a re-encrypt route and with HTTP/2 enabled on an Ingress Controller requires WebSocket support over HTTP/2. WebSockets over HTTP/2 is a feature of HAProxy 2.4, which is unsupported in OpenShift Container Platform at this time.

Important

For non-passthrough routes, the Ingress Controller negotiates its connection to the application independently of the connection from the client. This means a client may connect to the Ingress Controller and negotiate HTTP/1.1, and the Ingress Controller may then connect to the application, negotiate HTTP/2, and forward the request from the client HTTP/1.1 connection using the HTTP/2 connection to the application. This poses a problem if the client subsequently tries to upgrade its connection from HTTP/1.1 to the WebSocket protocol, because the Ingress Controller cannot forward WebSocket to HTTP/2 and cannot upgrade its HTTP/2 connection to WebSocket. Consequently, if you have an application that is intended to accept WebSocket connections, it must not allow negotiating the HTTP/2 protocol or else clients will fail to upgrade to the WebSocket protocol.

Procedure

Enable HTTP/2 on a single Ingress Controller.

  • To enable HTTP/2 on an Ingress Controller, enter the oc annotate command:

    $ oc -n openshift-ingress-operator annotate ingresscontrollers/<ingresscontroller_name> ingress.operator.openshift.io/default-enable-http2=true

    Replace <ingresscontroller_name> with the name of the Ingress Controller to annotate.

Enable HTTP/2 on the entire cluster.

  • To enable HTTP/2 for the entire cluster, enter the oc annotate command:

    $ oc annotate ingresses.config/cluster ingress.operator.openshift.io/default-enable-http2=true

6.9. Additional resources

Chapter 7. Configuring the node port service range

As a cluster administrator, you can expand the available node port range. If your cluster uses of a large number of node ports, you might need to increase the number of available ports.

The default port range is 30000-32767. You can never reduce the port range, even if you first expand it beyond the default range.

7.1. Prerequisites

  • Your cluster infrastructure must allow access to the ports that you specify within the expanded range. For example, if you expand the node port range to 30000-32900, the inclusive port range of 32768-32900 must be allowed by your firewall or packet filtering configuration.

7.2. Expanding the node port range

You can expand the node port range for the cluster.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in to the cluster with a user with cluster-admin privileges.

Procedure

  1. To expand the node port range, enter the following command. Replace <port> with the largest port number in the new range.

    $ oc patch network.config.openshift.io cluster --type=merge -p \
      '{
        "spec":
          { "serviceNodePortRange": "30000-<port>" }
      }'

    Example output

    network.config.openshift.io/cluster patched

  2. To confirm that the configuration is active, enter the following command. It can take several minutes for the update to apply.

    $ oc get configmaps -n openshift-kube-apiserver config \
      -o jsonpath="{.data['config\.yaml']}" | \
      grep -Eo '"service-node-port-range":["[[:digit:]]+-[[:digit:]]+"]'

    Example output

    "service-node-port-range":["30000-33000"]

7.3. Additional resources

Chapter 8. Using the Stream Control Transmission Protocol (SCTP) on a bare metal cluster

As a cluster administrator, you can use the Stream Control Transmission Protocol (SCTP) on a cluster.

8.1. Support for Stream Control Transmission Protocol (SCTP) on OpenShift Container Platform

As a cluster administrator, you can enable SCTP on the hosts in the cluster. On Red Hat Enterprise Linux CoreOS (RHCOS), the SCTP module is disabled by default.

SCTP is a reliable message based protocol that runs on top of an IP network.

When enabled, you can use SCTP as a protocol with pods, services, and network policy. A Service object must be defined with the type parameter set to either the ClusterIP or NodePort value.

8.1.1. Example configurations using SCTP protocol

You can configure a pod or service to use SCTP by setting the protocol parameter to the SCTP value in the pod or service object.

In the following example, a pod is configured to use SCTP:

apiVersion: v1
kind: Pod
metadata:
  namespace: project1
  name: example-pod
spec:
  containers:
    - name: example-pod
...
      ports:
        - containerPort: 30100
          name: sctpserver
          protocol: SCTP

In the following example, a service is configured to use SCTP:

apiVersion: v1
kind: Service
metadata:
  namespace: project1
  name: sctpserver
spec:
...
  ports:
    - name: sctpserver
      protocol: SCTP
      port: 30100
      targetPort: 30100
  type: ClusterIP

In the following example, a NetworkPolicy object is configured to apply to SCTP network traffic on port 80 from any pods with a specific label:

kind: NetworkPolicy
apiVersion: networking.k8s.io/v1
metadata:
  name: allow-sctp-on-http
spec:
  podSelector:
    matchLabels:
      role: web
  ingress:
  - ports:
    - protocol: SCTP
      port: 80

8.2. Enabling Stream Control Transmission Protocol (SCTP)

As a cluster administrator, you can load and enable the blacklisted SCTP kernel module on worker nodes in your cluster.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Access to the cluster as a user with the cluster-admin role.

Procedure

  1. Create a file named load-sctp-module.yaml that contains the following YAML definition:

    apiVersion: machineconfiguration.openshift.io/v1
    kind: MachineConfig
    metadata:
      name: load-sctp-module
      labels:
        machineconfiguration.openshift.io/role: worker
    spec:
      config:
        ignition:
          version: 3.1.0
        storage:
          files:
            - path: /etc/modprobe.d/sctp-blacklist.conf
              mode: 0644
              overwrite: true
              contents:
                source: data:,
            - path: /etc/modules-load.d/sctp-load.conf
              mode: 0644
              overwrite: true
              contents:
                source: data:,sctp
  2. To create the MachineConfig object, enter the following command:

    $ oc create -f load-sctp-module.yaml
  3. Optional: To watch the status of the nodes while the MachineConfig Operator applies the configuration change, enter the following command. When the status of a node transitions to Ready, the configuration update is applied.

    $ oc get nodes

8.3. Verifying Stream Control Transmission Protocol (SCTP) is enabled

You can verify that SCTP is working on a cluster by creating a pod with an application that listens for SCTP traffic, associating it with a service, and then connecting to the exposed service.

Prerequisites

  • Access to the Internet from the cluster to install the nc package.
  • Install the OpenShift CLI (oc).
  • Access to the cluster as a user with the cluster-admin role.

Procedure

  1. Create a pod starts an SCTP listener:

    1. Create a file named sctp-server.yaml that defines a pod with the following YAML:

      apiVersion: v1
      kind: Pod
      metadata:
        name: sctpserver
        labels:
          app: sctpserver
      spec:
        containers:
          - name: sctpserver
            image: registry.access.redhat.com/ubi8/ubi
            command: ["/bin/sh", "-c"]
            args:
              ["dnf install -y nc && sleep inf"]
            ports:
              - containerPort: 30102
                name: sctpserver
                protocol: SCTP
    2. Create the pod by entering the following command:

      $ oc create -f sctp-server.yaml
  2. Create a service for the SCTP listener pod.

    1. Create a file named sctp-service.yaml that defines a service with the following YAML:

      apiVersion: v1
      kind: Service
      metadata:
        name: sctpservice
        labels:
          app: sctpserver
      spec:
        type: NodePort
        selector:
          app: sctpserver
        ports:
          - name: sctpserver
            protocol: SCTP
            port: 30102
            targetPort: 30102
    2. To create the service, enter the following command:

      $ oc create -f sctp-service.yaml
  3. Create a pod for the SCTP client.

    1. Create a file named sctp-client.yaml with the following YAML:

      apiVersion: v1
      kind: Pod
      metadata:
        name: sctpclient
        labels:
          app: sctpclient
      spec:
        containers:
          - name: sctpclient
            image: registry.access.redhat.com/ubi8/ubi
            command: ["/bin/sh", "-c"]
            args:
              ["dnf install -y nc && sleep inf"]
    2. To create the Pod object, enter the following command:

      $ oc apply -f sctp-client.yaml
  4. Run an SCTP listener on the server.

    1. To connect to the server pod, enter the following command:

      $ oc rsh sctpserver
    2. To start the SCTP listener, enter the following command:

      $ nc -l 30102 --sctp
  5. Connect to the SCTP listener on the server.

    1. Open a new terminal window or tab in your terminal program.
    2. Obtain the IP address of the sctpservice service. Enter the following command:

      $ oc get services sctpservice -o go-template='{{.spec.clusterIP}}{{"\n"}}'
    3. To connect to the client pod, enter the following command:

      $ oc rsh sctpclient
    4. To start the SCTP client, enter the following command. Replace <cluster_IP> with the cluster IP address of the sctpservice service.

      # nc <cluster_IP> 30102 --sctp

Chapter 9. Configuring PTP hardware

Important

Precision Time Protocol (PTP) hardware is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview/.

9.1. About PTP hardware

OpenShift Container Platform includes the capability to use Precision Time Protocol (PTP)hardware on your nodes. You can configure linuxptp services on nodes in your cluster that have PTP-capable hardware.

Note

The PTP Operator works with PTP-capable devices on clusters provisioned only on bare metal infrastructure.

You can use the OpenShift Container Platform console to install PTP by deploying the PTP Operator. The PTP Operator creates and manages the linuxptp services. The Operator provides the following features:

  • Discovery of the PTP-capable devices in a cluster.
  • Management of the configuration of linuxptp services.

9.2. Automated discovery of PTP network devices

The PTP Operator adds the NodePtpDevice.ptp.openshift.io custom resource definition (CRD) to OpenShift Container Platform. The PTP Operator will search your cluster for PTP capable network devices on each node. The Operator creates and updates a NodePtpDevice custom resource (CR) object for each node that provides a compatible PTP device.

One CR is created for each node, and shares the same name as the node. The .status.devices list provides information about the PTP devices on a node.

The following is an example of a NodePtpDevice CR created by the PTP Operator:

apiVersion: ptp.openshift.io/v1
kind: NodePtpDevice
metadata:
  creationTimestamp: "2019-11-15T08:57:11Z"
  generation: 1
  name: dev-worker-0 1
  namespace: openshift-ptp 2
  resourceVersion: "487462"
  selfLink: /apis/ptp.openshift.io/v1/namespaces/openshift-ptp/nodeptpdevices/dev-worker-0
  uid: 08d133f7-aae2-403f-84ad-1fe624e5ab3f
spec: {}
status:
  devices: 3
  - name: eno1
  - name: eno2
  - name: ens787f0
  - name: ens787f1
  - name: ens801f0
  - name: ens801f1
  - name: ens802f0
  - name: ens802f1
  - name: ens803
1
The value for the name parameter is the same as the name of the node.
2
The CR is created in openshift-ptp namespace by PTP Operator.
3
The devices collection includes a list of all of the PTP capable devices discovered by the Operator on the node.

9.3. Installing the PTP Operator

As a cluster administrator, you can install the PTP Operator using the OpenShift Container Platform CLI or the web console.

9.3.1. CLI: Installing the PTP Operator

As a cluster administrator, you can install the Operator using the CLI.

Prerequisites

  • A cluster installed on bare-metal hardware with nodes that have hardware that supports PTP.
  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. To create a namespace for the PTP Operator, enter the following command:

    $ cat << EOF| oc create -f -
    apiVersion: v1
    kind: Namespace
    metadata:
      name: openshift-ptp
      labels:
        name: openshift-ptp
        openshift.io/cluster-monitoring: "true"
    EOF
  2. To create an Operator group for the Operator, enter the following command:

    $ cat << EOF| oc create -f -
    apiVersion: operators.coreos.com/v1
    kind: OperatorGroup
    metadata:
      name: ptp-operators
      namespace: openshift-ptp
    spec:
      targetNamespaces:
      - openshift-ptp
    EOF
  3. Subscribe to the PTP Operator.

    1. Run the following command to set the OpenShift Container Platform major and minor version as an environment variable, which is used as the channel value in the next step.

      $ OC_VERSION=$(oc version -o yaml | grep openshiftVersion | \
          grep -o '[0-9]*[.][0-9]*' | head -1)
    2. To create a subscription for the PTP Operator, enter the following command:

      $ cat << EOF| oc create -f -
      apiVersion: operators.coreos.com/v1alpha1
      kind: Subscription
      metadata:
        name: ptp-operator-subscription
        namespace: openshift-ptp
      spec:
        channel: "${OC_VERSION}"
        name: ptp-operator
        source: redhat-operators
        sourceNamespace: openshift-marketplace
      EOF
  4. To verify that the Operator is installed, enter the following command:

    $ oc get csv -n openshift-ptp \
      -o custom-columns=Name:.metadata.name,Phase:.status.phase

    Example output

    Name                                        Phase
    ptp-operator.4.4.0-202006160135             Succeeded

9.3.2. Web console: Installing the PTP Operator

As a cluster administrator, you can install the Operator using the web console.

Note

You have to create the namespace and operator group as mentioned in the previous section.

Procedure

  1. Install the PTP Operator using the OpenShift Container Platform web console:

    1. In the OpenShift Container Platform web console, click OperatorsOperatorHub.
    2. Choose PTP Operator from the list of available Operators, and then click Install.
    3. On the Install Operator page, under A specific namespace on the cluster select openshift-ptp. Then, click Install.
  2. Optional: Verify that the PTP Operator installed successfully:

    1. Switch to the OperatorsInstalled Operators page.
    2. Ensure that PTP Operator is listed in the openshift-ptp project with a Status of InstallSucceeded.

      Note

      During installation an Operator might display a Failed status. If the installation later succeeds with an InstallSucceeded message, you can ignore the Failed message.

      If the operator does not appear as installed, to troubleshoot further:

      • Go to the OperatorsInstalled Operators page and inspect the Operator Subscriptions and Install Plans tabs for any failure or errors under Status.
      • Go to the WorkloadsPods page and check the logs for pods in the openshift-ptp project.

9.4. Configuring Linuxptp services

The PTP Operator adds the PtpConfig.ptp.openshift.io custom resource definition (CRD) to OpenShift Container Platform. You can configure the Linuxptp services (ptp4l, phc2sys) by creating a PtpConfig custom resource (CR) object.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.
  • You must have installed the PTP Operator.

Procedure

  1. Create the following PtpConfig CR, and then save the YAML in the <name>-ptp-config.yaml file. Replace <name> with the name for this configuration.

    apiVersion: ptp.openshift.io/v1
    kind: PtpConfig
    metadata:
      name: <name> 1
      namespace: openshift-ptp 2
    spec:
      profile: 3
      - name: "profile1" 4
        interface: "ens787f1" 5
        ptp4lOpts: "-s -2" 6
        phc2sysOpts: "-a -r" 7
      recommend: 8
      - profile: "profile1" 9
        priority: 10 10
        match: 11
        - nodeLabel: "node-role.kubernetes.io/worker" 12
          nodeName: "dev-worker-0" 13
    1
    Specify a name for the PtpConfig CR.
    2
    Specify the namespace where the PTP Operator is installed.
    3
    Specify an array of one or more profile objects.
    4
    Specify the name of a profile object which is used to uniquely identify a profile object.
    5
    Specify the network interface name to use by the ptp4l service, for example ens787f1.
    6
    Specify system config options for the ptp4l service, for example -s -2. This should not include the interface name -i <interface> and service config file -f /etc/ptp4l.conf because these will be automatically appended.
    7
    Specify system config options for the phc2sys service, for example -a -r.
    8
    Specify an array of one or more recommend objects which define rules on how the profile should be applied to nodes.
    9
    Specify the profile object name defined in the profile section.
    10
    Specify the priority with an integer value between 0 and 99. A larger number gets lower priority, so a priority of 99 is lower than a priority of 10. If a node can be matched with multiple profiles according to rules defined in the match field, the profile with the higher priority will be applied to that node.
    11
    Specify match rules with nodeLabel or nodeName.
    12
    Specify nodeLabel with the key of node.Labels from the node object.
    13
    Specify nodeName with node.Name from the node object.
  2. Create the CR by running the following command:

    $ oc create -f <filename> 1
    1
    Replace <filename> with the name of the file you created in the previous step.
  3. Optional: Check that the PtpConfig profile is applied to nodes that match with nodeLabel or nodeName.

    $ oc get pods -n openshift-ptp -o wide

    Example output

    NAME                            READY   STATUS    RESTARTS   AGE   IP               NODE           NOMINATED NODE   READINESS GATES
    linuxptp-daemon-4xkbb           1/1     Running   0          43m   192.168.111.15   dev-worker-0   <none>           <none>
    linuxptp-daemon-tdspf           1/1     Running   0          43m   192.168.111.11   dev-master-0   <none>           <none>
    ptp-operator-657bbb64c8-2f8sj   1/1     Running   0          43m   10.128.0.116     dev-master-0   <none>           <none>
    
    $ oc logs linuxptp-daemon-4xkbb -n openshift-ptp
    I1115 09:41:17.117596 4143292 daemon.go:107] in applyNodePTPProfile
    I1115 09:41:17.117604 4143292 daemon.go:109] updating NodePTPProfile to:
    I1115 09:41:17.117607 4143292 daemon.go:110] ------------------------------------
    I1115 09:41:17.117612 4143292 daemon.go:102] Profile Name: profile1 1
    I1115 09:41:17.117616 4143292 daemon.go:102] Interface: ens787f1    2
    I1115 09:41:17.117620 4143292 daemon.go:102] Ptp4lOpts: -s -2       3
    I1115 09:41:17.117623 4143292 daemon.go:102] Phc2sysOpts: -a -r     4
    I1115 09:41:17.117626 4143292 daemon.go:116] ------------------------------------
    I1115 09:41:18.117934 4143292 daemon.go:186] Starting phc2sys...
    I1115 09:41:18.117985 4143292 daemon.go:187] phc2sys cmd: &{Path:/usr/sbin/phc2sys Args:[/usr/sbin/phc2sys -a -r] Env:[] Dir: Stdin:<nil> Stdout:<nil> Stderr:<nil> ExtraFiles:[] SysProcAttr:<nil> Process:<nil> ProcessState:<nil> ctx:<nil> lookPathErr:<nil> finished:false childFiles:[] closeAfterStart:[] closeAfterWait:[] goroutine:[] errch:<nil> waitDone:<nil>}
    I1115 09:41:19.118175 4143292 daemon.go:186] Starting ptp4l...
    I1115 09:41:19.118209 4143292 daemon.go:187] ptp4l cmd: &{Path:/usr/sbin/ptp4l Args:[/usr/sbin/ptp4l -m -f /etc/ptp4l.conf -i ens787f1 -s -2] Env:[] Dir: Stdin:<nil> Stdout:<nil> Stderr:<nil> ExtraFiles:[] SysProcAttr:<nil> Process:<nil> ProcessState:<nil> ctx:<nil> lookPathErr:<nil> finished:false childFiles:[] closeAfterStart:[] closeAfterWait:[] goroutine:[] errch:<nil> waitDone:<nil>}
    ptp4l[102189.864]: selected /dev/ptp5 as PTP clock
    ptp4l[102189.886]: port 1: INITIALIZING to LISTENING on INIT_COMPLETE
    ptp4l[102189.886]: port 0: INITIALIZING to LISTENING on INIT_COMPLETE

    1
    Profile Name is the name that is applied to node dev-worker-0.
    2
    Interface is the PTP device specified in the profile1 interface field. The ptp4l service runs on this interface.
    3
    Ptp4lOpts are the ptp4l sysconfig options specified in profile1 Ptp4lOpts field.
    4
    Phc2sysOpts are the phc2sys sysconfig options specified in profile1 Phc2sysOpts field.

Chapter 10. Network policy

10.1. About network policy

As a cluster administrator, you can define network policies that restrict traffic to pods in your cluster.

10.1.1. About network policy

In a cluster using a Kubernetes Container Network Interface (CNI) plug-in that supports Kubernetes network policy, network isolation is controlled entirely by NetworkPolicy objects. In OpenShift Container Platform 4.6, OpenShift SDN supports using network policy in its default network isolation mode.

Note

When using the OpenShift SDN cluster network provider, the following limitations apply regarding network policies:

  • Egress network policy as specified by the egress field is not supported.
  • IPBlock is supported by network policy, but without support for except clauses. If you create a policy with an IPBlock section that includes an except clause, the SDN pods log warnings and the entire IPBlock section of that policy is ignored.
Warning

Network policy does not apply to the host network namespace. Pods with host networking enabled are unaffected by network policy rules.

By default, all pods in a project are accessible from other pods and network endpoints. To isolate one or more pods in a project, you can create NetworkPolicy objects in that project to indicate the allowed incoming connections. Project administrators can create and delete NetworkPolicy objects within their own project.

If a pod is matched by selectors in one or more NetworkPolicy objects, then the pod will accept only connections that are allowed by at least one of those NetworkPolicy objects. A pod that is not selected by any NetworkPolicy objects is fully accessible.

The following example NetworkPolicy objects demonstrate supporting different scenarios:

  • Deny all traffic:

    To make a project deny by default, add a NetworkPolicy object that matches all pods but accepts no traffic:

    kind: NetworkPolicy
    apiVersion: networking.k8s.io/v1
    metadata:
      name: deny-by-default
    spec:
      podSelector: {}
      ingress: []
  • Only allow connections from the OpenShift Container Platform Ingress Controller:

    To make a project allow only connections from the OpenShift Container Platform Ingress Controller, add the following NetworkPolicy object.

    apiVersion: networking.k8s.io/v1
    kind: NetworkPolicy
    metadata:
      name: allow-from-openshift-ingress
    spec:
      ingress:
      - from:
        - namespaceSelector:
            matchLabels:
              network.openshift.io/policy-group: ingress
      podSelector: {}
      policyTypes:
      - Ingress
  • Only accept connections from pods within a project:

    To make pods accept connections from other pods in the same project, but reject all other connections from pods in other projects, add the following NetworkPolicy object:

    kind: NetworkPolicy
    apiVersion: networking.k8s.io/v1
    metadata:
      name: allow-same-namespace
    spec:
      podSelector: {}
      ingress:
      - from:
        - podSelector: {}
  • Only allow HTTP and HTTPS traffic based on pod labels:

    To enable only HTTP and HTTPS access to the pods with a specific label (role=frontend in following example), add a NetworkPolicy object similar to the following:

    kind: NetworkPolicy
    apiVersion: networking.k8s.io/v1
    metadata:
      name: allow-http-and-https
    spec:
      podSelector:
        matchLabels:
          role: frontend
      ingress:
      - ports:
        - protocol: TCP
          port: 80
        - protocol: TCP
          port: 443
  • Accept connections by using both namespace and pod selectors:

    To match network traffic by combining namespace and pod selectors, you can use a NetworkPolicy object similar to the following:

    kind: NetworkPolicy
    apiVersion: networking.k8s.io/v1
    metadata:
      name: allow-pod-and-namespace-both
    spec:
      podSelector:
        matchLabels:
          name: test-pods
      ingress:
        - from:
          - namespaceSelector:
              matchLabels:
                project: project_name
            podSelector:
              matchLabels:
                name: test-pods

NetworkPolicy objects are additive, which means you can combine multiple NetworkPolicy objects together to satisfy complex network requirements.

For example, for the NetworkPolicy objects defined in previous samples, you can define both allow-same-namespace and allow-http-and-https policies within the same project. Thus allowing the pods with the label role=frontend, to accept any connection allowed by each policy. That is, connections on any port from pods in the same namespace, and connections on ports 80 and 443 from pods in any namespace.

10.1.2. Optimizations for network policy

Use a network policy to isolate pods that are differentiated from one another by labels within a namespace.

Note

The guidelines for efficient use of network policy rules applies to only the OpenShift SDN cluster network provider.

It is inefficient to apply NetworkPolicy objects to large numbers of individual pods in a single namespace. Pod labels do not exist at the IP address level, so a network policy generates a separate Open vSwitch (OVS) flow rule for every possible link between every pod selected with a podSelector.

For example, if the spec podSelector and the ingress podSelector within a NetworkPolicy object each match 200 pods, then 40,000 (200*200) OVS flow rules are generated. This might slow down a node.

When designing your network policy, refer to the following guidelines:

  • Reduce the number of OVS flow rules by using namespaces to contain groups of pods that need to be isolated.

    NetworkPolicy objects that select a whole namespace, by using the namespaceSelector or an empty podSelector, generate only a single OVS flow rule that matches the VXLAN virtual network ID (VNID) of the namespace.

  • Keep the pods that do not need to be isolated in their original namespace, and move the pods that require isolation into one or more different namespaces.
  • Create additional targeted cross-namespace network policies to allow the specific traffic that you do want to allow from the isolated pods.

10.1.3. Next steps

10.1.4. Additional resources

10.2. Creating a network policy

As a user with the admin role, you can create a network policy for a namespace.

10.2.1. Creating a network policy

To define granular rules describing ingress or egress network traffic allowed for namespaces in your cluster, you can create a network policy.

Note

If you log in with a user with the cluster-admin role, then you can create a network policy in any namespace in the cluster.

Prerequisites

  • Your cluster uses a cluster network provider that supports NetworkPolicy objects, such as the OVN-Kubernetes network provider or the OpenShift SDN network provider with mode: NetworkPolicy set. This mode is the default for OpenShift SDN.
  • You installed the OpenShift CLI (oc).
  • You are logged in to the cluster with a user with admin privileges.
  • You are working in the namespace that the network policy applies to.

Procedure

  1. Create a policy rule:

    1. Create a <policy_name>.yaml file:

      $ touch <policy_name>.yaml

      where:

      <policy_name>
      Specifies the network policy file name.
    2. Define a network policy in the file that you just created, such as in the following examples:

      Deny ingress from all pods in all namespaces

      kind: NetworkPolicy
      apiVersion: networking.k8s.io/v1
      metadata:
        name: deny-by-default
      spec:
        podSelector:
        ingress: []

      Allow ingress from all pods in the same namespace

      kind: NetworkPolicy
      apiVersion: networking.k8s.io/v1
      metadata:
        name: allow-same-namespace
      spec:
        podSelector:
        ingress:
        - from:
          - podSelector: {}

  2. To create the network policy object, enter the following command:

    $ oc apply -f <policy_name>.yaml -n <namespace>

    where:

    <policy_name>
    Specifies the network policy file name.
    <namespace>
    Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.

    Example output

    networkpolicy "default-deny" created

10.2.2. Example NetworkPolicy object

The following annotates an example NetworkPolicy object:

kind: NetworkPolicy
apiVersion: networking.k8s.io/v1
metadata:
  name: allow-27107 1
spec:
  podSelector: 2
    matchLabels:
      app: mongodb
  ingress:
  - from:
    - podSelector: 3
        matchLabels:
          app: app
    ports: 4
    - protocol: TCP
      port: 27017
1
The name of the NetworkPolicy object.
2
A selector that describes the pods to which the policy applies. The policy object can only select pods in the project that defines the NetworkPolicy object.
3
A selector that matches the pods from which the policy object allows ingress traffic. The selector matches pods in the same namespace as the NetworkPolicy.
4
A list of one or more destination ports on which to accept traffic.

10.3. Viewing a network policy

As a user with the admin role, you can view a network policy for a namespace.

10.3.1. Viewing network policies

You can examine the network policies in a namespace.

Note

If you log in with a user with the cluster-admin role, then you can view any network policy in the cluster.

Prerequisites

  • You installed the OpenShift CLI (oc).
  • You are logged in to the cluster with a user with admin privileges.
  • You are working in the namespace where the network policy exists.

Procedure

  • List network policies in a namespace:

    • To view NetworkPolicy objects defined in a namespace, enter the following command:

      $ oc get networkpolicy
    • Optional: To examine a specific network policy, enter the following command:

      $ oc describe networkpolicy <policy_name> -n <namespace>

      where:

      <policy_name>
      Specifies the name of the network policy to inspect.
      <namespace>
      Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.

      For example:

      $ oc describe networkpolicy allow-same-namespace

      Output for oc describe command

      Name:         allow-same-namespace
      Namespace:    ns1
      Created on:   2021-05-24 22:28:56 -0400 EDT
      Labels:       <none>
      Annotations:  <none>
      Spec:
        PodSelector:     <none> (Allowing the specific traffic to all pods in this namespace)
        Allowing ingress traffic:
          To Port: <any> (traffic allowed to all ports)
          From:
            PodSelector: <none>
        Not affecting egress traffic
        Policy Types: Ingress

10.3.2. Example NetworkPolicy object

The following annotates an example NetworkPolicy object:

kind: NetworkPolicy
apiVersion: networking.k8s.io/v1
metadata:
  name: allow-27107 1
spec:
  podSelector: 2
    matchLabels:
      app: mongodb
  ingress:
  - from:
    - podSelector: 3
        matchLabels:
          app: app
    ports: 4
    - protocol: TCP
      port: 27017
1
The name of the NetworkPolicy object.
2
A selector that describes the pods to which the policy applies. The policy object can only select pods in the project that defines the NetworkPolicy object.
3
A selector that matches the pods from which the policy object allows ingress traffic. The selector matches pods in the same namespace as the NetworkPolicy.
4
A list of one or more destination ports on which to accept traffic.

10.4. Editing a network policy

As a user with the admin role, you can edit an existing network policy for a namespace.

10.4.1. Editing a network policy

You can edit a network policy in a namespace.

Note

If you log in with a user with the cluster-admin role, then you can edit a network policy in any namespace in the cluster.

Prerequisites

  • Your cluster uses a cluster network provider that supports NetworkPolicy objects, such as the OVN-Kubernetes network provider or the OpenShift SDN network provider with mode: NetworkPolicy set. This mode is the default for OpenShift SDN.
  • You installed the OpenShift CLI (oc).
  • You are logged in to the cluster with a user with admin privileges.
  • You are working in the namespace where the network policy exists.

Procedure

  1. Optional: To list the network policy objects in a namespace, enter the following command:

    $ oc get networkpolicy -n <namespace>

    where:

    <namespace>
    Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.
  2. Edit the NetworkPolicy object.

    • If you saved the network policy definition in a file, edit the file and make any necessary changes, and then enter the following command.

      $ oc apply -n <namespace> -f <policy_file>.yaml

      where:

      <namespace>
      Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.
      <policy_file>
      Specifies the name of the file containing the network policy.
    • If you need to update the NetworkPolicy object directly, enter the following command:

      $ oc edit networkpolicy <policy_name> -n <namespace>

      where:

      <policy_name>
      Specifies the name of the network policy.
      <namespace>
      Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.
  3. Confirm that the NetworkPolicy object is updated.

    $ oc describe networkpolicy <policy_name> -n <namespace>

    where:

    <policy_name>
    Specifies the name of the network policy.
    <namespace>
    Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.

10.4.2. Example NetworkPolicy object

The following annotates an example NetworkPolicy object:

kind: NetworkPolicy
apiVersion: networking.k8s.io/v1
metadata:
  name: allow-27107 1
spec:
  podSelector: 2
    matchLabels:
      app: mongodb
  ingress:
  - from:
    - podSelector: 3
        matchLabels:
          app: app
    ports: 4
    - protocol: TCP
      port: 27017
1
The name of the NetworkPolicy object.
2
A selector that describes the pods to which the policy applies. The policy object can only select pods in the project that defines the NetworkPolicy object.
3
A selector that matches the pods from which the policy object allows ingress traffic. The selector matches pods in the same namespace as the NetworkPolicy.
4
A list of one or more destination ports on which to accept traffic.

10.4.3. Additional resources

10.5. Deleting a network policy

As a user with the admin role, you can delete a network policy from a namespace.

10.5.1. Deleting a network policy

You can delete a network policy in a namespace.

Note

If you log in with a user with the cluster-admin role, then you can delete any network policy in the cluster.

Prerequisites

  • Your cluster uses a cluster network provider that supports NetworkPolicy objects, such as the OVN-Kubernetes network provider or the OpenShift SDN network provider with mode: NetworkPolicy set. This mode is the default for OpenShift SDN.
  • You installed the OpenShift CLI (oc).
  • You are logged in to the cluster with a user with admin privileges.
  • You are working in the namespace where the network policy exists.

Procedure

  • To delete a NetworkPolicy object, enter the following command:

    $ oc delete networkpolicy <policy_name> -n <namespace>

    where:

    <policy_name>
    Specifies the name of the network policy.
    <namespace>
    Optional: Specifies the namespace if the object is defined in a different namespace than the current namespace.

    Example output

    networkpolicy.networking.k8s.io/allow-same-namespace deleted

10.6. Defining a default network policy for projects

As a cluster administrator, you can modify the new project template to automatically include network policies when you create a new project. If you do not yet have a customized template for new projects, you must first create one.

10.6.1. Modifying the template for new projects

As a cluster administrator, you can modify the default project template so that new projects are created using your custom requirements.

To create your own custom project template:

Procedure

  1. Log in as a user with cluster-admin privileges.
  2. Generate the default project template:

    $ oc adm create-bootstrap-project-template -o yaml > template.yaml
  3. Use a text editor to modify the generated template.yaml file by adding objects or modifying existing objects.
  4. The project template must be created in the openshift-config namespace. Load your modified template:

    $ oc create -f template.yaml -n openshift-config
  5. Edit the project configuration resource using the web console or CLI.

    • Using the web console:

      1. Navigate to the AdministrationCluster Settings page.
      2. Click Global Configuration to view all configuration resources.
      3. Find the entry for Project and click Edit YAML.
    • Using the CLI:

      1. Edit the project.config.openshift.io/cluster resource:

        $ oc edit project.config.openshift.io/cluster
  6. Update the spec section to include the projectRequestTemplate and name parameters, and set the name of your uploaded project template. The default name is project-request.

    Project configuration resource with custom project template

    apiVersion: config.openshift.io/v1
    kind: Project
    metadata:
      ...
    spec:
      projectRequestTemplate:
        name: <template_name>

  7. After you save your changes, create a new project to verify that your changes were successfully applied.

10.6.2. Adding network policies to the new project template

As a cluster administrator, you can add network policies to the default template for new projects. OpenShift Container Platform will automatically create all the NetworkPolicy objects specified in the template in the project.

Prerequisites

  • Your cluster uses a default CNI network provider that supports NetworkPolicy objects, such as the OpenShift SDN network provider with mode: NetworkPolicy set. This mode is the default for OpenShift SDN.
  • You installed the OpenShift CLI (oc).
  • You must log in to the cluster with a user with cluster-admin privileges.
  • You must have created a custom default project template for new projects.

Procedure

  1. Edit the default template for a new project by running the following command:

    $ oc edit template <project_template> -n openshift-config

    Replace <project_template> with the name of the default template that you configured for your cluster. The default template name is project-request.

  2. In the template, add each NetworkPolicy object as an element to the objects parameter. The objects parameter accepts a collection of one or more objects.

    In the following example, the objects parameter collection includes several NetworkPolicy objects.

    Important

    For the OVN-Kubernetes network provider plug-in, when the Ingress Controller is configured to use the HostNetwork endpoint publishing strategy, there is no supported way to apply network policy so that ingress traffic is allowed and all other traffic is denied.

    objects:
    - apiVersion: networking.k8s.io/v1
      kind: NetworkPolicy
      metadata:
        name: allow-from-same-namespace
      spec:
        podSelector: {}
        ingress:
        - from:
          - podSelector: {}
    - apiVersion: networking.k8s.io/v1
      kind: NetworkPolicy
      metadata:
        name: allow-from-openshift-ingress
      spec:
        ingress:
        - from:
          - namespaceSelector:
              matchLabels:
                network.openshift.io/policy-group: ingress
        podSelector: {}
        policyTypes:
        - Ingress
    ...
  3. Optional: Create a new project to confirm that your network policy objects are created successfully by running the following commands:

    1. Create a new project:

      $ oc new-project <project> 1
      1
      Replace <project> with the name for the project you are creating.
    2. Confirm that the network policy objects in the new project template exist in the new project:

      $ oc get networkpolicy
      NAME                           POD-SELECTOR   AGE
      allow-from-openshift-ingress   <none>         7s
      allow-from-same-namespace      <none>         7s

10.7. Configuring multitenant isolation with network policy

As a cluster administrator, you can configure your network policies to provide multitenant network isolation.

Note

If you are using the OpenShift SDN cluster network provider, configuring network policies as described in this section provides network isolation similar to multitenant mode but with network policy mode set.

10.7.1. Configuring multitenant isolation by using network policy

You can configure your project to isolate it from pods and services in other project namespaces.

Prerequisites

  • Your cluster uses a cluster network provider that supports NetworkPolicy objects, such as the OVN-Kubernetes network provider or the OpenShift SDN network provider with mode: NetworkPolicy set. This mode is the default for OpenShift SDN.
  • You installed the OpenShift CLI (oc).
  • You are logged in to the cluster with a user with admin privileges.

Procedure

  1. Create the following NetworkPolicy objects:

    1. A policy named allow-from-openshift-ingress.

      $ cat << EOF| oc create -f -
      apiVersion: networking.k8s.io/v1
      kind: NetworkPolicy
      metadata:
        name: allow-from-openshift-ingress
      spec:
        ingress:
        - from:
          - namespaceSelector:
              matchLabels:
                policy-group.network.openshift.io/ingress: ""
        podSelector: {}
        policyTypes:
        - Ingress
      EOF
    2. A policy named allow-from-openshift-monitoring:

      $ cat << EOF| oc create -f -
      apiVersion: networking.k8s.io/v1
      kind: NetworkPolicy
      metadata:
        name: allow-from-openshift-monitoring
      spec:
        ingress:
        - from:
          - namespaceSelector:
              matchLabels:
                network.openshift.io/policy-group: monitoring
        podSelector: {}
        policyTypes:
        - Ingress
      EOF
    3. A policy named allow-same-namespace:

      $ cat << EOF| oc create -f -
      kind: NetworkPolicy
      apiVersion: networking.k8s.io/v1
      metadata:
        name: allow-same-namespace
      spec:
        podSelector:
        ingress:
        - from:
          - podSelector: {}
      EOF
  2. Optional: To confirm that the network policies exist in your current project, enter the following command:

    $ oc describe networkpolicy

    Example output

    Name:         allow-from-openshift-ingress
    Namespace:    example1
    Created on:   2020-06-09 00:28:17 -0400 EDT
    Labels:       <none>
    Annotations:  <none>
    Spec:
      PodSelector:     <none> (Allowing the specific traffic to all pods in this namespace)
      Allowing ingress traffic:
        To Port: <any> (traffic allowed to all ports)
        From:
          NamespaceSelector: network.openshift.io/policy-group: ingress
      Not affecting egress traffic
      Policy Types: Ingress
    
    
    Name:         allow-from-openshift-monitoring
    Namespace:    example1
    Created on:   2020-06-09 00:29:57 -0400 EDT
    Labels:       <none>
    Annotations:  <none>
    Spec:
      PodSelector:     <none> (Allowing the specific traffic to all pods in this namespace)
      Allowing ingress traffic:
        To Port: <any> (traffic allowed to all ports)
        From:
          NamespaceSelector: network.openshift.io/policy-group: monitoring
      Not affecting egress traffic
      Policy Types: Ingress

10.7.2. Next steps

10.7.3. Additional resources

Chapter 11. Multiple networks

11.1. Understanding multiple networks

In Kubernetes, container networking is delegated to networking plug-ins that implement the Container Network Interface (CNI).

OpenShift Container Platform uses the Multus CNI plug-in to allow chaining of CNI plug-ins. During cluster installation, you configure your default pod network. The default network handles all ordinary network traffic for the cluster. You can define an additional network based on the available CNI plug-ins and attach one or more of these networks to your pods. You can define more than one additional network for your cluster, depending on your needs. This gives you flexibility when you configure pods that deliver network functionality, such as switching or routing.

11.1.1. Usage scenarios for an additional network

You can use an additional network in situations where network isolation is needed, including data plane and control plane separation. Isolating network traffic is useful for the following performance and security reasons:

Performance
You can send traffic on two different planes in order to manage how much traffic is along each plane.
Security
You can send sensitive traffic onto a network plane that is managed specifically for security considerations, and you can separate private data that must not be shared between tenants or customers.

All of the pods in the cluster still use the cluster-wide default network to maintain connectivity across the cluster. Every pod has an eth0 interface that is attached to the cluster-wide pod network. You can view the interfaces for a pod by using the oc exec -it <pod_name> -- ip a command. If you add additional network interfaces that use Multus CNI, they are named net1, net2, …​, netN.

To attach additional network interfaces to a pod, you must create configurations that define how the interfaces are attached. You specify each interface by using a NetworkAttachmentDefinition custom resource (CR). A CNI configuration inside each of these CRs defines how that interface is created.

11.1.2. Additional networks in OpenShift Container Platform

OpenShift Container Platform provides the following CNI plug-ins for creating additional networks in your cluster:

11.2. Configuring an additional network

As a cluster administrator, you can configure an additional network for your cluster. The following network types are supported:

11.2.1. Approaches to managing an additional network

You can manage the life cycle of an additional network by two approaches. Each approach is mutually exclusive and you can only use one approach for managing an additional network at a time. For either approach, the additional network is managed by a Container Network Interface (CNI) plug-in that you configure.

For an additional network, IP addresses are provisioned through an IP Address Management (IPAM) CNI plug-in that you configure as part of the additional network. The IPAM plug-in supports a variety of IP address assignment approaches including DHCP and static assignment.

  • Modify the Cluster Network Operator (CNO) configuration: The CNO automatically creates and manages the NetworkAttachmentDefinition object. In addition to managing the object lifecycle the CNO ensures a DHCP is available for an additional network that uses a DHCP assigned IP address.
  • Applying a YAML manifest: You can manage the additional network directly by creating an NetworkAttachmentDefinition object. This approach allows for the chaining of CNI plug-ins.

11.2.2. Configuration for an additional network attachment

An additional network is configured via the NetworkAttachmentDefinition API in the k8s.cni.cncf.io API group. The configuration for the API is described in the following table:

Table 11.1. NetworkAttachmentDefinition API fields

FieldTypeDescription

metadata.name

string

The name for the additional network.

metadata.namespace

string

The namespace that the object is associated with.

spec.config

string

The CNI plug-in configuration in JSON format.

11.2.2.1. Configuration of an additional network through the Cluster Network Operator

The configuration for an additional network attachment is specified as part of the Cluster Network Operator (CNO) configuration.

The following YAML describes the configuration parameters for managing an additional network with the CNO:

Cluster Network Operator configuration

apiVersion: operator.openshift.io/v1
kind: Network
metadata:
  name: cluster
spec:
  # ...
  additionalNetworks: 1
  - name: <name> 2
    namespace: <namespace> 3
    rawCNIConfig: |- 4
      {
        ...
      }
    type: Raw

1
An array of one or more additional network configurations.
2
The name for the additional network attachment that you are creating. The name must be unique within the specified namespace.
3
The namespace to create the network attachment in. If you do not specify a value, then the default namespace is used.
4
A CNI plug-in configuration in JSON format.

11.2.2.2. Configuration of an additional network from a YAML manifest

The configuration for an additional network is specified from a YAML configuration file, such as in the following example:

apiVersion: k8s.cni.cncf.io/v1
kind: NetworkAttachmentDefinition
metadata:
  name: <name> 1
spec:
  config: |- 2
    {
      ...
    }
1
The name for the additional network attachment that you are creating.
2
A CNI plug-in configuration in JSON format.

11.2.3. Configurations for additional network types

The specific configuration fields for additional networks is described in the following sections.

11.2.3.1. Configuration for a bridge additional network

The following object describes the configuration parameters for the bridge CNI plug-in:

Table 11.2. Bridge CNI plug-in JSON configuration object

FieldTypeDescription

cniVersion

string

The CNI specification version. The 0.3.1 value is required.

name

string

The value for the name parameter you provided previously for the CNO configuration.

type

string

 

bridge

string

Specify the name of the virtual bridge to use. If the bridge interface does not exist on the host, it is created. The default value is cni0.

ipam

object

The configuration object for the IPAM CNI plug-in. The plug-in manages IP address assignment for the attachment definition.

ipMasq

boolean

Set to true to enable IP masquerading for traffic that leaves the virtual network. The source IP address for all traffic is rewritten to the bridge’s IP address. If the bridge does not have an IP address, this setting has no effect. The default value is false.

isGateway

boolean

Set to true to assign an IP address to the bridge. The default value is false.

isDefaultGateway

boolean

Set to true to configure the bridge as the default gateway for the virtual network. The default value is false. If isDefaultGateway is set to true, then isGateway is also set to true automatically.

forceAddress

boolean

Set to true to allow assignment of a previously assigned IP address to the virtual bridge. When set to false, if an IPv4 address or an IPv6 address from overlapping subsets is assigned to the virtual bridge, an error occurs. The default value is false.

hairpinMode

boolean

Set to true to allow the virtual bridge to send an Ethernet frame back through the virtual port it was received on. This mode is also known as reflective relay. The default value is false.

promiscMode

boolean

Set to true to enable promiscuous mode on the bridge. The default value is false.

vlan

string

Specify a virtual LAN (VLAN) tag as an integer value. By default, no VLAN tag is assigned.

mtu

string

Set the maximum transmission unit (MTU) to the specified value. The default value is automatically set by the kernel.

11.2.3.1.1. bridge configuration example

The following example configures an additional network named bridge-net:

{
  "cniVersion": "0.3.1",
  "name": "work-network",
  "type": "bridge",
  "isGateway": true,
  "vlan": 2,
  "ipam": {
    "type": "dhcp"
    }
}

11.2.3.2. Configuration for a host device additional network

Note

Specify your network device by setting only one of the following parameters: device, hwaddr, kernelpath, or pciBusID.

The following object describes the configuration parameters for the host-device CNI plug-in:

Table 11.3. Host device CNI plug-in JSON configuration object

FieldTypeDescription

cniVersion

string

The CNI specification version. The 0.3.1 value is required.

name

string

The value for the name parameter you provided previously for the CNO configuration.

type

string

The name of the CNI plug-in to configure: host-device.

device

string

Optional: The name of the device, such as eth0.

hwaddr

string

Optional: The device hardware MAC address.

kernelpath

string

Optional: The Linux kernel device path, such as /sys/devices/pci0000:00/0000:00:1f.6.

pciBusID

string

Optional: The PCI address of the network device, such as 0000:00:1f.6.

ipam

object

The configuration object for the IPAM CNI plug-in. The plug-in manages IP address assignment for the attachment definition.

11.2.3.2.1. host-device configuration example

The following example configures an additional network named hostdev-net:

{
  "cniVersion": "0.3.1",
  "name": "work-network",
  "type": "host-device",
  "device": "eth1",
  "ipam": {
    "type": "dhcp"
  }
}

11.2.3.3. Configuration for an IPVLAN additional network

The following object describes the configuration parameters for the IPVLAN CNI plug-in:

Table 11.4. IPVLAN CNI plug-in JSON configuration object

FieldTypeDescription

cniVersion

string

The CNI specification version. The 0.3.1 value is required.

name

string

The value for the name parameter you provided previously for the CNO configuration.

type

string

The name of the CNI plug-in to configure: ipvlan.

mode

string

The operating mode for the virtual network. The value must be l2, l3, or l3s. The default value is l2.

master

string

The Ethernet interface to associate with the network attachment. If a master is not specified, the interface for the default network route is used.

mtu

integer

Set the maximum transmission unit (MTU) to the specified value. The default value is automatically set by the kernel.

ipam

object

The configuration object for the IPAM CNI plug-in. The plug-in manages IP address assignment for the attachment definition.

Do not specify dhcp. Configuring IPVLAN with DHCP is not supported because IPVLAN interfaces share the MAC address with the host interface.

11.2.3.3.1. ipvlan configuration example

The following example configures an additional network named ipvlan-net:

{
  "cniVersion": "0.3.1",
  "name": "work-network",
  "type": "ipvlan",
  "master": "eth1",
  "mode": "l3",
  "ipam": {
    "type": "static",
    "addresses": [
       {
         "address": "192.168.10.10/24"
       }
    ]
  }
}

11.2.3.4. Configuration for a MACVLAN additional network

The following object describes the configuration parameters for the macvlan CNI plug-in:

Table 11.5. MACVLAN CNI plug-in JSON configuration object

FieldTypeDescription

cniVersion

string

The CNI specification version. The 0.3.1 value is required.

name

string

The value for the name parameter you provided previously for the CNO configuration.

type

string

The name of the CNI plug-in to configure: macvlan.

mode

string

Configures traffic visibility on the virtual network. Must be either bridge, passthru, private, or vepa. If a value is not provided, the default value is bridge.

master

string

The Ethernet, bonded, or VLAN interface to associate with the virtual interface. If a value is not specified, then the host system’s primary Ethernet interface is used.

mtu

string

The maximum transmission unit (MTU) to the specified value. The default value is automatically set by the kernel.

ipam

object

The configuration object for the IPAM CNI plug-in. The plug-in manages IP address assignment for the attachment definition.

11.2.3.4.1. macvlan configuration example

The following example configures an additional network named macvlan-net:

{
  "cniVersion": "0.3.1",
  "name": "macvlan-net",
  "type": "macvlan",
  "master": "eth1",
  "mode": "bridge",
  "ipam": {
    "type": "dhcp"
    }
}

11.2.4. Configuration of IP address assignment for an additional network

The IP address management (IPAM) Container Network Interface (CNI) plug-in provides IP addresses for other CNI plug-ins.

You can use the following IP address assignment types:

  • Static assignment.
  • Dynamic assignment through a DHCP server. The DHCP server you specify must be reachable from the additional network.
  • Dynamic assignment through the Whereabouts IPAM CNI plug-in.

11.2.4.1. Static IP address assignment configuration

The following table describes the configuration for static IP address assignment:

Table 11.6. ipam static configuration object

FieldTypeDescription

type

string

The IPAM address type. The value static is required.

addresses

array

An array of objects specifying IP addresses to assign to the virtual interface. Both IPv4 and IPv6 IP addresses are supported.

routes

array

An array of objects specifying routes to configure inside the pod.

dns

array

Optional: An array of objects specifying the DNS configuration.

The addresses array requires objects with the following fields:

Table 11.7. ipam.addresses[] array

FieldTypeDescription

address

string

An IP address and network prefix that you specify. For example, if you specify 10.10.21.10/24, then the additional network is assigned an IP address of 10.10.21.10 and the netmask is 255.255.255.0.

gateway

string

The default gateway to route egress network traffic to.

Table 11.8. ipam.routes[] array

FieldTypeDescription

dst

string

The IP address range in CIDR format, such as 192.168.17.0/24 or 0.0.0.0/0 for the default route.

gw

string

The gateway where network traffic is routed.

Table 11.9. ipam.dns object

FieldTypeDescription

nameservers

array

An of array of one or more IP addresses for to send DNS queries to.

domain

array

The default domain to append to a hostname. For example, if the domain is set to example.com, a DNS lookup query for example-host is rewritten as example-host.example.com.

search

array

An array of domain names to append to an unqualified hostname, such as example-host, during a DNS lookup query.

Static IP address assignment configuration example

{
  "ipam": {
    "type": "static",
      "addresses": [
        {
          "address": "191.168.1.7/24"
        }
      ]
  }
}

11.2.4.2. Dynamic IP address (DHCP) assignment configuration

The following JSON describes the configuration for dynamic IP address address assignment with DHCP.

Renewal of DHCP leases

A pod obtains its original DHCP lease when it is created. The lease must be periodically renewed by a minimal DHCP server deployment running on the cluster.

To trigger the deployment of the DHCP server, you must create a shim network attachment by editing the Cluster Network Operator configuration, as in the following example:

Example shim network attachment definition

apiVersion: operator.openshift.io/v1
kind: Network
metadata:
  name: cluster
spec:
  additionalNetworks:
  - name: dhcp-shim
    namespace: default
    type: Raw
    rawCNIConfig: |-
      {
        "name": "dhcp-shim",
        "cniVersion": "0.3.1",
        "type": "bridge",
        "ipam": {
          "type": "dhcp"
        }
      }
  # ...

Table 11.10. ipam DHCP configuration object

FieldTypeDescription

type

string

The IPAM address type. The value dhcp is required.

Dynamic IP address (DHCP) assignment configuration example

{
  "ipam": {
    "type": "dhcp"
  }
}

11.2.4.3. Dynamic IP address assignment configuration with Whereabouts

The Whereabouts CNI plug-in allows the dynamic assignment of an IP address to an additional network without the use of a DHCP server.

The following table describes the configuration for dynamic IP address assignment with Whereabouts:

Table 11.11. ipam whereabouts configuration object

FieldTypeDescription

type

string

The IPAM address type. The value whereabouts is required.

range

string

An IP address and range in CIDR notation. IP addresses are assigned from within this range of addresses.

exclude

array

Optional: A list of zero ore more IP addresses and ranges in CIDR notation. IP addresses within an excluded address range are not assigned.

Dynamic IP address assignment configuration example that uses Whereabouts

{
  "ipam": {
    "type": "whereabouts",
    "range": "192.0.2.192/27",
    "exclude": [
       "192.0.2.192/30",
       "192.0.2.196/32"
    ]
  }
}

11.2.5. Creating an additional network attachment with the Cluster Network Operator

The Cluster Network Operator (CNO) manages additional network definitions. When you specify an additional network to create, the CNO creates the NetworkAttachmentDefinition object automatically.

Important

Do not edit the NetworkAttachmentDefinition objects that the Cluster Network Operator manages. Doing so might disrupt network traffic on your additional network.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. To edit the CNO configuration, enter the following command:

    $ oc edit networks.operator.openshift.io cluster
  2. Modify the CR that you are creating by adding the configuration for the additional network that you are creating, as in the following example CR.

    apiVersion: operator.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      # ...
      additionalNetworks:
      - name: tertiary-net
        namespace: project2
        type: Raw
        rawCNIConfig: |-
          {
            "cniVersion": "0.3.1",
            "name": "tertiary-net",
            "type": "ipvlan",
            "master": "eth1",
            "mode": "l2",
            "ipam": {
              "type": "static",
              "addresses": [
                {
                  "address": "192.168.1.23/24"
                }
              ]
            }
          }
  3. Save your changes and quit the text editor to commit your changes.

Verification

  • Confirm that the CNO created the NetworkAttachmentDefinition object by running the following command. There might be a delay before the CNO creates the object.

    $ oc get network-attachment-definitions -n <namespace>

    where:

    <namespace>
    Specifies the namespace for the network attachment that you added to the CNO configuration.

    Example output

    NAME                 AGE
    test-network-1       14m

11.2.6. Creating an additional network attachment by applying a YAML manifest

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create a YAML file with your additional network configuration, such as in the following example:

    apiVersion: k8s.cni.cncf.io/v1
    kind: NetworkAttachmentDefinition
    metadata:
      name: next-net
    spec:
      config: |-
        {
          "cniVersion": "0.3.1",
          "name": "work-network",
          "type": "host-device",
          "device": "eth1",
          "ipam": {
            "type": "dhcp"
          }
        }
  2. To create the additional network, enter the following command:

    $ oc apply -f <file>.yaml

    where:

    <file>
    Specifies the name of the file contained the YAML manifest.

11.3. Attaching a pod to an additional network

As a cluster user you can attach a pod to an additional network.

11.3.1. Adding a pod to an additional network

You can add a pod to an additional network. The pod continues to send normal cluster-related network traffic over the default network.

When a pod is created additional networks are attached to it. However, if a pod already exists, you cannot attach additional networks to it.

The pod must be in the same namespace as the additional network.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in to the cluster.

Procedure

  1. Add an annotation to the Pod object. Only one of the following annotation formats can be used:

    1. To attach an additional network without any customization, add an annotation with the following format. Replace <network> with the name of the additional network to associate with the pod:

      metadata:
        annotations:
          k8s.v1.cni.cncf.io/networks: <network>[,<network>,...] 1
      1
      To specify more than one additional network, separate each network with a comma. Do not include whitespace between the comma. If you specify the same additional network multiple times, that pod will have multiple network interfaces attached to that network.
    2. To attach an additional network with customizations, add an annotation with the following format:

      metadata:
        annotations:
          k8s.v1.cni.cncf.io/networks: |-
            [
              {
                "name": "<network>", 1
                "namespace": "<namespace>", 2
                "default-route": ["<default-route>"] 3
              }
            ]
      1
      Specify the name of the additional network defined by a NetworkAttachmentDefinition object.
      2
      Specify the namespace where the NetworkAttachmentDefinition object is defined.
      3
      Optional: Specify an override for the default route, such as 192.168.17.1.
  2. To create the pod, enter the following command. Replace <name> with the name of the pod.

    $ oc create -f <name>.yaml
  3. Optional: To Confirm that the annotation exists in the Pod CR, enter the following command, replacing <name> with the name of the pod.

    $ oc get pod <name> -o yaml

    In the following example, the example-pod pod is attached to the net1 additional network:

    $ oc get pod example-pod -o yaml
    apiVersion: v1
    kind: Pod
    metadata:
      annotations:
        k8s.v1.cni.cncf.io/networks: macvlan-bridge
        k8s.v1.cni.cncf.io/networks-status: |- 1
          [{
              "name": "openshift-sdn",
              "interface": "eth0",
              "ips": [
                  "10.128.2.14"
              ],
              "default": true,
              "dns": {}
          },{
              "name": "macvlan-bridge",
              "interface": "net1",
              "ips": [
                  "20.2.2.100"
              ],
              "mac": "22:2f:60:a5:f8:00",
              "dns": {}
          }]
      name: example-pod
      namespace: default
    spec:
      ...
    status:
      ...
    1
    The k8s.v1.cni.cncf.io/networks-status parameter is a JSON array of objects. Each object describes the status of an additional network attached to the pod. The annotation value is stored as a plain text value.

11.3.1.1. Specifying pod-specific addressing and routing options

When attaching a pod to an additional network, you may want to specify further properties about that network in a particular pod. This allows you to change some aspects of routing, as well as specify static IP addresses and MAC addresses. In order to accomplish this, you can use the JSON formatted annotations.

Prerequisites

  • The pod must be in the same namespace as the additional network.
  • Install the OpenShift Command-line Interface (oc).
  • You must log in to the cluster.

Procedure

To add a pod to an additional network while specifying addressing and/or routing options, complete the following steps:

  1. Edit the Pod resource definition. If you are editing an existing Pod resource, run the following command to edit its definition in the default editor. Replace <name> with the name of the Pod resource to edit.

    $ oc edit pod <name>
  2. In the Pod resource definition, add the k8s.v1.cni.cncf.io/networks parameter to the pod metadata mapping. The k8s.v1.cni.cncf.io/networks accepts a JSON string of a list of objects that reference the name of NetworkAttachmentDefinition custom resource (CR) names in addition to specifying additional properties.

    metadata:
      annotations:
        k8s.v1.cni.cncf.io/networks: '[<network>[,<network>,...]]' 1
    1
    Replace <network> with a JSON object as shown in the following examples. The single quotes are required.
  3. In the following example the annotation specifies which network attachment will have the default route, using the default-route parameter.

    apiVersion: v1
    kind: Pod
    metadata:
      name: example-pod
      annotations:
        k8s.v1.cni.cncf.io/networks: '
        {
          "name": "net1"
        },
        {
          "name": "net2", 1
          "default-route": ["192.0.2.1"] 2
        }'
    spec:
      containers:
      - name: example-pod
        command: ["/bin/bash", "-c", "sleep 2000000000000"]
        image: centos/tools
    1
    The name key is the name of the additional network to associate with the pod.
    2
    The default-route key specifies a value of a gateway for traffic to be routed over if no other routing entry is present in the routing table. If more than one default-route key is specified, this will cause the pod to fail to become active.

The default route will cause any traffic that is not specified in other routes to be routed to the gateway.

Important

Setting the default route to an interface other than the default network interface for OpenShift Container Platform may cause traffic that is anticipated for pod-to-pod traffic to be routed over another interface.

To verify the routing properties of a pod, the oc command may be used to execute the ip command within a pod.

$ oc exec -it <pod_name> -- ip route
Note

You may also reference the pod’s k8s.v1.cni.cncf.io/networks-status to see which additional network has been assigned the default route, by the presence of the default-route key in the JSON-formatted list of objects.

To set a static IP address or MAC address for a pod you can use the JSON formatted annotations. This requires you create networks that specifically allow for this functionality. This can be specified in a rawCNIConfig for the CNO.

  1. Edit the CNO CR by running the following command:

    $ oc edit networks.operator.openshift.io cluster

The following YAML describes the configuration parameters for the CNO:

Cluster Network Operator YAML configuration

name: <name> 1
namespace: <namespace> 2
rawCNIConfig: '{ 3
  ...
}'
type: Raw

1
Specify a name for the additional network attachment that you are creating. The name must be unique within the specified namespace.
2
Specify the namespace to create the network attachment in. If you do not specify a value, then the default namespace is used.
3
Specify the CNI plug-in configuration in JSON format, which is based on the following template.

The following object describes the configuration parameters for utilizing static MAC address and IP address using the macvlan CNI plug-in:

macvlan CNI plug-in JSON configuration object using static IP and MAC address

{
  "cniVersion": "0.3.1",
  "name": "<name>", 1
  "plugins": [{ 2
      "type": "macvlan",
      "capabilities": { "ips": true }, 3
      "master": "eth0", 4
      "mode": "bridge",
      "ipam": {
        "type": "static"
      }
    }, {
      "capabilities": { "mac": true }, 5
      "type": "tuning"
    }]
}

1
Specifies the name for the additional network attachment to create. The name must be unique within the specified namespace.
2
Specifies an array of CNI plug-in configurations. The first object specifies a macvlan plug-in configuration and the second object specifies a tuning plug-in configuration.
3
Specifies that a request is made to enable the static IP address functionality of the CNI plug-in runtime configuration capabilities.
4
Specifies the interface that the macvlan plug-in uses.
5
Specifies that a request is made to enable the static MAC address functionality of a CNI plug-in.

The above network attachment can be referenced in a JSON formatted annotation, along with keys to specify which static IP and MAC address will be assigned to a given pod.

Edit the pod with:

$ oc edit pod <name>

macvlan CNI plug-in JSON configuration object using static IP and MAC address

apiVersion: v1
kind: Pod
metadata:
  name: example-pod
  annotations:
    k8s.v1.cni.cncf.io/networks: '[
      {
        "name": "<name>", 1
        "ips": [ "192.0.2.205/24" ], 2
        "mac": "CA:FE:C0:FF:EE:00" 3
      }
    ]'

1
Use the <name> as provided when creating the rawCNIConfig above.
2
Provide an IP address including the subnet mask.
3
Provide the MAC address.
Note

Static IP addresses and MAC addresses do not have to be used at the same time, you may use them individually, or together.

To verify the IP address and MAC properties of a pod with additional networks, use the oc command to execute the ip command within a pod.

$ oc exec -it <pod_name> -- ip a

11.4. Removing a pod from an additional network

As a cluster user you can remove a pod from an additional network.

11.4.1. Removing a pod from an additional network

You can remove a pod from an additional network only by deleting the pod.

Prerequisites

  • An additional network is attached to the pod.
  • Install the OpenShift CLI (oc).
  • Log in to the cluster.

Procedure

  • To delete the pod, enter the following command:

    $ oc delete pod <name> -n <namespace>
    • <name> is the name of the pod.
    • <namespace> is the namespace that contains the pod.

11.5. Editing an additional network

As a cluster administrator you can modify the configuration for an existing additional network.

11.5.1. Modifying an additional network attachment definition

As a cluster administrator, you can make changes to an existing additional network. Any existing pods attached to the additional network will not be updated.

Prerequisites

  • You have configured an additional network for your cluster.
  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

To edit an additional network for your cluster, complete the following steps:

  1. Run the following command to edit the Cluster Network Operator (CNO) CR in your default text editor:

    $ oc edit networks.operator.openshift.io cluster
  2. In the additionalNetworks collection, update the additional network with your changes.
  3. Save your changes and quit the text editor to commit your changes.
  4. Optional: Confirm that the CNO updated the NetworkAttachmentDefinition object by running the following command. Replace <network-name> with the name of the additional network to display. There might be a delay before the CNO updates the NetworkAttachmentDefinition object to reflect your changes.

    $ oc get network-attachment-definitions <network-name> -o yaml

    For example, the following console output displays a NetworkAttachmentDefinition object that is named net1:

    $ oc get network-attachment-definitions net1 -o go-template='{{printf "%s\n" .spec.config}}'
    { "cniVersion": "0.3.1", "type": "macvlan",
    "master": "ens5",
    "mode": "bridge",
    "ipam":       {"type":"static","routes":[{"dst":"0.0.0.0/0","gw":"10.128.2.1"}],"addresses":[{"address":"10.128.2.100/23","gateway":"10.128.2.1"}],"dns":{"nameservers":["172.30.0.10"],"domain":"us-west-2.compute.internal","search":["us-west-2.compute.internal"]}} }

11.6. Removing an additional network

As a cluster administrator you can remove an additional network attachment.

11.6.1. Removing an additional network attachment definition

As a cluster administrator, you can remove an additional network from your OpenShift Container Platform cluster. The additional network is not removed from any pods it is attached to.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

To remove an additional network from your cluster, complete the following steps:

  1. Edit the Cluster Network Operator (CNO) in your default text editor by running the following command:

    $ oc edit networks.operator.openshift.io cluster
  2. Modify the CR by removing the configuration from the additionalNetworks collection for the network attachment definition you are removing.

    apiVersion: operator.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      additionalNetworks: [] 1
    1
    If you are removing the configuration mapping for the only additional network attachment definition in the additionalNetworks collection, you must specify an empty collection.
  3. Save your changes and quit the text editor to commit your changes.
  4. Optional: Confirm that the additional network CR was deleted by running the following command:

    $ oc get network-attachment-definition --all-namespaces

Chapter 12. Hardware networks

12.1. About Single Root I/O Virtualization (SR-IOV) hardware networks

The Single Root I/O Virtualization (SR-IOV) specification is a standard for a type of PCI device assignment that can share a single device with multiple pods.

SR-IOV enables you to segment a compliant network device, recognized on the host node as a physical function (PF), into multiple virtual functions (VFs). The VF is used like any other network device. The SR-IOV device driver for the device determines how the VF is exposed in the container:

  • netdevice driver: A regular kernel network device in the netns of the container
  • vfio-pci driver: A character device mounted in the container

You can use SR-IOV network devices with additional networks on your OpenShift Container Platform cluster installed on bare metal or Red Hat OpenStack Platform (RHOSP) infrastructure for applications that require high bandwidth or low latency.

You can enable SR-IOV on a node by using the following command:

$ oc label node <node_name> feature.node.kubernetes.io/network-sriov.capable="true"

12.1.1. Components that manage SR-IOV network devices

The SR-IOV Network Operator creates and manages the components of the SR-IOV stack. It performs the following functions:

  • Orchestrates discovery and management of SR-IOV network devices
  • Generates NetworkAttachmentDefinition custom resources for the SR-IOV Container Network Interface (CNI)
  • Creates and updates the configuration of the SR-IOV network device plug-in
  • Creates node specific SriovNetworkNodeState custom resources
  • Updates the spec.interfaces field in each SriovNetworkNodeState custom resource

The Operator provisions the following components:

SR-IOV network configuration daemon
A DaemonSet that is deployed on worker nodes when the SR-IOV Operator starts. The daemon is responsible for discovering and initializing SR-IOV network devices in the cluster.
SR-IOV Operator webhook
A dynamic admission controller webhook that validates the Operator custom resource and sets appropriate default values for unset fields.
SR-IOV Network resources injector
A dynamic admission controller webhook that provides functionality for patching Kubernetes pod specifications with requests and limits for custom network resources such as SR-IOV VFs. The SR-IOV network resources injector adds the resource field to only the first container in a pod automatically.
SR-IOV network device plug-in
A device plug-in that discovers, advertises, and allocates SR-IOV network virtual function (VF) resources. Device plug-ins are used in Kubernetes to enable the use of limited resources, typically in physical devices. Device plug-ins give the Kubernetes scheduler awareness of resource availability, so that the scheduler can schedule pods on nodes with sufficient resources.
SR-IOV CNI plug-in
A CNI plug-in that attaches VF interfaces allocated from the SR-IOV device plug-in directly into a pod.
SR-IOV InfiniBand CNI plug-in
A CNI plug-in that attaches InfiniBand (IB) VF interfaces allocated from the SR-IOV device plug-in directly into a pod.
Note

The SR-IOV Network resources injector and SR-IOV Network Operator webhook are enabled by default and can be disabled by editing the default SriovOperatorConfig CR.

12.1.1.1. Supported platforms

The SR-IOV Network Operator is supported on the following platforms:

  • Bare metal
  • Red Hat OpenStack Platform (RHOSP)

12.1.1.2. Supported devices

OpenShift Container Platform supports the following network interface controllers:

Table 12.1. Supported network interface controllers

ManufacturerModelVendor IDDevice ID

Intel

X710

8086

1572

Intel

XXV710

8086

158b

Mellanox

MT27700 Family [ConnectX‑4]

15b3

1013

Mellanox

MT27710 Family [ConnectX‑4 Lx]

15b3

1015

Mellanox

MT27800 Family [ConnectX‑5]

15b3

1017

Mellanox

MT28908 Family [ConnectX‑6]

15b3

101b

12.1.1.3. Automated discovery of SR-IOV network devices

The SR-IOV Network Operator searches your cluster for SR-IOV capable network devices on worker nodes. The Operator creates and updates a SriovNetworkNodeState custom resource (CR) for each worker node that provides a compatible SR-IOV network device.

The CR is assigned the same name as the worker node. The status.interfaces list provides information about the network devices on a node.

Important

Do not modify a SriovNetworkNodeState object. The Operator creates and manages these resources automatically.

12.1.1.3.1. Example SriovNetworkNodeState object

The following YAML is an example of a SriovNetworkNodeState object created by the SR-IOV Network Operator:

An SriovNetworkNodeState object

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovNetworkNodeState
metadata:
  name: node-25 1
  namespace: openshift-sriov-network-operator
  ownerReferences:
  - apiVersion: sriovnetwork.openshift.io/v1
    blockOwnerDeletion: true
    controller: true
    kind: SriovNetworkNodePolicy
    name: default
spec:
  dpConfigVersion: "39824"
status:
  interfaces: 2
  - deviceID: "1017"
    driver: mlx5_core
    mtu: 1500
    name: ens785f0
    pciAddress: "0000:18:00.0"
    totalvfs: 8
    vendor: 15b3
  - deviceID: "1017"
    driver: mlx5_core
    mtu: 1500
    name: ens785f1
    pciAddress: "0000:18:00.1"
    totalvfs: 8
    vendor: 15b3
  - deviceID: 158b
    driver: i40e
    mtu: 1500
    name: ens817f0
    pciAddress: 0000:81:00.0
    totalvfs: 64
    vendor: "8086"
  - deviceID: 158b
    driver: i40e
    mtu: 1500
    name: ens817f1
    pciAddress: 0000:81:00.1
    totalvfs: 64
    vendor: "8086"
  - deviceID: 158b
    driver: i40e
    mtu: 1500
    name: ens803f0
    pciAddress: 0000:86:00.0
    totalvfs: 64
    vendor: "8086"
  syncStatus: Succeeded

1
The value of the name field is the same as the name of the worker node.
2
The interfaces stanza includes a list of all of the SR-IOV devices discovered by the Operator on the worker node.

12.1.1.4. Example use of a virtual function in a pod

You can run a remote direct memory access (RDMA) or a Data Plane Development Kit (DPDK) application in a pod with SR-IOV VF attached.

This example shows a pod using a virtual function (VF) in RDMA mode:

Pod spec that uses RDMA mode

apiVersion: v1
kind: Pod
metadata:
  name: rdma-app
  annotations:
    k8s.v1.cni.cncf.io/networks: sriov-rdma-mlnx
spec:
  containers:
  - name: testpmd
    image: <RDMA_image>
    imagePullPolicy: IfNotPresent
    securityContext:
      runAsUser: 0
      capabilities:
        add: ["IPC_LOCK","SYS_RESOURCE","NET_RAW"]
    command: ["sleep", "infinity"]

The following example shows a pod with a VF in DPDK mode:

Pod spec that uses DPDK mode

apiVersion: v1
kind: Pod
metadata:
  name: dpdk-app
  annotations:
    k8s.v1.cni.cncf.io/networks: sriov-dpdk-net
spec:
  containers:
  - name: testpmd
    image: <DPDK_image>
    securityContext:
      runAsUser: 0
      capabilities:
        add: ["IPC_LOCK","SYS_RESOURCE","NET_RAW"]
    volumeMounts:
    - mountPath: /dev/hugepages
      name: hugepage
    resources:
      limits:
        memory: "1Gi"
        cpu: "2"
        hugepages-1Gi: "4Gi"
      requests:
        memory: "1Gi"
        cpu: "2"
        hugepages-1Gi: "4Gi"
    command: ["sleep", "infinity"]
  volumes:
  - name: hugepage
    emptyDir:
      medium: HugePages

An optional library is available to aid the application running in a container in gathering network information associated with a pod. This library is called 'app-netutil'. See the library’s source code in the app-netutil GitHub repo.

This library is intended to ease the integration of the SR-IOV VFs in DPDK mode into the container. The library provides both a GO API and a C API, as well as examples of using both languages.

There is also a sample Docker image, 'dpdk-app-centos', which can run one of the following DPDK sample applications based on an environmental variable in the pod-spec: l2fwd, l3wd or testpmd. This Docker image provides an example of integrating the 'app-netutil' into the container image itself. The library can also integrate into an init-container which collects the desired data and passes the data to an existing DPDK workload.

12.1.2. Next steps

12.2. Installing the SR-IOV Network Operator

You can install the Single Root I/O Virtualization (SR-IOV) Network Operator on your cluster to manage SR-IOV network devices and network attachments.

12.2.1. Installing SR-IOV Network Operator

As a cluster administrator, you can install the SR-IOV Network Operator by using the OpenShift Container Platform CLI or the web console.

12.2.1.1. CLI: Installing the SR-IOV Network Operator

As a cluster administrator, you can install the Operator using the CLI.

Prerequisites

  • A cluster installed on bare-metal hardware with nodes that have hardware that supports SR-IOV.
  • Install the OpenShift CLI (oc).
  • An account with cluster-admin privileges.

Procedure

  1. To create the openshift-sriov-network-operator namespace, enter the following command:

    $ cat << EOF| oc create -f -
    apiVersion: v1
    kind: Namespace
    metadata:
      name: openshift-sriov-network-operator
    EOF
  2. To create an OperatorGroup CR, enter the following command:

    $ cat << EOF| oc create -f -
    apiVersion: operators.coreos.com/v1
    kind: OperatorGroup
    metadata:
      name: sriov-network-operators
      namespace: openshift-sriov-network-operator
    spec:
      targetNamespaces:
      - openshift-sriov-network-operator
    EOF
  3. Subscribe to the SR-IOV Network Operator.

    1. Run the following command to get the OpenShift Container Platform major and minor version. It is required for the channel value in the next step.

      $ OC_VERSION=$(oc version -o yaml | grep openshiftVersion | \
          grep -o '[0-9]*[.][0-9]*' | head -1)
    2. To create a Subscription CR for the SR-IOV Network Operator, enter the following command:

      $ cat << EOF| oc create -f -
      apiVersion: operators.coreos.com/v1alpha1
      kind: Subscription
      metadata:
        name: sriov-network-operator-subscription
        namespace: openshift-sriov-network-operator
      spec:
        channel: "${OC_VERSION}"
        name: sriov-network-operator
        source: redhat-operators
        sourceNamespace: openshift-marketplace
      EOF
  4. To verify that the Operator is installed, enter the following command:

    $ oc get csv -n openshift-sriov-network-operator \
      -o custom-columns=Name:.metadata.name,Phase:.status.phase

    Example output

    Name                                        Phase
    sriov-network-operator.4.4.0-202006160135   Succeeded

12.2.1.2. Web console: Installing the SR-IOV Network Operator

As a cluster administrator, you can install the Operator using the web console.

Note

You must create the operator group by using the CLI.

Prerequisites

  • A cluster installed on bare-metal hardware with nodes that have hardware that supports SR-IOV.
  • Install the OpenShift CLI (oc).
  • An account with cluster-admin privileges.

Procedure

  1. Create a namespace for the SR-IOV Network Operator:

    1. In the OpenShift Container Platform web console, click AdministrationNamespaces.
    2. Click Create Namespace.
    3. In the Name field, enter openshift-sriov-network-operator, and then click Create.
  2. Install the SR-IOV Network Operator:

    1. In the OpenShift Container Platform web console, click OperatorsOperatorHub.
    2. Select SR-IOV Network Operator from the list of available Operators, and then click Install.
    3. On the Install Operator page, under A specific namespace on the cluster, select openshift-sriov-network-operator.
    4. Click Install.
  3. Verify that the SR-IOV Network Operator is installed successfully:

    1. Navigate to the OperatorsInstalled Operators page.
    2. Ensure that SR-IOV Network Operator is listed in the openshift-sriov-network-operator project with a Status of InstallSucceeded.

      Note

      During installation an Operator might display a Failed status. If the installation later succeeds with an InstallSucceeded message, you can ignore the Failed message.

      If the operator does not appear as installed, to troubleshoot further:

      • Inspect the Operator Subscriptions and Install Plans tabs for any failure or errors under Status.
      • Navigate to the WorkloadsPods page and check the logs for pods in the openshift-sriov-network-operator project.

12.2.2. Next steps

12.3. Configuring the SR-IOV Network Operator

The Single Root I/O Virtualization (SR-IOV) Network Operator manages the SR-IOV network devices and network attachments in your cluster.

12.3.1. Configuring the SR-IOV Network Operator

Important

Modifying the SR-IOV Network Operator configuration is not normally necessary. The default configuration is recommended for most use cases. Complete the steps to modify the relevant configuration only if the default behavior of the Operator is not compatible with your use case.

The SR-IOV Network Operator adds the SriovOperatorConfig.sriovnetwork.openshift.io CustomResourceDefinition resource. The operator automatically creates a SriovOperatorConfig custom resource (CR) named default in the openshift-sriov-network-operator namespace.

Note

The default CR contains the SR-IOV Network Operator configuration for your cluster. To change the operator configuration, you must modify this CR.

The SriovOperatorConfig object provides several fields for configuring the operator:

  • enableInjector allows project administrators to enable or disable the Network Resources Injector daemon set.
  • enableOperatorWebhook allows project administrators to enable or disable the Operator Admission Controller webhook daemon set.
  • configDaemonNodeSelector allows project administrators to schedule the SR-IOV Network Config Daemon on selected nodes.

12.3.1.1. About the Network Resources Injector

The Network Resources Injector is a Kubernetes Dynamic Admission Controller application. It provides the following capabilities:

  • Mutation of resource requests and limits in Pod specification to add an SR-IOV resource name according to an SR-IOV network attachment definition annotation.
  • Mutation of Pod specifications with downward API volume to expose pod annotations and labels to the running container as files under the /etc/podnetinfo path.

By default the Network Resources Injector is enabled by the SR-IOV operator and runs as a daemon set on all control plane nodes (also known as the master nodes). The following is an example of Network Resources Injector pods running in a cluster with three control plane nodes:

$ oc get pods -n openshift-sriov-network-operator

Example output

NAME                                      READY   STATUS    RESTARTS   AGE
network-resources-injector-5cz5p          1/1     Running   0          10m
network-resources-injector-dwqpx          1/1     Running   0          10m
network-resources-injector-lktz5          1/1     Running   0          10m

12.3.1.2. About the SR-IOV Operator admission controller webhook

The SR-IOV Operator Admission Controller webhook is a Kubernetes Dynamic Admission Controller application. It provides the following capabilities:

  • Validation of the SriovNetworkNodePolicy CR when it is created or updated.
  • Mutation of the SriovNetworkNodePolicy CR by setting the default value for the priority and deviceType fields when the CR is created or updated.

By default the SR-IOV Operator Admission Controller webhook is enabled by the operator and runs as a daemon set on all control plane nodes. The following is an example of the Operator Admission Controller webhook pods running in a cluster with three control plane nodes:

$ oc get pods -n openshift-sriov-network-operator

Example output

NAME                                      READY   STATUS    RESTARTS   AGE
operator-webhook-9jkw6                    1/1     Running   0          16m
operator-webhook-kbr5p                    1/1     Running   0          16m
operator-webhook-rpfrl                    1/1     Running   0          16m

12.3.1.3. About custom node selectors

The SR-IOV Network Config daemon discovers and configures the SR-IOV network devices on cluster nodes. By default, it is deployed to all the worker nodes in the cluster. You can use node labels to specify on which nodes the SR-IOV Network Config daemon runs.

12.3.1.4. Disabling or enabling the Network Resources Injector

To disable or enable the Network Resources Injector, which is enabled by default, complete the following procedure.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.
  • You must have installed the SR-IOV Operator.

Procedure

  • Set the enableInjector field. Replace <value> with false to disable the feature or true to enable the feature.

    $ oc patch sriovoperatorconfig default \
      --type=merge -n openshift-sriov-network-operator \
      --patch '{ "spec": { "enableInjector": <value> } }'

12.3.1.5. Disabling or enabling the SR-IOV Operator admission controller webhook

To disable or enable the admission controller webhook, which is enabled by default, complete the following procedure.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.
  • You must have installed the SR-IOV Operator.

Procedure

  • Set the enableOperatorWebhook field. Replace <value> with false to disable the feature or true to enable it:

    $ oc patch sriovoperatorconfig default --type=merge \
      -n openshift-sriov-network-operator \
      --patch '{ "spec": { "enableOperatorWebhook": <value> } }'

12.3.1.6. Configuring a custom NodeSelector for the SR-IOV Network Config daemon

The SR-IOV Network Config daemon discovers and configures the SR-IOV network devices on cluster nodes. By default, it is deployed to all the worker nodes in the cluster. You can use node labels to specify on which nodes the SR-IOV Network Config daemon runs.

To specify the nodes where the SR-IOV Network Config daemon is deployed, complete the following procedure.

Important

When you update the configDaemonNodeSelector field, the SR-IOV Network Config daemon is recreated on each selected node. While the daemon is recreated, cluster users are unable to apply any new SR-IOV Network node policy or create new SR-IOV pods.

Procedure

  • To update the node selector for the operator, enter the following command:

    $ oc patch sriovoperatorconfig default --type=json \
      -n openshift-sriov-network-operator \
      --patch '[{
          "op": "replace",
          "path": "/spec/configDaemonNodeSelector",
          "value": {<node-label>}
        }]'

    Replace <node-label> with a label to apply as in the following example: "node-role.kubernetes.io/worker": "".

12.3.2. Next steps

12.4. Configuring an SR-IOV network device

You can configure a Single Root I/O Virtualization (SR-IOV) device in your cluster.

12.4.1. SR-IOV network node configuration object

You specify the SR-IOV network device configuration for a node by defining an SriovNetworkNodePolicy object. The object is part of the sriovnetwork.openshift.io API group.

The following YAML describes an SriovNetworkNodePolicy object:

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovNetworkNodePolicy
metadata:
  name: <name> 1
  namespace: openshift-sriov-network-operator 2
spec:
  resourceName: <sriov_resource_name> 3
  nodeSelector:
    feature.node.kubernetes.io/network-sriov.capable: "true" 4
  priority: <priority> 5
  mtu: <mtu> 6
  numVfs: <num> 7
  nicSelector: 8
    vendor: "<vendor_code>" 9
    deviceID: "<device_id>" 10
    pfNames: ["<pf_name>", ...] 11
    rootDevices: ["<pci_bus_id>", "..."] 12
  deviceType: <device_type> 13
  isRdma: false 14
  linkType: <link_type> 15
1
The name for the CR object.
2
The namespace where the SR-IOV Operator is installed.
3
The resource name of the SR-IOV device plug-in. You can create multiple SriovNetworkNodePolicy objects for a resource name.
4
The node selector to select which nodes are configured. Only SR-IOV network devices on selected nodes are configured. The SR-IOV Container Network Interface (CNI) plug-in and device plug-in are deployed on only selected nodes.
5
Optional: An integer value between 0 and 99. A smaller number gets higher priority, so a priority of 10 is higher than a priority of 99. The default value is 99.
6
Optional: The maximum transmission unit (MTU) of the virtual function. The maximum MTU value can vary for different NIC models.
7
The number of the virtual functions (VF) to create for the SR-IOV physical network device. For an Intel Network Interface Card (NIC), the number of VFs cannot be larger than the total VFs supported by the device. For a Mellanox NIC, the number of VFs cannot be larger than 128.
8
The nicSelector mapping selects the device for the Operator to configure. You do not have to specify values for all the parameters. It is recommended to identify the network device with enough precision to avoid selecting a device unintentionally. If you specify rootDevices, you must also specify a value for vendor, deviceID, or pfNames. If you specify both pfNames and rootDevices at the same time, ensure that they point to the same device.
9
Optional: The vendor hex code of the SR-IOV network device. The only allowed values are 8086 and 15b3.
10
Optional: The device hex code of SR-IOV network device. The only allowed values are 158b, 1015, and 1017.
11
Optional: An array of one or more physical function (PF) names for the device.
12
An array of one or more PCI bus addresses for the PF of the device. Provide the address in the following format: 0000:02:00.1.
13
Optional: The driver type for the virtual functions. The only allowed values are netdevice and vfio-pci. The default value is netdevice.
Note

For a Mellanox card to work in Data Plane Development Kit (DPDK) mode on bare metal nodes, use the netdevice driver type and set isRdma to true.

14
Optional: Whether to enable remote direct memory access (RDMA) mode. The default value is false.
Note

If the isRDMA parameter is set to true, you can continue to use the RDMA enabled VF as a normal network device. A device can be used in either mode.

15
Optional: The link type for the VFs. You can specify one of the following values: eth or ib. eth is ethernet and ib is InfiniBand. The default value is eth if it is not explicitly set. When linkType is set to ib, isRdma will be set to true by SR-IOV Network Operator webhook automatically. When linkType is set to ib, deviceType should not be set to vfio-pci.

12.4.1.1. SR-IOV network node configuration examples

The following example describes the configuration for an IB device:

Example configuration for an IB device

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovNetworkNodePolicy
metadata:
  name: policy-ib-net-1
  namespace: openshift-sriov-network-operator
spec:
  resourceName: ibnic1
  nodeSelector:
    feature.node.kubernetes.io/network-sriov.capable: "true"
  numVfs: 4
  nicSelector:
    vendor: "15b3"
    deviceID: "101b"
    rootDevices:
      - "0000:19:00.0"
  linkType: ib
  isRdma: true

12.4.1.2. Virtual function (VF) partitioning for SR-IOV devices

In some cases, you might want to split virtual functions (VFs) from the same physical function (PF) into multiple resource pools. For example, you might want some of the VFs to load with the default driver and the remaining VFs load with the vfio-pci driver. In such a deployment, the pfNames selector in your SriovNetworkNodePolicy custom resource (CR) can be used to specify a range of VFs for a pool using the following format: <pfname>#<first_vf>-<last_vf>.

For example, the following YAML shows the selector for an interface named netpf0 with VF 2 through 7:

pfNames: ["netpf0#2-7"]
  • netpf0 is the PF interface name.
  • 2 is the first VF index (0-based) that is included in the range.
  • 7 is the last VF index (0-based) that is included in the range.

You can select VFs from the same PF by using different policy CRs if the following requirements are met:

  • The numVfs value must be identical for policies that select the same PF.
  • The VF index must be in the range of 0 to <numVfs>-1. For example, if you have a policy with numVfs set to 8, then the <first_vf> value must not be smaller than 0, and the <last_vf> must not be larger than 7.
  • The VFs ranges in different policies must not overlap.
  • The <first_vf> must not be larger than the <last_vf>.

The following example illustrates NIC partitioning for an SR-IOV device.

The policy policy-net-1 defines a resource pool net-1 that contains the VF 0 of PF netpf0 with the default VF driver. The policy policy-net-1-dpdk defines a resource pool net-1-dpdk that contains the VF 8 to 15 of PF netpf0 with the vfio VF driver.

Policy policy-net-1:

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovNetworkNodePolicy
metadata:
  name: policy-net-1
  namespace: openshift-sriov-network-operator
spec:
  resourceName: net1
  nodeSelector:
    feature.node.kubernetes.io/network-sriov.capable: "true"
  numVfs: 16
  nicSelector:
    pfNames: ["netpf0#0-0"]
  deviceType: netdevice

Policy policy-net-1-dpdk:

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovNetworkNodePolicy
metadata:
  name: policy-net-1-dpdk
  namespace: openshift-sriov-network-operator
spec:
  resourceName: net1dpdk
  nodeSelector:
    feature.node.kubernetes.io/network-sriov.capable: "true"
  numVfs: 16
  nicSelector:
    pfNames: ["netpf0#8-15"]
  deviceType: vfio-pci

12.4.2. Configuring SR-IOV network devices

The SR-IOV Network Operator adds the SriovNetworkNodePolicy.sriovnetwork.openshift.io CustomResourceDefinition to OpenShift Container Platform. You can configure an SR-IOV network device by creating a SriovNetworkNodePolicy custom resource (CR).

Note

When applying the configuration specified in a SriovNetworkNodePolicy object, the SR-IOV Operator might drain the nodes, and in some cases, reboot nodes.

It might take several minutes for a configuration change to apply.

Prerequisites

  • You installed the OpenShift CLI (oc).
  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the SR-IOV Network Operator.
  • You have enough available nodes in your cluster to handle the evicted workload from drained nodes.
  • You have not selected any control plane nodes for SR-IOV network device configuration.

Procedure

  1. Create an SriovNetworkNodePolicy object, and then save the YAML in the <name>-sriov-node-network.yaml file. Replace <name> with the name for this configuration.
  2. Optional: Label the SR-IOV capable cluster nodes with SriovNetworkNodePolicy.Spec.NodeSelector if they are not already labeled. For more information about labeling nodes, see "Understanding how to update labels on nodes".
  1. Create the SriovNetworkNodePolicy object:

    $ oc create -f <name>-sriov-node-network.yaml

    where <name> specifies the name for this configuration.

    After applying the configuration update, all the pods in sriov-network-operator namespace transition to the Running status.

  2. To verify that the SR-IOV network device is configured, enter the following command. Replace <node_name> with the name of a node with the SR-IOV network device that you just configured.

    $ oc get sriovnetworknodestates -n openshift-sriov-network-operator <node_name> -o jsonpath='{.status.syncStatus}'

12.4.3. Troubleshooting SR-IOV configuration

After following the procedure to configure an SR-IOV network device, the following sections address some error conditions.

To display the state of nodes, run the following command:

$ oc get sriovnetworknodestates -n openshift-sriov-network-operator <node_name>

where: <node_name> specifies the name of a node with an SR-IOV network device.

Error output: Cannot allocate memory

"lastSyncError": "write /sys/bus/pci/devices/0000:3b:00.1/sriov_numvfs: cannot allocate memory"

When a node indicates that it cannot allocate memory, check the following items:

  • Confirm that global SR-IOV settings are enabled in the BIOS for the node.
  • Confirm that VT-d is enabled in the BIOS for the node.

12.4.4. Next steps

12.5. Configuring an SR-IOV Ethernet network attachment

You can configure an Ethernet network attachment for an Single Root I/O Virtualization (SR-IOV) device in the cluster.

12.5.1. Ethernet device configuration object

You can configure an Ethernet network device by defining an SriovNetwork object.

The following YAML describes an SriovNetwork object:

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovNetwork
metadata:
  name: <name> 1
  namespace: openshift-sriov-network-operator 2
spec:
  resourceName: <sriov_resource_name> 3
  networkNamespace: <target_namespace> 4
  vlan: <vlan> 5
  spoofChk: "<spoof_check>" 6
  ipam: |- 7
    {}
  linkState: <link_state> 8
  maxTxRate: <max_tx_rate> 9
  minTxRate: <min_tx_rate> 10
  vlanQoS: <vlan_qos> 11
  trust: "<trust_vf>" 12
  capabilities: <capabilities> 13
1
A name for the object. The SR-IOV Network Operator creates a NetworkAttachmentDefinition object with same name.
2
The namespace where the SR-IOV Network Operator is installed.
3
The value for the spec.resourceName parameter from the SriovNetworkNodePolicy object that defines the SR-IOV hardware for this additional network.
4
The target namespace for the SriovNetwork object. Only pods in the target namespace can attach to the additional network.
5
Optional: A Virtual LAN (VLAN) ID for the additional network. The integer value must be from 0 to 4095. The default value is 0.
6
Optional: The spoof check mode of the VF. The allowed values are the strings "on" and "off".
Important

You must enclose the value you specify in quotes or the object is rejected by the SR-IOV Network Operator.

7
A configuration object for the IPAM CNI plug-in as a YAML block scalar. The plug-in manages IP address assignment for the attachment definition.
8
Optional: The link state of virtual function (VF). Allowed value are enable, disable and auto.
9
Optional: A maximum transmission rate, in Mbps, for the VF.
10
Optional: A minimum transmission rate, in Mbps, for the VF. This value must be less than or equal to the maximum transmission rate.
Note

Intel NICs do not support the minTxRate parameter. For more information, see BZ#1772847.

11
Optional: An IEEE 802.1p priority level for the VF. The default value is 0.
12
Optional: The trust mode of the VF. The allowed values are the strings "on" and "off".
Important

You must enclose the value that you specify in quotes, or the SR-IOV Network Operator rejects the object.

13
Optional: The capabilities to configure for this additional network. You can specify "{ "ips": true }" to enable IP address support or "{ "mac": true }" to enable MAC address support.

12.5.1.1. Configuration of IP address assignment for an additional network

The IP address management (IPAM) Container Network Interface (CNI) plug-in provides IP addresses for other CNI plug-ins.

You can use the following IP address assignment types:

  • Static assignment.
  • Dynamic assignment through a DHCP server. The DHCP server you specify must be reachable from the additional network.
  • Dynamic assignment through the Whereabouts IPAM CNI plug-in.
12.5.1.1.1. Static IP address assignment configuration

The following table describes the configuration for static IP address assignment:

Table 12.2. ipam static configuration object

FieldTypeDescription

type

string

The IPAM address type. The value static is required.

addresses

array

An array of objects specifying IP addresses to assign to the virtual interface. Both IPv4 and IPv6 IP addresses are supported.

routes

array

An array of objects specifying routes to configure inside the pod.

dns

array

Optional: An array of objects specifying the DNS configuration.

The addresses array requires objects with the following fields:

Table 12.3. ipam.addresses[] array

FieldTypeDescription

address

string

An IP address and network prefix that you specify. For example, if you specify 10.10.21.10/24, then the additional network is assigned an IP address of 10.10.21.10 and the netmask is 255.255.255.0.

gateway

string

The default gateway to route egress network traffic to.

Table 12.4. ipam.routes[] array

FieldTypeDescription

dst

string

The IP address range in CIDR format, such as 192.168.17.0/24 or 0.0.0.0/0 for the default route.

gw

string

The gateway where network traffic is routed.

Table 12.5. ipam.dns object

FieldTypeDescription

nameservers

array

An of array of one or more IP addresses for to send DNS queries to.

domain

array

The default domain to append to a hostname. For example, if the domain is set to example.com, a DNS lookup query for example-host is rewritten as example-host.example.com.

search

array

An array of domain names to append to an unqualified hostname, such as example-host, during a DNS lookup query.

Static IP address assignment configuration example

{
  "ipam": {
    "type": "static",
      "addresses": [
        {
          "address": "191.168.1.7/24"
        }
      ]
  }
}

12.5.1.1.2. Dynamic IP address (DHCP) assignment configuration

The following JSON describes the configuration for dynamic IP address address assignment with DHCP.

Renewal of DHCP leases

A pod obtains its original DHCP lease when it is created. The lease must be periodically renewed by a minimal DHCP server deployment running on the cluster.

The SR-IOV Network Operator does not create a DHCP server deployment; The Cluster Network Operator is responsible for creating the minimal DHCP server deployment.

To trigger the deployment of the DHCP server, you must create a shim network attachment by editing the Cluster Network Operator configuration, as in the following example:

Example shim network attachment definition

apiVersion: operator.openshift.io/v1
kind: Network
metadata:
  name: cluster
spec:
  additionalNetworks:
  - name: dhcp-shim
    namespace: default
    type: Raw
    rawCNIConfig: |-
      {
        "name": "dhcp-shim",
        "cniVersion": "0.3.1",
        "type": "bridge",
        "ipam": {
          "type": "dhcp"
        }
      }
  # ...

Table 12.6. ipam DHCP configuration object

FieldTypeDescription

type

string

The IPAM address type. The value dhcp is required.

Dynamic IP address (DHCP) assignment configuration example

{
  "ipam": {
    "type": "dhcp"
  }
}

12.5.1.1.3. Dynamic IP address assignment configuration with Whereabouts

The Whereabouts CNI plug-in allows the dynamic assignment of an IP address to an additional network without the use of a DHCP server.

The following table describes the configuration for dynamic IP address assignment with Whereabouts:

Table 12.7. ipam whereabouts configuration object

FieldTypeDescription

type

string

The IPAM address type. The value whereabouts is required.

range

string

An IP address and range in CIDR notation. IP addresses are assigned from within this range of addresses.

exclude

array

Optional: A list of zero ore more IP addresses and ranges in CIDR notation. IP addresses within an excluded address range are not assigned.

Dynamic IP address assignment configuration example that uses Whereabouts

{
  "ipam": {
    "type": "whereabouts",
    "range": "192.0.2.192/27",
    "exclude": [
       "192.0.2.192/30",
       "192.0.2.196/32"
    ]
  }
}

12.5.2. Configuring SR-IOV additional network

You can configure an additional network that uses SR-IOV hardware by creating a SriovNetwork object. When you create a SriovNetwork object, the SR-IOV Operator automatically creates a NetworkAttachmentDefinition object.

Note

Do not modify or delete a SriovNetwork object if it is attached to any pods in the running state.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create a SriovNetwork object, and then save the YAML in the <name>.yaml file, where <name> is a name for this additional network. The object specification might resemble the following example:

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetwork
    metadata:
      name: attach1
      namespace: openshift-sriov-network-operator
    spec:
      resourceName: net1
      networkNamespace: project2
      ipam: |-
        {
          "type": "host-local",
          "subnet": "10.56.217.0/24",
          "rangeStart": "10.56.217.171",
          "rangeEnd": "10.56.217.181",
          "gateway": "10.56.217.1"
        }
  2. To create the object, enter the following command:

    $ oc create -f <name>.yaml

    where <name> specifies the name of the additional network.

  3. Optional: To confirm that the NetworkAttachmentDefinition object that is associated with the SriovNetwork object that you created in the previous step exists, enter the following command. Replace <namespace> with the networkNamespace you specified in the SriovNetwork object.

    $ oc get net-attach-def -n <namespace>

12.5.3. Next steps

12.5.4. Additional resources

12.6. Configuring an SR-IOV InfiniBand network attachment

You can configure an InfiniBand (IB) network attachment for an Single Root I/O Virtualization (SR-IOV) device in the cluster.

12.6.1. InfiniBand device configuration object

You can configure an InfiniBand (IB) network device by defining an SriovIBNetwork object.

The following YAML describes an SriovIBNetwork object:

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovIBNetwork
metadata:
  name: <name> 1
  namespace: openshift-sriov-network-operator 2
spec:
  resourceName: <sriov_resource_name> 3
  networkNamespace: <target_namespace> 4
  ipam: |- 5
    {}
  linkState: <link_state> 6
  capabilities: <capabilities> 7
1
A name for the object. The SR-IOV Network Operator creates a NetworkAttachmentDefinition object with same name.
2
The namespace where the SR-IOV Operator is installed.
3
The value for the spec.resourceName parameter from the SriovNetworkNodePolicy object that defines the SR-IOV hardware for this additional network.
4
The target namespace for the SriovIBNetwork object. Only pods in the target namespace can attach to the network device.
5
Optional: A configuration object for the IPAM CNI plug-in as a YAML block scalar. The plug-in manages IP address assignment for the attachment definition.
6
Optional: The link state of virtual function (VF). Allowed values are enable, disable and auto.
7
Optional: The capabilities to configure for this network. You can specify "{ "ips": true }" to enable IP address support or "{ "infinibandGUID": true }" to enable IB Global Unique Identifier (GUID) support.

12.6.1.1. Configuration of IP address assignment for an additional network

The IP address management (IPAM) Container Network Interface (CNI) plug-in provides IP addresses for other CNI plug-ins.

You can use the following IP address assignment types:

  • Static assignment.
  • Dynamic assignment through a DHCP server. The DHCP server you specify must be reachable from the additional network.
  • Dynamic assignment through the Whereabouts IPAM CNI plug-in.
12.6.1.1.1. Static IP address assignment configuration

The following table describes the configuration for static IP address assignment:

Table 12.8. ipam static configuration object

FieldTypeDescription

type

string

The IPAM address type. The value static is required.

addresses

array

An array of objects specifying IP addresses to assign to the virtual interface. Both IPv4 and IPv6 IP addresses are supported.

routes

array

An array of objects specifying routes to configure inside the pod.

dns

array

Optional: An array of objects specifying the DNS configuration.

The addresses array requires objects with the following fields:

Table 12.9. ipam.addresses[] array

FieldTypeDescription

address

string

An IP address and network prefix that you specify. For example, if you specify 10.10.21.10/24, then the additional network is assigned an IP address of 10.10.21.10 and the netmask is 255.255.255.0.

gateway

string

The default gateway to route egress network traffic to.

Table 12.10. ipam.routes[] array

FieldTypeDescription

dst

string

The IP address range in CIDR format, such as 192.168.17.0/24 or 0.0.0.0/0 for the default route.

gw

string

The gateway where network traffic is routed.

Table 12.11. ipam.dns object

FieldTypeDescription

nameservers

array

An of array of one or more IP addresses for to send DNS queries to.

domain

array

The default domain to append to a hostname. For example, if the domain is set to example.com, a DNS lookup query for example-host is rewritten as example-host.example.com.

search

array

An array of domain names to append to an unqualified hostname, such as example-host, during a DNS lookup query.

Static IP address assignment configuration example

{
  "ipam": {
    "type": "static",
      "addresses": [
        {
          "address": "191.168.1.7/24"
        }
      ]
  }
}

12.6.1.1.2. Dynamic IP address (DHCP) assignment configuration

The following JSON describes the configuration for dynamic IP address address assignment with DHCP.

Renewal of DHCP leases

A pod obtains its original DHCP lease when it is created. The lease must be periodically renewed by a minimal DHCP server deployment running on the cluster.

To trigger the deployment of the DHCP server, you must create a shim network attachment by editing the Cluster Network Operator configuration, as in the following example:

Example shim network attachment definition

apiVersion: operator.openshift.io/v1
kind: Network
metadata:
  name: cluster
spec:
  additionalNetworks:
  - name: dhcp-shim
    namespace: default
    type: Raw
    rawCNIConfig: |-
      {
        "name": "dhcp-shim",
        "cniVersion": "0.3.1",
        "type": "bridge",
        "ipam": {
          "type": "dhcp"
        }
      }
  # ...

Table 12.12. ipam DHCP configuration object

FieldTypeDescription

type

string

The IPAM address type. The value dhcp is required.

Dynamic IP address (DHCP) assignment configuration example

{
  "ipam": {
    "type": "dhcp"
  }
}

12.6.1.1.3. Dynamic IP address assignment configuration with Whereabouts

The Whereabouts CNI plug-in allows the dynamic assignment of an IP address to an additional network without the use of a DHCP server.

The following table describes the configuration for dynamic IP address assignment with Whereabouts:

Table 12.13. ipam whereabouts configuration object

FieldTypeDescription

type

string

The IPAM address type. The value whereabouts is required.

range

string

An IP address and range in CIDR notation. IP addresses are assigned from within this range of addresses.

exclude

array

Optional: A list of zero ore more IP addresses and ranges in CIDR notation. IP addresses within an excluded address range are not assigned.

Dynamic IP address assignment configuration example that uses Whereabouts

{
  "ipam": {
    "type": "whereabouts",
    "range": "192.0.2.192/27",
    "exclude": [
       "192.0.2.192/30",
       "192.0.2.196/32"
    ]
  }
}

12.6.2. Configuring SR-IOV additional network

You can configure an additional network that uses SR-IOV hardware by creating a SriovIBNetwork object. When you create a SriovIBNetwork object, the SR-IOV Operator automatically creates a NetworkAttachmentDefinition object.

Note

Do not modify or delete a SriovIBNetwork object if it is attached to any pods in the running state.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create a SriovIBNetwork object, and then save the YAML in the <name>.yaml file, where <name> is a name for this additional network. The object specification might resemble the following example:

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovIBNetwork
    metadata:
      name: attach1
      namespace: openshift-sriov-network-operator
    spec:
      resourceName: net1
      networkNamespace: project2
      ipam: |-
        {
          "type": "host-local",
          "subnet": "10.56.217.0/24",
          "rangeStart": "10.56.217.171",
          "rangeEnd": "10.56.217.181",
          "gateway": "10.56.217.1"
        }
  2. To create the object, enter the following command:

    $ oc create -f <name>.yaml

    where <name> specifies the name of the additional network.

  3. Optional: To confirm that the NetworkAttachmentDefinition object that is associated with the SriovIBNetwork object that you created in the previous step exists, enter the following command. Replace <namespace> with the networkNamespace you specified in the SriovIBNetwork object.

    $ oc get net-attach-def -n <namespace>

12.6.3. Next steps

12.6.4. Additional resources

12.7. Adding a pod to an SR-IOV additional network

You can add a pod to an existing Single Root I/O Virtualization (SR-IOV) network.

12.7.1. Runtime configuration for a network attachment

When attaching a pod to an additional network, you can specify a runtime configuration to make specific customizations for the pod. For example, you can request a specific MAC hardware address.

You specify the runtime configuration by setting an annotation in the pod specification. The annotation key is k8s.v1.cni.cncf.io/networks, and it accepts a JSON object that describes the runtime configuration.

12.7.1.1. Runtime configuration for an Ethernet-based SR-IOV attachment

The following JSON describes the runtime configuration options for an Ethernet-based SR-IOV network attachment.

[
  {
    "name": "<name>", 1
    "mac": "<mac_address>", 2
    "ips": ["<cidr_range>"] 3
  }
]
1
The name of the SR-IOV network attachment definition CR.
2
Optional: The MAC address for the SR-IOV device that is allocated from the resource type defined in the SR-IOV network attachment definition CR. To use this feature, you also must specify { "mac": true } in the SriovNetwork object.
3
Optional: IP addresses for the SR-IOV device that is allocated from the resource type defined in the SR-IOV network attachment definition CR. Both IPv4 and IPv6 addresses are supported. To use this feature, you also must specify { "ips": true } in the SriovNetwork object.

Example runtime configuration

apiVersion: v1
kind: Pod
metadata:
  name: sample-pod
  annotations:
    k8s.v1.cni.cncf.io/networks: |-
      [
        {
          "name": "net1",
          "mac": "20:04:0f:f1:88:01",
          "ips": ["192.168.10.1/24", "2001::1/64"]
        }
      ]
spec:
  containers:
  - name: sample-container
    image: <image>
    imagePullPolicy: IfNotPresent
    command: ["sleep", "infinity"]

12.7.1.2. Runtime configuration for an InfiniBand-based SR-IOV attachment

The following JSON describes the runtime configuration options for an InfiniBand-based SR-IOV network attachment.

[
  {
    "name": "<network_attachment>", 1
    "infiniband-guid": "<guid>", 2
    "ips": ["<cidr_range>"] 3
  }
]
1
The name of the SR-IOV network attachment definition CR.
2
The InfiniBand GUID for the SR-IOV device. To use this feature, you also must specify { "infinibandGUID": true } in the SriovIBNetwork object.
3
The IP addresses for the SR-IOV device that is allocated from the resource type defined in the SR-IOV network attachment definition CR. Both IPv4 and IPv6 addresses are supported. To use this feature, you also must specify { "ips": true } in the SriovIBNetwork object.

Example runtime configuration

apiVersion: v1
kind: Pod
metadata:
  name: sample-pod
  annotations:
    k8s.v1.cni.cncf.io/networks: |-
      [
        {
          "name": "ib1",
          "infiniband-guid": "c2:11:22:33:44:55:66:77",
          "ips": ["192.168.10.1/24", "2001::1/64"]
        }
      ]
spec:
  containers:
  - name: sample-container
    image: <image>
    imagePullPolicy: IfNotPresent
    command: ["sleep", "infinity"]

12.7.2. Adding a pod to an additional network

You can add a pod to an additional network. The pod continues to send normal cluster-related network traffic over the default network.

When a pod is created additional networks are attached to it. However, if a pod already exists, you cannot attach additional networks to it.

The pod must be in the same namespace as the additional network.

Note

The SR-IOV Network Resource Injector adds the resource field to the first container in a pod automatically.

If you are using an Intel network interface controller (NIC) in Data Plane Development Kit (DPDK) mode, only the first container in your pod is configured to access the NIC. Your SR-IOV additional network is configured for DPDK mode if the deviceType is set to vfio-pci in the SriovNetworkNodePolicy object.

You can work around this issue by either ensuring that the container that needs access to the NIC is the first container defined in the Pod object or by disabling the Network Resource Injector. For more information, see BZ#1990953.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in to the cluster.
  • Install the SR-IOV Operator.
  • Create either an SriovNetwork object or an SriovIBNetwork object to attach the pod to.

Procedure

  1. Add an annotation to the Pod object. Only one of the following annotation formats can be used:

    1. To attach an additional network without any customization, add an annotation with the following format. Replace <network> with the name of the additional network to associate with the pod:

      metadata:
        annotations:
          k8s.v1.cni.cncf.io/networks: <network>[,<network>,...] 1
      1
      To specify more than one additional network, separate each network with a comma. Do not include whitespace between the comma. If you specify the same additional network multiple times, that pod will have multiple network interfaces attached to that network.
    2. To attach an additional network with customizations, add an annotation with the following format:

      metadata:
        annotations:
          k8s.v1.cni.cncf.io/networks: |-
            [
              {
                "name": "<network>", 1
                "namespace": "<namespace>", 2
                "default-route": ["<default-route>"] 3
              }
            ]
      1
      Specify the name of the additional network defined by a NetworkAttachmentDefinition object.
      2
      Specify the namespace where the NetworkAttachmentDefinition object is defined.
      3
      Optional: Specify an override for the default route, such as 192.168.17.1.
  2. To create the pod, enter the following command. Replace <name> with the name of the pod.

    $ oc create -f <name>.yaml
  3. Optional: To Confirm that the annotation exists in the Pod CR, enter the following command, replacing <name> with the name of the pod.

    $ oc get pod <name> -o yaml

    In the following example, the example-pod pod is attached to the net1 additional network:

    $ oc get pod example-pod -o yaml
    apiVersion: v1
    kind: Pod
    metadata:
      annotations:
        k8s.v1.cni.cncf.io/networks: macvlan-bridge
        k8s.v1.cni.cncf.io/networks-status: |- 1
          [{
              "name": "openshift-sdn",
              "interface": "eth0",
              "ips": [
                  "10.128.2.14"
              ],
              "default": true,
              "dns": {}
          },{
              "name": "macvlan-bridge",
              "interface": "net1",
              "ips": [
                  "20.2.2.100"
              ],
              "mac": "22:2f:60:a5:f8:00",
              "dns": {}
          }]
      name: example-pod
      namespace: default
    spec:
      ...
    status:
      ...
    1
    The k8s.v1.cni.cncf.io/networks-status parameter is a JSON array of objects. Each object describes the status of an additional network attached to the pod. The annotation value is stored as a plain text value.

12.7.3. Creating a non-uniform memory access (NUMA) aligned SR-IOV pod

You can create a NUMA aligned SR-IOV pod by restricting SR-IOV and the CPU resources allocated from the same NUMA node with restricted or single-numa-node Topology Manager polices.

Prerequisites

  • You have installed the OpenShift CLI (oc).
  • You have configured the CPU Manager policy to static. For more information on CPU Manager, see the "Additional resources" section.
  • You have configured the Topology Manager policy to single-numa-node.

    Note

    When single-numa-node is unable to satisfy the request, you can configure the Topology Manager policy to restricted.

Procedure

  1. Create the following SR-IOV pod spec, and then save the YAML in the <name>-sriov-pod.yaml file. Replace <name> with a name for this pod.

    The following example shows an SR-IOV pod spec:

    apiVersion: v1
    kind: Pod
    metadata:
      name: sample-pod
      annotations:
        k8s.v1.cni.cncf.io/networks: <name> 1
    spec:
      containers:
      - name: sample-container
        image: <image> 2
        command: ["sleep", "infinity"]
        resources:
          limits:
            memory: "1Gi" 3
            cpu: "2" 4
          requests:
            memory: "1Gi"
            cpu: "2"
    1
    Replace <name> with the name of the SR-IOV network attachment definition CR.
    2
    Replace <image> with the name of the sample-pod image.
    3
    To create the SR-IOV pod with guaranteed QoS, set memory limits equal to memory requests.
    4
    To create the SR-IOV pod with guaranteed QoS, set cpu limits equals to cpu requests.
  2. Create the sample SR-IOV pod by running the following command:

    $ oc create -f <filename> 1
    1
    Replace <filename> with the name of the file you created in the previous step.
  3. Confirm that the sample-pod is configured with guaranteed QoS.

    $ oc describe pod sample-pod
  4. Confirm that the sample-pod is allocated with exclusive CPUs.

    $ oc exec sample-pod -- cat /sys/fs/cgroup/cpuset/cpuset.cpus
  5. Confirm that the SR-IOV device and CPUs that are allocated for the sample-pod are on the same NUMA node.

    $ oc exec sample-pod -- cat /sys/fs/cgroup/cpuset/cpuset.cpus

12.7.4. Additional resources

12.8. Using high performance multicast

You can use multicast on your Single Root I/O Virtualization (SR-IOV) hardware network.

12.8.1. High performance multicast

The OpenShift SDN default Container Network Interface (CNI) network provider supports multicast between pods on the default network. This is best used for low-bandwidth coordination or service discovery, and not high-bandwidth applications. For applications such as streaming media, like Internet Protocol television (IPTV) and multipoint videoconferencing, you can utilize Single Root I/O Virtualization (SR-IOV) hardware to provide near-native performance.

When using additional SR-IOV interfaces for multicast:

  • Multicast packages must be sent or received by a pod through the additional SR-IOV interface.
  • The physical network which connects the SR-IOV interfaces decides the multicast routing and topology, which is not controlled by OpenShift Container Platform.

12.8.2. Configuring an SR-IOV interface for multicast

The follow procedure creates an example SR-IOV interface for multicast.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  1. Create a SriovNetworkNodePolicy object:

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetworkNodePolicy
    metadata:
      name: policy-example
      namespace: openshift-sriov-network-operator
    spec:
      resourceName: example
      nodeSelector:
        feature.node.kubernetes.io/network-sriov.capable: "true"
      numVfs: 4
      nicSelector:
        vendor: "8086"
        pfNames: ['ens803f0']
        rootDevices: ['0000:86:00.0']
  2. Create a SriovNetwork object:

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetwork
    metadata:
      name: net-example
      namespace: openshift-sriov-network-operator
    spec:
      networkNamespace: default
      ipam: | 1
        {
          "type": "host-local", 2
          "subnet": "10.56.217.0/24",
          "rangeStart": "10.56.217.171",
          "rangeEnd": "10.56.217.181",
          "routes": [
            {"dst": "224.0.0.0/5"},
            {"dst": "232.0.0.0/5"}
          ],
          "gateway": "10.56.217.1"
        }
      resourceName: example
    1 2
    If you choose to configure DHCP as IPAM, ensure that you provision the following default routes through your DHCP server: 224.0.0.0/5 and 232.0.0.0/5. This is to override the static multicast route set by the default network provider.
  3. Create a pod with multicast application:

    apiVersion: v1
    kind: Pod
    metadata:
      name: testpmd
      namespace: default
      annotations:
        k8s.v1.cni.cncf.io/networks: nic1
    spec:
      containers:
      - name: example
        image: rhel7:latest
        securityContext:
          capabilities:
            add: ["NET_ADMIN"] 1
        command: [ "sleep", "infinity"]
    1
    The NET_ADMIN capability is required only if your application needs to assign the multicast IP address to the SR-IOV interface. Otherwise, it can be omitted.

12.9. Using virtual functions (VFs) with DPDK and RDMA modes

You can use Single Root I/O Virtualization (SR-IOV) network hardware with the Data Plane Development Kit (DPDK) and with remote direct memory access (RDMA).

12.9.1. Examples of using virtual functions in DPDK and RDMA modes

Important

The Data Plane Development Kit (DPDK) is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview/.

Important

Remote Direct Memory Access (RDMA) is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview/.

12.9.2. Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.
  • You must have installed the SR-IOV Network Operator.

12.9.3. Example use of virtual function (VF) in DPDK mode with Intel NICs

Procedure

  1. Create the following SriovNetworkNodePolicy object, and then save the YAML in the intel-dpdk-node-policy.yaml file.

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetworkNodePolicy
    metadata:
      name: intel-dpdk-node-policy
      namespace: openshift-sriov-network-operator
    spec:
      resourceName: intelnics
      nodeSelector:
        feature.node.kubernetes.io/network-sriov.capable: "true"
      priority: <priority>
      numVfs: <num>
      nicSelector:
        vendor: "8086"
        deviceID: "158b"
        pfNames: ["<pf_name>", ...]
        rootDevices: ["<pci_bus_id>", "..."]
      deviceType: vfio-pci 1
    1
    Specify the driver type for the virtual functions to vfio-pci.
    Note

    Please refer to the Configuring SR-IOV network devices section for a detailed explanation on each option in SriovNetworkNodePolicy.

    When applying the configuration specified in a SriovNetworkNodePolicy object, the SR-IOV Operator may drain the nodes, and in some cases, reboot nodes. It may take several minutes for a configuration change to apply. Ensure that there are enough available nodes in your cluster to handle the evicted workload beforehand.

    After the configuration update is applied, all the pods in openshift-sriov-network-operator namespace will change to a Running status.

  2. Create the SriovNetworkNodePolicy object by running the following command:

    $ oc create -f intel-dpdk-node-policy.yaml
  3. Create the following SriovNetwork object, and then save the YAML in the intel-dpdk-network.yaml file.

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetwork
    metadata:
      name: intel-dpdk-network
      namespace: openshift-sriov-network-operator
    spec:
      networkNamespace: <target_namespace>
      ipam: "{}" 1
      vlan: <vlan>
      resourceName: intelnics
    1
    Specify an empty object "{}" for the ipam CNI plug-in. DPDK works in userspace mode and does not require an IP address.
    Note

    See the "Configuring SR-IOV additional network" section for a detailed explanation on each option in SriovNetwork.

  4. Create the SriovNetwork object by running the following command:

    $ oc create -f intel-dpdk-network.yaml
  5. Create the following Pod spec, and then save the YAML in the intel-dpdk-pod.yaml file.

    apiVersion: v1
    kind: Pod
    metadata:
      name: dpdk-app
      namespace: <target_namespace> 1
      annotations:
        k8s.v1.cni.cncf.io/networks: intel-dpdk-network
    spec:
      containers:
      - name: testpmd
        image: <DPDK_image> 2
        securityContext:
          runAsUser: 0
          capabilities:
            add: ["IPC_LOCK","SYS_RESOURCE","NET_RAW"] 3
        volumeMounts:
        - mountPath: /dev/hugepages 4
          name: hugepage
        resources:
          limits:
            openshift.io/intelnics: "1" 5
            memory: "1Gi"
            cpu: "4" 6
            hugepages-1Gi: "4Gi" 7
          requests:
            openshift.io/intelnics: "1"
            memory: "1Gi"
            cpu: "4"
            hugepages-1Gi: "4Gi"
        command: ["sleep", "infinity"]
      volumes:
      - name: hugepage
        emptyDir:
          medium: HugePages
    1
    Specify the same target_namespace where the SriovNetwork object intel-dpdk-network is created. If you would like to create the pod in a different namespace, change target_namespace in both the Pod spec and the SriovNetowrk object.
    2
    Specify the DPDK image which includes your application and the DPDK library used by application.
    3
    Specify additional capabilities required by the application inside the container for hugepage allocation, system resource allocation, and network interface access.
    4
    Mount a hugepage volume to the DPDK pod under /dev/hugepages. The hugepage volume is backed by the emptyDir volume type with the medium being Hugepages.
    5
    Optional: Specify the number of DPDK devices allocated to DPDK pod. This resource request and limit, if not explicitly specified, will be automatically added by the SR-IOV network resource injector. The SR-IOV network resource injector is an admission controller component managed by the SR-IOV Operator. It is enabled by default and can be disabled by setting enableInjector option to false in the default SriovOperatorConfig CR.
    6
    Specify the number of CPUs. The DPDK pod usually requires exclusive CPUs to be allocated from the kubelet. This is achieved by setting CPU Manager policy to static and creating a pod with Guaranteed QoS.
    7
    Specify hugepage size hugepages-1Gi or hugepages-2Mi and the quantity of hugepages that will be allocated to the DPDK pod. Configure 2Mi and 1Gi hugepages separately. Configuring 1Gi hugepage requires adding kernel arguments to Nodes. For example, adding kernel arguments default_hugepagesz=1GB, hugepagesz=1G and hugepages=16 will result in 16*1Gi hugepages be allocated during system boot.
  6. Create the DPDK pod by running the following command:

    $ oc create -f intel-dpdk-pod.yaml

12.9.4. Example use of a virtual function in DPDK mode with Mellanox NICs

Procedure

  1. Create the following SriovNetworkNodePolicy object, and then save the YAML in the mlx-dpdk-node-policy.yaml file.

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetworkNodePolicy
    metadata:
      name: mlx-dpdk-node-policy
      namespace: openshift-sriov-network-operator
    spec:
      resourceName: mlxnics
      nodeSelector:
        feature.node.kubernetes.io/network-sriov.capable: "true"
      priority: <priority>
      numVfs: <num>
      nicSelector:
        vendor: "15b3"
        deviceID: "1015" 1
        pfNames: ["<pf_name>", ...]
        rootDevices: ["<pci_bus_id>", "..."]
      deviceType: netdevice 2
      isRdma: true 3
    1
    Specify the device hex code of the SR-IOV network device. The only allowed values for Mellanox cards are 1015, 1017.
    2
    Specify the driver type for the virtual functions to netdevice. Mellanox SR-IOV VF can work in DPDK mode without using the vfio-pci device type. VF device appears as a kernel network interface inside a container.
    3
    Enable RDMA mode. This is required by Mellanox cards to work in DPDK mode.
    Note

    Please refer to Configuring SR-IOV network devices section for detailed explanation on each option in SriovNetworkNodePolicy.

    When applying the configuration specified in a SriovNetworkNodePolicy object, the SR-IOV Operator may drain the nodes, and in some cases, reboot nodes. It may take several minutes for a configuration change to apply. Ensure that there are enough available nodes in your cluster to handle the evicted workload beforehand.

    After the configuration update is applied, all the pods in the openshift-sriov-network-operator namespace will change to a Running status.

  2. Create the SriovNetworkNodePolicy object by running the following command:

    $ oc create -f mlx-dpdk-node-policy.yaml
  3. Create the following SriovNetwork object, and then save the YAML in the mlx-dpdk-network.yaml file.

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetwork
    metadata:
      name: mlx-dpdk-network
      namespace: openshift-sriov-network-operator
    spec:
      networkNamespace: <target_namespace>
      ipam: |- 1
        ...
      vlan: <vlan>
      resourceName: mlxnics
    1
    Specify a configuration object for the ipam CNI plug-in as a YAML block scalar. The plug-in manages IP address assignment for the attachment definition.
    Note

    See the "Configuring SR-IOV additional network" section for a detailed explanation on each option in SriovNetwork.

  4. Create the SriovNetworkNodePolicy object by running the following command:

    $ oc create -f mlx-dpdk-network.yaml
  5. Create the following Pod spec, and then save the YAML in the mlx-dpdk-pod.yaml file.

    apiVersion: v1
    kind: Pod
    metadata:
      name: dpdk-app
      namespace: <target_namespace> 1
      annotations:
        k8s.v1.cni.cncf.io/networks: mlx-dpdk-network
    spec:
      containers:
      - name: testpmd
        image: <DPDK_image> 2
        securityContext:
          runAsUser: 0
          capabilities:
            add: ["IPC_LOCK","SYS_RESOURCE","NET_RAW"] 3
        volumeMounts:
        - mountPath: /dev/hugepages 4
          name: hugepage
        resources:
          limits:
            openshift.io/mlxnics: "1" 5
            memory: "1Gi"
            cpu: "4" 6
            hugepages-1Gi: "4Gi" 7
          requests:
            openshift.io/mlxnics: "1"
            memory: "1Gi"
            cpu: "4"
            hugepages-1Gi: "4Gi"
        command: ["sleep", "infinity"]
      volumes:
      - name: hugepage
        emptyDir:
          medium: HugePages
    1
    Specify the same target_namespace where SriovNetwork object mlx-dpdk-network is created. If you would like to create the pod in a different namespace, change target_namespace in both Pod spec and SriovNetowrk object.
    2
    Specify the DPDK image which includes your application and the DPDK library used by application.
    3
    Specify additional capabilities required by the application inside the container for hugepage allocation, system resource allocation, and network interface access.
    4
    Mount the hugepage volume to the DPDK pod under /dev/hugepages. The hugepage volume is backed by the emptyDir volume type with the medium being Hugepages.
    5
    Optional: Specify the number of DPDK devices allocated to the DPDK pod. This resource request and limit, if not explicitly specified, will be automatically added by SR-IOV network resource injector. The SR-IOV network resource injector is an admission controller component managed by SR-IOV Operator. It is enabled by default and can be disabled by setting the enableInjector option to false in the default SriovOperatorConfig CR.
    6
    Specify the number of CPUs. The DPDK pod usually requires exclusive CPUs be allocated from kubelet. This is achieved by setting CPU Manager policy to static and creating a pod with Guaranteed QoS.
    7
    Specify hugepage size hugepages-1Gi or hugepages-2Mi and the quantity of hugepages that will be allocated to DPDK pod. Configure 2Mi and 1Gi hugepages separately. Configuring 1Gi hugepage requires adding kernel arguments to Nodes.
  6. Create the DPDK pod by running the following command:

    $ oc create -f mlx-dpdk-pod.yaml

12.9.5. Example of a virtual function in RDMA mode with Mellanox NICs

RDMA over Converged Ethernet (RoCE) is the only supported mode when using RDMA on OpenShift Container Platform.

Procedure

  1. Create the following SriovNetworkNodePolicy object, and then save the YAML in the mlx-rdma-node-policy.yaml file.

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetworkNodePolicy
    metadata:
      name: mlx-rdma-node-policy
      namespace: openshift-sriov-network-operator
    spec:
      resourceName: mlxnics
      nodeSelector:
        feature.node.kubernetes.io/network-sriov.capable: "true"
      priority: <priority>
      numVfs: <num>
      nicSelector:
        vendor: "15b3"
        deviceID: "1015" 1
        pfNames: ["<pf_name>", ...]
        rootDevices: ["<pci_bus_id>", "..."]
      deviceType: netdevice 2
      isRdma: true 3
    1
    Specify the device hex code of SR-IOV network device. The only allowed values for Mellanox cards are 1015, 1017.
    2
    Specify the driver type for the virtual functions to netdevice.
    3
    Enable RDMA mode.
    Note

    Please refer to the Configuring SR-IOV network devices section for a detailed explanation on each option in SriovNetworkNodePolicy.

    When applying the configuration specified in a SriovNetworkNodePolicy object, the SR-IOV Operator may drain the nodes, and in some cases, reboot nodes. It may take several minutes for a configuration change to apply. Ensure that there are enough available nodes in your cluster to handle the evicted workload beforehand.

    After the configuration update is applied, all the pods in the openshift-sriov-network-operator namespace will change to a Running status.

  2. Create the SriovNetworkNodePolicy object by running the following command:

    $ oc create -f mlx-rdma-node-policy.yaml
  3. Create the following SriovNetwork object, and then save the YAML in the mlx-rdma-network.yaml file.

    apiVersion: sriovnetwork.openshift.io/v1
    kind: SriovNetwork
    metadata:
      name: mlx-rdma-network
      namespace: openshift-sriov-network-operator
    spec:
      networkNamespace: <target_namespace>
      ipam: |- 1
        ...
      vlan: <vlan>
      resourceName: mlxnics
    1
    Specify a configuration object for the ipam CNI plug-in as a YAML block scalar. The plug-in manages IP address assignment for the attachment definition.
    Note

    See the "Configuring SR-IOV additional network" section for a detailed explanation on each option in SriovNetwork.

  4. Create the SriovNetworkNodePolicy object by running the following command:

    $ oc create -f mlx-rdma-network.yaml
  5. Create the following Pod spec, and then save the YAML in the mlx-rdma-pod.yaml file.

    apiVersion: v1
    kind: Pod
    metadata:
      name: rdma-app
      namespace: <target_namespace> 1
      annotations:
        k8s.v1.cni.cncf.io/networks: mlx-rdma-network
    spec:
      containers:
      - name: testpmd
        image: <RDMA_image> 2
        securityContext:
          runAsUser: 0
          capabilities:
            add: ["IPC_LOCK","SYS_RESOURCE","NET_RAW"] 3
        volumeMounts:
        - mountPath: /dev/hugepages 4
          name: hugepage
        resources:
          limits:
            memory: "1Gi"
            cpu: "4" 5
            hugepages-1Gi: "4Gi" 6
          requests:
            memory: "1Gi"
            cpu: "4"
            hugepages-1Gi: "4Gi"
        command: ["sleep", "infinity"]
      volumes:
      - name: hugepage
        emptyDir:
          medium: HugePages
    1
    Specify the same target_namespace where SriovNetwork object mlx-rdma-network is created. If you would like to create the pod in a different namespace, change target_namespace in both Pod spec and SriovNetowrk object.
    2
    Specify the RDMA image which includes your application and RDMA library used by application.
    3
    Specify additional capabilities required by the application inside the container for hugepage allocation, system resource allocation, and network interface access.
    4
    Mount the hugepage volume to RDMA pod under /dev/hugepages. The hugepage volume is backed by the emptyDir volume type with the medium being Hugepages.
    5
    Specify number of CPUs. The RDMA pod usually requires exclusive CPUs be allocated from the kubelet. This is achieved by setting CPU Manager policy to static and create pod with Guaranteed QoS.
    6
    Specify hugepage size hugepages-1Gi or hugepages-2Mi and the quantity of hugepages that will be allocated to the RDMA pod. Configure 2Mi and 1Gi hugepages separately. Configuring 1Gi hugepage requires adding kernel arguments to Nodes.
  6. Create the RDMA pod by running the following command:

    $ oc create -f mlx-rdma-pod.yaml

12.10. Uninstalling the SR-IOV Network Operator

To uninstall the SR-IOV Network Operator, you must delete any running SR-IOV workloads, uninstall the Operator, and delete the webhooks that the Operator used.

12.10.1. Uninstalling the SR-IOV Network Operator

As a cluster administrator, you can uninstall the SR-IOV Network Operator.

Prerequisites

  • You have access to an OpenShift Container Platform cluster using an account with cluster-admin permissions.
  • You have the SR-IOV Network Operator installed.

Procedure

  1. Delete all SR-IOV custom resources (CRs):

    $ oc delete sriovnetwork -n openshift-sriov-network-operator --all
    $ oc delete sriovnetworknodepolicy -n openshift-sriov-network-operator --all
    $ oc delete sriovibnetwork -n openshift-sriov-network-operator --all
  2. Follow the instructions in the "Deleting Operators from a cluster" section to remove the SR-IOV Network Operator from your cluster.
  3. Delete the SR-IOV custom resource definitions that remain in the cluster after the SR-IOV Network Operator is uninstalled:

    $ oc delete crd sriovibnetworks.sriovnetwork.openshift.io
    $ oc delete crd sriovnetworknodepolicies.sriovnetwork.openshift.io
    $ oc delete crd sriovnetworknodestates.sriovnetwork.openshift.io
    $ oc delete crd sriovnetworkpoolconfigs.sriovnetwork.openshift.io
    $ oc delete crd sriovnetworks.sriovnetwork.openshift.io
    $ oc delete crd sriovoperatorconfigs.sriovnetwork.openshift.io
  4. Delete the SR-IOV webhooks:

    $ oc delete mutatingwebhookconfigurations network-resources-injector-config
    $ oc delete MutatingWebhookConfiguration sriov-operator-webhook-config
    $ oc delete ValidatingWebhookConfiguration sriov-operator-webhook-config
  5. Delete the SR-IOV Network Operator namespace:

    $ oc delete namespace openshift-sriov-network-operator

Additional resources

Chapter 13. OpenShift SDN default CNI network provider

13.1. About the OpenShift SDN default CNI network provider

OpenShift Container Platform uses a software-defined networking (SDN) approach to provide a unified cluster network that enables communication between pods across the OpenShift Container Platform cluster. This pod network is established and maintained by the OpenShift SDN, which configures an overlay network using Open vSwitch (OVS).

13.1.1. OpenShift SDN network isolation modes

OpenShift SDN provides three SDN modes for configuring the pod network:

  • Network policy mode allows project administrators to configure their own isolation policies using NetworkPolicy objects. Network policy is the default mode in OpenShift Container Platform 4.6.
  • Multitenant mode provides project-level isolation for pods and services. Pods from different projects cannot send packets to or receive packets from pods and services of a different project. You can disable isolation for a project, allowing it to send network traffic to all pods and services in the entire cluster and receive network traffic from those pods and services.
  • Subnet mode provides a flat pod network where every pod can communicate with every other pod and service. The network policy mode provides the same functionality as subnet mode.

13.1.2. Supported default CNI network provider feature matrix

OpenShift Container Platform offers two supported choices, OpenShift SDN and OVN-Kubernetes, for the default Container Network Interface (CNI) network provider. The following table summarizes the current feature support for both network providers:

Table 13.1. Default CNI network provider feature comparison

FeatureOpenShift SDNOVN-Kubernetes

Egress IPs

Supported

Supported

Egress firewall [1]

Supported

Supported

Egress router

Supported

Not supported

Kubernetes network policy

Partially supported [2]

Supported

Multicast

Supported

Supported

  1. Egress firewall is also known as egress network policy in OpenShift SDN. This is not the same as network policy egress.
  2. Does not support egress rules and some ipBlock rules.

13.2. Configuring egress IPs for a project

As a cluster administrator, you can configure the OpenShift SDN default Container Network Interface (CNI) network provider to assign one or more egress IP addresses to a project.

13.2.1. Egress IP address assignment for project egress traffic

By configuring an egress IP address for a project, all outgoing external connections from the specified project will share the same, fixed source IP address. External resources can recognize traffic from a particular project based on the egress IP address. An egress IP address assigned to a project is different from the egress router, which is used to send traffic to specific destinations.

Egress IP addresses are implemented as additional IP addresses on the primary network interface of the node and must be in the same subnet as the node’s primary IP address.

Important

Egress IP addresses must not be configured in any Linux network configuration files, such as ifcfg-eth0.

Egress IPs on Amazon Web Services (AWS), Google Cloud Platform (GCP), and Azure are supported only on OpenShift Container Platform version 4.10 and later.

Allowing additional IP addresses on the primary network interface might require extra configuration when using some virtual machine solutions.

You can assign egress IP addresses to namespaces by setting the egressIPs parameter of the NetNamespace object. After an egress IP is associated with a project, OpenShift SDN allows you to assign egress IPs to hosts in two ways:

  • In the automatically assigned approach, an egress IP address range is assigned to a node.
  • In the manually assigned approach, a list of one or more egress IP address is assigned to a node.

Namespaces that request an egress IP address are matched with nodes that can host those egress IP addresses, and then the egress IP addresses are assigned to those nodes. If the egressIPs parameter is set on a NetNamespace object, but no node hosts that egress IP address, then egress traffic from the namespace will be dropped.

High availability of nodes is automatic. If a node that hosts an egress IP address is unreachable and there are nodes that are able to host that egress IP address, then the egress IP address will move to a new node. When the unreachable node comes back online, the egress IP address automatically moves to balance egress IP addresses across nodes.

Important

The following limitations apply when using egress IP addresses with the OpenShift SDN cluster network provider:

  • You cannot use manually assigned and automatically assigned egress IP addresses on the same nodes.
  • If you manually assign egress IP addresses from an IP address range, you must not make that range available for automatic IP assignment.
  • You cannot share egress IP addresses across multiple namespaces using the OpenShift SDN egress IP address implementation. If you need to share IP addresses across namespaces, the OVN-Kubernetes cluster network provider egress IP address implementation allows you to span IP addresses across multiple namespaces.
Note

If you use OpenShift SDN in multitenant mode, you cannot use egress IP addresses with any namespace that is joined to another namespace by the projects that are associated with them. For example, if project1 and project2 are joined by running the oc adm pod-network join-projects --to=project1 project2 command, neither project can use an egress IP address. For more information, see BZ#1645577.

13.2.1.1. Considerations when using automatically assigned egress IP addresses

When using the automatic assignment approach for egress IP addresses the following considerations apply:

  • You set the egressCIDRs parameter of each node’s HostSubnet resource to indicate the range of egress IP addresses that can be hosted by a node. OpenShift Container Platform sets the egressIPs parameter of the HostSubnet resource based on the IP address range you specify.
  • Only a single egress IP address per namespace is supported when using the automatic assignment mode.

If the node hosting the namespace’s egress IP address is unreachable, OpenShift Container Platform will reassign the egress IP address to another node with a compatible egress IP address range. The automatic assignment approach works best for clusters installed in environments with flexibility in associating additional IP addresses with nodes.

13.2.1.2. Considerations when using manually assigned egress IP addresses

This approach is used for clusters where there can be limitations on associating additional IP addresses with nodes such as in public cloud environments.

When using the manual assignment approach for egress IP addresses the following considerations apply:

  • You set the egressIPs parameter of each node’s HostSubnet resource to indicate the IP addresses that can be hosted by a node.
  • Multiple egress IP addresses per namespace are supported.

When a namespace has multiple egress IP addresses, if the node hosting the first egress IP address is unreachable, OpenShift Container Platform will automatically switch to using the next available egress IP address until the first egress IP address is reachable again.

13.2.2. Configuring automatically assigned egress IP addresses for a namespace

In OpenShift Container Platform you can enable automatic assignment of an egress IP address for a specific namespace across one or more nodes.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Update the NetNamespace object with the egress IP address using the following JSON:

     $ oc patch netnamespace <project_name> --type=merge -p \ 1
      '{
        "egressIPs": [
          "<ip_address>" 2
        ]
      }'
    1
    Specify the name of the project.
    2
    Specify a single egress IP address. Using multiple IP addresses is not supported.

    For example, to assign project1 to an IP address of 192.168.1.100 and project2 to an IP address of 192.168.1.101:

    $ oc patch netnamespace project1 --type=merge -p \
      '{"egressIPs": ["192.168.1.100"]}'
    $ oc patch netnamespace project2 --type=merge -p \
      '{"egressIPs": ["192.168.1.101"]}'
    Note

    Because OpenShift SDN manages the NetNamespace object, you can make changes only by modifying the existing NetNamespace object. Do not create a new NetNamespace object.

  2. Indicate which nodes can host egress IP addresses by setting the egressCIDRs parameter for each host using the following JSON:

    $ oc patch hostsubnet <node_name> --type=merge -p \ 1
      '{
        "egressCIDRs": [
          "<ip_address_range_1>", "<ip_address_range_2>" 2
        ]
      }'
    1
    Specify a node name.
    2
    Specify one or more IP address ranges in CIDR format.

    For example, to set node1 and node2 to host egress IP addresses in the range 192.168.1.0 to 192.168.1.255:

    $ oc patch hostsubnet node1 --type=merge -p \
      '{"egressCIDRs": ["192.168.1.0/24"]}'
    $ oc patch hostsubnet node2 --type=merge -p \
      '{"egressCIDRs": ["192.168.1.0/24"]}'

    OpenShift Container Platform automatically assigns specific egress IP addresses to available nodes in a balanced way. In this case, it assigns the egress IP address 192.168.1.100 to node1 and the egress IP address 192.168.1.101 to node2 or vice versa.

13.2.3. Configuring manually assigned egress IP addresses for a namespace

In OpenShift Container Platform you can associate one or more egress IP addresses with a namespace.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Update the NetNamespace object by specifying the following JSON object with the desired IP addresses:

    $ oc patch netnamespace <project> --type=merge -p \ 1
      '{
        "egressIPs": [ 2
          "<ip_address>"
          ]
      }'
    1
    Specify the name of the project.
    2
    Specify one or more egress IP addresses. The egressIPs parameter is an array.

    For example, to assign the project1 project to an IP address of 192.168.1.100:

    $ oc patch netnamespace project1 --type=merge \
      -p '{"egressIPs": ["192.168.1.100"]}'

    You can set egressIPs to two or more IP addresses on different nodes to provide high availability. If multiple egress IP addresses are set, pods use the first IP in the list for egress, but if the node hosting that IP address fails, pods switch to using the next IP in the list after a short delay.

    Note

    Because OpenShift SDN manages the NetNamespace object, you can make changes only by modifying the existing NetNamespace object. Do not create a new NetNamespace object.

  2. Manually assign the egress IP to the node hosts. Set the egressIPs parameter on the HostSubnet object on the node host. Using the following JSON, include as many IPs as you want to assign to that node host:

    $ oc patch hostsubnet <node_name> --type=merge -p \ 1
      '{
        "egressIPs": [ 2
          "<ip_address_1>",
          "<ip_address_N>"
          ]
      }'
    1
    Specify the name of the node.
    2
    Specify one or more egress IP addresses. The egressIPs field is an array.

    For example, to specify that node1 should have the egress IPs 192.168.1.100, 192.168.1.101, and 192.168.1.102:

    $ oc patch hostsubnet node1 --type=merge -p \
      '{"egressIPs": ["192.168.1.100", "192.168.1.101", "192.168.1.102"]}'

    In the previous example, all egress traffic for project1 will be routed to the node hosting the specified egress IP, and then connected (using NAT) to that IP address.

13.3. Configuring an egress firewall for a project

As a cluster administrator, you can create an egress firewall for a project that restricts egress traffic leaving your OpenShift Container Platform cluster.

13.3.1. How an egress firewall works in a project

As a cluster administrator, you can use an egress firewall to limit the external hosts that some or all pods can access from within the cluster. An egress firewall supports the following scenarios:

  • A pod can only connect to internal hosts and cannot initiate connections to the public Internet.
  • A pod can only connect to the public Internet and cannot initiate connections to internal hosts that are outside the OpenShift Container Platform cluster.
  • A pod cannot reach specified internal subnets or hosts outside the OpenShift Container Platform cluster.
  • A pod can connect to only specific external hosts.

For example, you can allow one project access to a specified IP range but deny the same access to a different project. Or you can restrict application developers from updating from Python pip mirrors, and force updates to come only from approved sources.

You configure an egress firewall policy by creating an EgressNetworkPolicy custom resource (CR) object. The egress firewall matches network traffic that meets any of the following criteria:

  • An IP address range in CIDR format
  • A DNS name that resolves to an IP address
Important

If your egress firewall includes a deny rule for 0.0.0.0/0, access to your OpenShift Container Platform API servers is blocked. To ensure that pods can continue to access the OpenShift Container Platform API servers, you must include the IP address range that the API servers listen on in your egress firewall rules, as in the following example:

apiVersion: network.openshift.io/v1
kind: EgressNetworkPolicy
metadata:
  name: default
  namespace: <namespace> 1
spec:
  egress:
  - to:
      cidrSelector: <api_server_address_range> 2
    type: Allow
# ...
  - to:
      cidrSelector: 0.0.0.0/0 3
    type: Deny
1
The namespace for the egress firewall.
2
The IP address range that includes your OpenShift Container Platform API servers.
3
A global deny rule prevents access to the OpenShift Container Platform API servers.

To find the IP address for your API servers, run oc get ep kubernetes -n default.

For more information, see BZ#1988324.

Important

You must have OpenShift SDN configured to use either the network policy or multitenant mode to configure an egress firewall.

If you use network policy mode, an egress firewall is compatible with only one policy per namespace and will not work with projects that share a network, such as global projects.

Warning

Egress firewall rules do not apply to traffic that goes through routers. Any user with permission to create a Route CR object can bypass egress firewall policy rules by creating a route that points to a forbidden destination.

13.3.1.1. Limitations of an egress firewall

An egress firewall has the following limitations:

  • No project can have more than one EgressNetworkPolicy object.
  • The default project cannot use an egress firewall.
  • When using the OpenShift SDN default Container Network Interface (CNI) network provider in multitenant mode, the following limitations apply:

    • Global projects cannot use an egress firewall. You can make a project global by using the oc adm pod-network make-projects-global command.
    • Projects merged by using the oc adm pod-network join-projects command cannot use an egress firewall in any of the joined projects.

Violating any of these restrictions results in a broken egress firewall for the project, and may cause all external network traffic to be dropped.

13.3.1.2. Matching order for egress firewall policy rules

The egress firewall policy rules are evaluated in the order that they are defined, from first to last. The first rule that matches an egress connection from a pod applies. Any subsequent rules are ignored for that connection.

13.3.1.3. How Domain Name Server (DNS) resolution works

If you use DNS names in any of your egress firewall policy rules, proper resolution of the domain names is subject to the following restrictions:

  • Domain name updates are polled based on the TTL (time to live) value of the domain returned by the local non-authoritative servers.
  • The pod must resolve the domain from the same local name servers when necessary. Otherwise the IP addresses for the domain known by the egress firewall controller and the pod can be different. If the IP addresses for a hostname differ, the egress firewall might not be enforced consistently.
  • Because the egress firewall controller and pods asynchronously poll the same local name server, the pod might obtain the updated IP address before the egress controller does, which causes a race condition. Due to this current limitation, domain name usage in EgressNetworkPolicy objects is only recommended for domains with infrequent IP address changes.
Note

The egress firewall always allows pods access to the external interface of the node that the pod is on for DNS resolution.

If you use domain names in your egress firewall policy and your DNS resolution is not handled by a DNS server on the local node, then you must add egress firewall rules that allow access to your DNS server’s IP addresses. if you are using domain names in your pods.

13.3.2. EgressNetworkPolicy custom resource (CR) object

You can define one or more rules for an egress firewall. A rule is either an Allow rule or a Deny rule, with a specification for the traffic that the rule applies to.

The following YAML describes an EgressNetworkPolicy CR object:

EgressNetworkPolicy object

apiVersion: network.openshift.io/v1
kind: EgressNetworkPolicy
metadata:
  name: <name> 1
spec:
  egress: 2
    ...

1
A name for your egress firewall policy.
2
A collection of one or more egress network policy rules as described in the following section.

13.3.2.1. EgressNetworkPolicy rules

The following YAML describes an egress firewall rule object. The egress stanza expects an array of one or more objects.

Egress policy rule stanza

egress:
- type: <type> 1
  to: 2
    cidrSelector: <cidr> 3
    dnsName: <dns_name> 4

1
The type of rule. The value must be either Allow or Deny.
2
A stanza describing an egress traffic match rule. A value for either the cidrSelector field or the dnsName field for the rule. You cannot use both fields in the same rule.
3
An IP address range in CIDR format.
4
A domain name.

13.3.2.2. Example EgressNetworkPolicy CR objects

The following example defines several egress firewall policy rules:

apiVersion: network.openshift.io/v1
kind: EgressNetworkPolicy
metadata:
  name: default
spec:
  egress: 1
  - type: Allow
    to:
      cidrSelector: 1.2.3.0/24
  - type: Allow
    to:
      dnsName: www.example.com
  - type: Deny
    to:
      cidrSelector: 0.0.0.0/0
1
A collection of egress firewall policy rule objects.

13.3.3. Creating an egress firewall policy object

As a cluster administrator, you can create an egress firewall policy object for a project.

Important

If the project already has an EgressNetworkPolicy object defined, you must edit the existing policy to make changes to the egress firewall rules.

Prerequisites

  • A cluster that uses the OpenShift SDN default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift CLI (oc).
  • You must log in to the cluster as a cluster administrator.

Procedure

  1. Create a policy rule:

    1. Create a <policy_name>.yaml file where <policy_name> describes the egress policy rules.
    2. In the file you created, define an egress policy object.
  2. Enter the following command to create the policy object. Replace <policy_name> with the name of the policy and <project> with the project that the rule applies to.

    $ oc create -f <policy_name>.yaml -n <project>

    In the following example, a new EgressNetworkPolicy object is created in a project named project1:

    $ oc create -f default.yaml -n project1

    Example output

    egressnetworkpolicy.network.openshift.io/v1 created

  3. Optional: Save the <policy_name>.yaml file so that you can make changes later.

13.4. Editing an egress firewall for a project

As a cluster administrator, you can modify network traffic rules for an existing egress firewall.

13.4.1. Viewing an EgressNetworkPolicy object

You can view an EgressNetworkPolicy object in your cluster.

Prerequisites

  • A cluster using the OpenShift SDN default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift Command-line Interface (CLI), commonly known as oc.
  • You must log in to the cluster.

Procedure

  1. Optional: To view the names of the EgressNetworkPolicy objects defined in your cluster, enter the following command:

    $ oc get egressnetworkpolicy --all-namespaces
  2. To inspect a policy, enter the following command. Replace <policy_name> with the name of the policy to inspect.

    $ oc describe egressnetworkpolicy <policy_name>

    Example output

    Name:		default
    Namespace:	project1
    Created:	20 minutes ago
    Labels:		<none>
    Annotations:	<none>
    Rule:		Allow to 1.2.3.0/24
    Rule:		Allow to www.example.com
    Rule:		Deny to 0.0.0.0/0

13.5. Editing an egress firewall for a project

As a cluster administrator, you can modify network traffic rules for an existing egress firewall.

13.5.1. Editing an EgressNetworkPolicy object

As a cluster administrator, you can update the egress firewall for a project.

Prerequisites

  • A cluster using the OpenShift SDN default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift CLI (oc).
  • You must log in to the cluster as a cluster administrator.

Procedure

  1. Find the name of the EgressNetworkPolicy object for the project. Replace <project> with the name of the project.

    $ oc get -n <project> egressnetworkpolicy
  2. Optional: If you did not save a copy of the EgressNetworkPolicy object when you created the egress network firewall, enter the following command to create a copy.

    $ oc get -n <project> egressnetworkpolicy <name> -o yaml > <filename>.yaml

    Replace <project> with the name of the project. Replace <name> with the name of the object. Replace <filename> with the name of the file to save the YAML to.

  3. After making changes to the policy rules, enter the following command to replace the EgressNetworkPolicy object. Replace <filename> with the name of the file containing the updated EgressNetworkPolicy object.

    $ oc replace -f <filename>.yaml

13.6. Removing an egress firewall from a project

As a cluster administrator, you can remove an egress firewall from a project to remove all restrictions on network traffic from the project that leaves the OpenShift Container Platform cluster.

13.6.1. Removing an EgressNetworkPolicy object

As a cluster administrator, you can remove an egress firewall from a project.

Prerequisites

  • A cluster using the OpenShift SDN default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift CLI (oc).
  • You must log in to the cluster as a cluster administrator.

Procedure

  1. Find the name of the EgressNetworkPolicy object for the project. Replace <project> with the name of the project.

    $ oc get -n <project> egressnetworkpolicy
  2. Enter the following command to delete the EgressNetworkPolicy object. Replace <project> with the name of the project and <name> with the name of the object.

    $ oc delete -n <project> egressnetworkpolicy <name>

13.7. Considerations for the use of an egress router pod

13.7.1. About an egress router pod

The OpenShift Container Platform egress router pod redirects traffic to a specified remote server, using a private source IP address that is not used for any other purpose. This allows you to send network traffic to servers that are set up to allow access only from specific IP addresses.

Note

The egress router pod is not intended for every outgoing connection. Creating large numbers of egress router pods can exceed the limits of your network hardware. For example, creating an egress router pod for every project or application could exceed the number of local MAC addresses that the network interface can handle before reverting to filtering MAC addresses in software.

Important

The egress router image is not compatible with Amazon AWS, Azure Cloud, or any other cloud platform that does not support layer 2 manipulations due to their incompatibility with macvlan traffic.

13.7.1.1. Egress router modes

In redirect mode, an egress router pod sets up iptables rules to redirect traffic from its own IP address to one or more destination IP addresses. Client pods that need to use the reserved source IP address must be modified to connect to the egress router rather than connecting directly to the destination IP.

In HTTP proxy mode, an egress router pod runs as an HTTP proxy on port 8080. This mode only works for clients that are connecting to HTTP-based or HTTPS-based services, but usually requires fewer changes to the client pods to get them to work. Many programs can be told to use an HTTP proxy by setting an environment variable.

In DNS proxy mode, an egress router pod runs as a DNS proxy for TCP-based services from its own IP address to one or more destination IP addresses. To make use of the reserved, source IP address, client pods must be modified to connect to the egress router pod rather than connecting directly to the destination IP address. This modification ensures that external destinations treat traffic as though it were coming from a known source.

Redirect mode works for all services except for HTTP and HTTPS. For HTTP and HTTPS services, use HTTP proxy mode. For TCP-based services with IP addresses or domain names, use DNS proxy mode.

13.7.1.2. Egress router pod implementation

The egress router pod setup is performed by an initialization container. That container runs in a privileged context so that it can configure the macvlan interface and set up iptables rules. After the initialization container finishes setting up the iptables rules, it exits. Next the egress router pod executes the container to handle the egress router traffic. The image used varies depending on the egress router mode.

The environment variables determine which addresses the egress-router image uses. The image configures the macvlan interface to use EGRESS_SOURCE as its IP address, with EGRESS_GATEWAY as the IP address for the gateway.

Network Address Translation (NAT) rules are set up so that connections to the cluster IP address of the pod on any TCP or UDP port are redirected to the same port on IP address specified by the EGRESS_DESTINATION variable.

If only some of the nodes in your cluster are capable of claiming the specified source IP address and using the specified gateway, you can specify a nodeName or nodeSelector indicating which nodes are acceptable.

13.7.1.3. Deployment considerations

An egress router pod adds an additional IP address and MAC address to the primary network interface of the node. As a result, you might need to configure your hypervisor or cloud provider to allow the additional address.

Red Hat OpenStack Platform (RHOSP)

If you are deploying OpenShift Container Platform on RHOSP, you must whitelist the IP and MAC addresses on your OpenStack environment, otherwise communication will fail:

$ openstack port set --allowed-address \
  ip_address=<ip_address>,mac_address=<mac_address> <neutron_port_uuid>
Red Hat Virtualization (RHV)
If you are using RHV, you must select No Network Filter for the Virtual network interface controller (vNIC).
VMware vSphere
If you are using VMware vSphere, see the VMware documentation for securing vSphere standard switches. View and change VMware vSphere default settings by selecting the host virtual switch from the vSphere Web Client.

Specifically, ensure that the following are enabled:

13.7.1.4. Failover configuration

To avoid downtime, you can deploy an egress router pod with a Deployment resource, as in the following example. To create a new Service object for the example deployment, use the oc expose deployment/egress-demo-controller command.

apiVersion: v1
kind: Deployment
metadata:
  name: egress-demo-controller
spec:
  replicas: 1 1
  selector:
    name: egress-router
  template:
    metadata:
      name: egress-router
      labels:
        name: egress-router
      annotations:
        pod.network.openshift.io/assign-macvlan: "true"
    spec: 2
      initContainers:
        ...
      containers:
        ...
1
Ensure that replicas is set to 1, because only one pod can use a given egress source IP address at any time. This means that only a single copy of the router runs on a node.
2
Specify the Pod object template for the egress router pod.

13.7.2. Additional resources

13.8. Deploying an egress router pod in redirect mode

As a cluster administrator, you can deploy an egress router pod that is configured to redirect traffic to specified destination IP addresses.

13.8.1. Egress router pod specification for redirect mode

Define the configuration for an egress router pod in the Pod object. The following YAML describes the fields for the configuration of an egress router pod in redirect mode:

apiVersion: v1
kind: Pod
metadata:
  name: egress-1
  labels:
    name: egress-1
  annotations:
    pod.network.openshift.io/assign-macvlan: "true" 1
spec:
  initContainers:
  - name: egress-router
    image: registry.redhat.io/openshift4/ose-egress-router
    securityContext:
      privileged: true
    env:
    - name: EGRESS_SOURCE 2
      value: <egress_router>
    - name: EGRESS_GATEWAY 3
      value: <egress_gateway>
    - name: EGRESS_DESTINATION 4
      value: <egress_destination>
    - name: EGRESS_ROUTER_MODE
      value: init
  containers:
  - name: egress-router-wait
    image: registry.redhat.io/openshift4/ose-pod
1
The annotation tells OpenShift Container Platform to create a macvlan network interface on the primary network interface controller (NIC) and move that macvlan interface into the pod’s network namespace. You must include the quotation marks around the "true" value. To have OpenShift Container Platform create the macvlan interface on a different NIC interface, set the annotation value to the name of that interface. For example, eth1.
2
IP address from the physical network that the node is on that is reserved for use by the egress router pod. Optional: You can include the subnet length, the /24 suffix, so that a proper route to the local subnet is set. If you do not specify a subnet length, then the egress router can access only the host specified with the EGRESS_GATEWAY variable and no other hosts on the subnet.
3
Same value as the default gateway used by the node.
4
External server to direct traffic to. Using this example, connections to the pod are redirected to 203.0.113.25, with a source IP address of 192.168.12.99.

Example egress router pod specification

apiVersion: v1
kind: Pod
metadata:
  name: egress-multi
  labels:
    name: egress-multi
  annotations:
    pod.network.openshift.io/assign-macvlan: "true"
spec:
  initContainers:
  - name: egress-router
    image: registry.redhat.io/openshift4/ose-egress-router
    securityContext:
      privileged: true
    env:
    - name: EGRESS_SOURCE
      value: 192.168.12.99/24
    - name: EGRESS_GATEWAY
      value: 192.168.12.1
    - name: EGRESS_DESTINATION
      value: |
        80   tcp 203.0.113.25
        8080 tcp 203.0.113.26 80
        8443 tcp 203.0.113.26 443
        203.0.113.27
    - name: EGRESS_ROUTER_MODE
      value: init
  containers:
  - name: egress-router-wait
    image: registry.redhat.io/openshift4/ose-pod

13.8.2. Egress destination configuration format

When an egress router pod is deployed in redirect mode, you can specify redirection rules by using one or more of the following formats:

  • <port> <protocol> <ip_address> - Incoming connections to the given <port> should be redirected to the same port on the given <ip_address>. <protocol> is either tcp or udp.
  • <port> <protocol> <ip_address> <remote_port> - As above, except that the connection is redirected to a different <remote_port> on <ip_address>.
  • <ip_address> - If the last line is a single IP address, then any connections on any other port will be redirected to the corresponding port on that IP address. If there is no fallback IP address then connections on other ports are rejected.

In the example that follows several rules are defined:

  • The first line redirects traffic from local port 80 to port 80 on 203.0.113.25.
  • The second and third lines redirect local ports 8080 and 8443 to remote ports 80 and 443 on 203.0.113.26.
  • The last line matches traffic for any ports not specified in the previous rules.

Example configuration

80   tcp 203.0.113.25
8080 tcp 203.0.113.26 80
8443 tcp 203.0.113.26 443
203.0.113.27

13.8.3. Deploying an egress router pod in redirect mode

In redirect mode, an egress router pod sets up iptables rules to redirect traffic from its own IP address to one or more destination IP addresses. Client pods that need to use the reserved source IP address must be modified to connect to the egress router rather than connecting directly to the destination IP.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create an egress router pod.
  2. To ensure that other pods can find the IP address of the egress router pod, create a service to point to the egress router pod, as in the following example:

    apiVersion: v1
    kind: Service
    metadata:
      name: egress-1
    spec:
      ports:
      - name: http
        port: 80
      - name: https
        port: 443
      type: ClusterIP
      selector:
        name: egress-1

    Your pods can now connect to this service. Their connections are redirected to the corresponding ports on the external server, using the reserved egress IP address.

13.8.4. Additional resources

13.9. Deploying an egress router pod in HTTP proxy mode

As a cluster administrator, you can deploy an egress router pod configured to proxy traffic to specified HTTP and HTTPS-based services.

13.9.1. Egress router pod specification for HTTP mode

Define the configuration for an egress router pod in the Pod object. The following YAML describes the fields for the configuration of an egress router pod in HTTP mode:

apiVersion: v1
kind: Pod
metadata:
  name: egress-1
  labels:
    name: egress-1
  annotations:
    pod.network.openshift.io/assign-macvlan: "true" 1
spec:
  initContainers:
  - name: egress-router
    image: registry.redhat.io/openshift4/ose-egress-router
    securityContext:
      privileged: true
    env:
    - name: EGRESS_SOURCE 2
      value: <egress-router>
    - name: EGRESS_GATEWAY 3
      value: <egress-gateway>
    - name: EGRESS_ROUTER_MODE
      value: http-proxy
  containers:
  - name: egress-router-pod
    image: registry.redhat.io/openshift4/ose-egress-http-proxy
    env:
    - name: EGRESS_HTTP_PROXY_DESTINATION 4
      value: |-
        ...
    ...
1
The annotation tells OpenShift Container Platform to create a macvlan network interface on the primary network interface controller (NIC) and move that macvlan interface into the pod’s network namespace. You must include the quotation marks around the "true" value. To have OpenShift Container Platform create the macvlan interface on a different NIC interface, set the annotation value to the name of that interface. For example, eth1.
2
IP address from the physical network that the node is on that is reserved for use by the egress router pod. Optional: You can include the subnet length, the /24 suffix, so that a proper route to the local subnet is set. If you do not specify a subnet length, then the egress router can access only the host specified with the EGRESS_GATEWAY variable and no other hosts on the subnet.
3
Same value as the default gateway used by the node.
4
A string or YAML multi-line string specifying how to configure the proxy. Note that this is specified as an environment variable in the HTTP proxy container, not with the other environment variables in the init container.

13.9.2. Egress destination configuration format

When an egress router pod is deployed in HTTP proxy mode, you can specify redirection rules by using one or more of the following formats. Each line in the configuration specifies one group of connections to allow or deny:

  • An IP address allows connections to that IP address, such as 192.168.1.1.
  • A CIDR range allows connections to that CIDR range, such as 192.168.1.0/24.
  • A hostname allows proxying to that host, such as www.example.com.
  • A domain name preceded by *. allows proxying to that domain and all of its subdomains, such as *.example.com.
  • A ! followed by any of the previous match expressions denies the connection instead.
  • If the last line is *, then anything that is not explicitly denied is allowed. Otherwise, anything that is not allowed is denied.

You can also use * to allow connections to all remote destinations.

Example configuration

!*.example.com
!192.168.1.0/24
192.168.2.1
*

13.9.3. Deploying an egress router pod in HTTP proxy mode

In HTTP proxy mode, an egress router pod runs as an HTTP proxy on port 8080. This mode only works for clients that are connecting to HTTP-based or HTTPS-based services, but usually requires fewer changes to the client pods to get them to work. Many programs can be told to use an HTTP proxy by setting an environment variable.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create an egress router pod.
  2. To ensure that other pods can find the IP address of the egress router pod, create a service to point to the egress router pod, as in the following example:

    apiVersion: v1
    kind: Service
    metadata:
      name: egress-1
    spec:
      ports:
      - name: http-proxy
        port: 8080 1
      type: ClusterIP
      selector:
        name: egress-1
    1
    Ensure the http port is set to 8080.
  3. To configure the client pod (not the egress proxy pod) to use the HTTP proxy, set the http_proxy or https_proxy variables:

    apiVersion: v1
    kind: Pod
    metadata:
      name: app-1
      labels:
        name: app-1
    spec:
      containers:
        env:
        - name: http_proxy
          value: http://egress-1:8080/ 1
        - name: https_proxy
          value: http://egress-1:8080/
        ...
    1
    The service created in the previous step.
    Note

    Using the http_proxy and https_proxy environment variables is not necessary for all setups. If the above does not create a working setup, then consult the documentation for the tool or software you are running in the pod.

13.9.4. Additional resources

13.10. Deploying an egress router pod in DNS proxy mode

As a cluster administrator, you can deploy an egress router pod configured to proxy traffic to specified DNS names and IP addresses.

13.10.1. Egress router pod specification for DNS mode

Define the configuration for an egress router pod in the Pod object. The following YAML describes the fields for the configuration of an egress router pod in DNS mode:

apiVersion: v1
kind: Pod
metadata:
  name: egress-1
  labels:
    name: egress-1
  annotations:
    pod.network.openshift.io/assign-macvlan: "true" 1
spec:
  initContainers:
  - name: egress-router
    image: registry.redhat.io/openshift4/ose-egress-router
    securityContext:
      privileged: true
    env:
    - name: EGRESS_SOURCE 2
      value: <egress-router>
    - name: EGRESS_GATEWAY 3
      value: <egress-gateway>
    - name: EGRESS_ROUTER_MODE
      value: dns-proxy
  containers:
  - name: egress-router-pod
    image: registry.redhat.io/openshift4/ose-egress-dns-proxy
    securityContext:
      privileged: true
    env:
    - name: EGRESS_DNS_PROXY_DESTINATION 4
      value: |-
        ...
    - name: EGRESS_DNS_PROXY_DEBUG 5
      value: "1"
    ...
1
The annotation tells OpenShift Container Platform to create a macvlan network interface on the primary network interface controller (NIC) and move that macvlan interface into the pod’s network namespace. You must include the quotation marks around the "true" value. To have OpenShift Container Platform create the macvlan interface on a different NIC interface, set the annotation value to the name of that interface. For example, eth1.
2
IP address from the physical network that the node is on that is reserved for use by the egress router pod. Optional: You can include the subnet length, the /24 suffix, so that a proper route to the local subnet is set. If you do not specify a subnet length, then the egress router can access only the host specified with the EGRESS_GATEWAY variable and no other hosts on the subnet.
3
Same value as the default gateway used by the node.
4
Specify a list of one or more proxy destinations.
5
Optional: Specify to output the DNS proxy log output to stdout.

13.10.2. Egress destination configuration format

When the router is deployed in DNS proxy mode, you specify a list of port and destination mappings. A destination may be either an IP address or a DNS name.

An egress router pod supports the following formats for specifying port and destination mappings:

Port and remote address
You can specify a source port and a destination host by using the two field format: <port> <remote_address>.

The host can be an IP address or a DNS name. If a DNS name is provided, DNS resolution occurs at runtime. For a given host, the proxy connects to the specified source port on the destination host when connecting to the destination host IP address.

Port and remote address pair example

80 172.16.12.11
100 example.com

Port, remote address, and remote port
You can specify a source port, a destination host, and a destination port by using the three field format: <port> <remote_address> <remote_port>.

The three field format behaves identically to the two field version, with the exception that the destination port can be different than the source port.

Port, remote address, and remote port example

8080 192.168.60.252 80
8443 web.example.com 443

13.10.3. Deploying an egress router pod in DNS proxy mode

In DNS proxy mode, an egress router pod acts as a DNS proxy for TCP-based services from its own IP address to one or more destination IP addresses.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create an egress router pod.
  2. Create a service for the egress router pod:

    1. Create a file named egress-router-service.yaml that contains the following YAML. Set spec.ports to the list of ports that you defined previously for the EGRESS_DNS_PROXY_DESTINATION environment variable.

      apiVersion: v1
      kind: Service
      metadata:
        name: egress-dns-svc
      spec:
        ports:
          ...
        type: ClusterIP
        selector:
          name: egress-dns-proxy

      For example:

      apiVersion: v1
      kind: Service
      metadata:
        name: egress-dns-svc
      spec:
        ports:
        - name: con1
          protocol: TCP
          port: 80
          targetPort: 80
        - name: con2
          protocol: TCP
          port: 100
          targetPort: 100
        type: ClusterIP
        selector:
          name: egress-dns-proxy
    2. To create the service, enter the following command:

      $ oc create -f egress-router-service.yaml

      Pods can now connect to this service. The connections are proxied to the corresponding ports on the external server, using the reserved egress IP address.

13.10.4. Additional resources

13.11. Configuring an egress router pod destination list from a config map

As a cluster administrator, you can define a ConfigMap object that specifies destination mappings for an egress router pod. The specific format of the configuration depends on the type of egress router pod. For details on the format, refer to the documentation for the specific egress router pod.

13.11.1. Configuring an egress router destination mappings with a config map

For a large or frequently-changing set of destination mappings, you can use a config map to externally maintain the list. An advantage of this approach is that permission to edit the config map can be delegated to users without cluster-admin privileges. Because the egress router pod requires a privileged container, it is not possible for users without cluster-admin privileges to edit the pod definition directly.

Note

The egress router pod does not automatically update when the config map changes. You must restart the egress router pod to get updates.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create a file containing the mapping data for the egress router pod, as in the following example:

    # Egress routes for Project "Test", version 3
    
    80   tcp 203.0.113.25
    
    8080 tcp 203.0.113.26 80
    8443 tcp 203.0.113.26 443
    
    # Fallback
    203.0.113.27

    You can put blank lines and comments into this file.

  2. Create a ConfigMap object from the file:

    $ oc delete configmap egress-routes --ignore-not-found
    $ oc create configmap egress-routes \
      --from-file=destination=my-egress-destination.txt

    In the previous command, the egress-routes value is the name of the ConfigMap object to create and my-egress-destination.txt is the name of the file that the data is read from.

  3. Create an egress router pod definition and specify the configMapKeyRef stanza for the EGRESS_DESTINATION field in the environment stanza:

    ...
    env:
    - name: EGRESS_DESTINATION
      valueFrom:
        configMapKeyRef:
          name: egress-routes
          key: destination
    ...

13.11.2. Additional resources

13.12. Enabling multicast for a project

13.12.1. About multicast

With IP multicast, data is broadcast to many IP addresses simultaneously.

Important

At this time, multicast is best used for low-bandwidth coordination or service discovery and not a high-bandwidth solution.

Multicast traffic between OpenShift Container Platform pods is disabled by default. If you are using the OpenShift SDN default Container Network Interface (CNI) network provider, you can enable multicast on a per-project basis.

When using the OpenShift SDN network plug-in in networkpolicy isolation mode:

  • Multicast packets sent by a pod will be delivered to all other pods in the project, regardless of NetworkPolicy objects. Pods might be able to communicate over multicast even when they cannot communicate over unicast.
  • Multicast packets sent by a pod in one project will never be delivered to pods in any other project, even if there are NetworkPolicy objects that allow communication between the projects.

When using the OpenShift SDN network plug-in in multitenant isolation mode:

  • Multicast packets sent by a pod will be delivered to all other pods in the project.
  • Multicast packets sent by a pod in one project will be delivered to pods in other projects only if each project is joined together and multicast is enabled in each joined project.

13.12.2. Enabling multicast between pods

You can enable multicast between pods for your project.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  • Run the following command to enable multicast for a project. Replace <namespace> with the namespace for the project you want to enable multicast for.

    $ oc annotate netnamespace <namespace> \
        netnamespace.network.openshift.io/multicast-enabled=true

Verification

To verify that multicast is enabled for a project, complete the following procedure:

  1. Change your current project to the project that you enabled multicast for. Replace <project> with the project name.

    $ oc project <project>
  2. Create a pod to act as a multicast receiver:

    $ cat <<EOF| oc create -f -
    apiVersion: v1
    kind: Pod
    metadata:
      name: mlistener
      labels:
        app: multicast-verify
    spec:
      containers:
        - name: mlistener
          image: registry.access.redhat.com/ubi8
          command: ["/bin/sh", "-c"]
          args:
            ["dnf -y install socat hostname && sleep inf"]
          ports:
            - containerPort: 30102
              name: mlistener
              protocol: UDP
    EOF
  3. Create a pod to act as a multicast sender:

    $ cat <<EOF| oc create -f -
    apiVersion: v1
    kind: Pod
    metadata:
      name: msender
      labels:
        app: multicast-verify
    spec:
      containers:
        - name: msender
          image: registry.access.redhat.com/ubi8
          command: ["/bin/sh", "-c"]
          args:
            ["dnf -y install socat && sleep inf"]
    EOF
  4. In a new terminal window or tab, start the multicast listener.

    1. Get the IP address for the Pod:

      $ POD_IP=$(oc get pods mlistener -o jsonpath='{.status.podIP}')
    2. Start the multicast listener by entering the following command:

      $ oc exec mlistener -i -t -- \
          socat UDP4-RECVFROM:30102,ip-add-membership=224.1.0.1:$POD_IP,fork EXEC:hostname
  5. Start the multicast transmitter.

    1. Get the pod network IP address range:

      $ CIDR=$(oc get Network.config.openshift.io cluster \
          -o jsonpath='{.status.clusterNetwork[0].cidr}')
    2. To send a multicast message, enter the following command:

      $ oc exec msender -i -t -- \
          /bin/bash -c "echo | socat STDIO UDP4-DATAGRAM:224.1.0.1:30102,range=$CIDR,ip-multicast-ttl=64"

      If multicast is working, the previous command returns the following output:

      mlistener

13.13. Disabling multicast for a project

13.13.1. Disabling multicast between pods

You can disable multicast between pods for your project.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  • Disable multicast by running the following command:

    $ oc annotate netnamespace <namespace> \ 1
        netnamespace.network.openshift.io/multicast-enabled-
    1
    The namespace for the project you want to disable multicast for.

13.14. Configuring network isolation using OpenShift SDN

When your cluster is configured to use the multitenant isolation mode for the OpenShift SDN CNI plug-in, each project is isolated by default. Network traffic is not allowed between pods or services in different projects in multitenant isolation mode.

You can change the behavior of multitenant isolation for a project in two ways:

  • You can join one or more projects, allowing network traffic between pods and services in different projects.
  • You can disable network isolation for a project. It will be globally accessible, accepting network traffic from pods and services in all other projects. A globally accessible project can access pods and services in all other projects.

13.14.1. Prerequisites

  • You must have a cluster configured to use the OpenShift SDN Container Network Interface (CNI) plug-in in multitenant isolation mode.

13.14.2. Joining projects

You can join two or more projects to allow network traffic between pods and services in different projects.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  1. Use the following command to join projects to an existing project network:

    $ oc adm pod-network join-projects --to=<project1> <project2> <project3>

    Alternatively, instead of specifying specific project names, you can use the --selector=<project_selector> option to specify projects based upon an associated label.

  2. Optional: Run the following command to view the pod networks that you have joined together:

    $ oc get netnamespaces

    Projects in the same pod-network have the same network ID in the NETID column.

13.14.3. Isolating a project

You can isolate a project so that pods and services in other projects cannot access its pods and services.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  • To isolate the projects in the cluster, run the following command:

    $ oc adm pod-network isolate-projects <project1> <project2>

    Alternatively, instead of specifying specific project names, you can use the --selector=<project_selector> option to specify projects based upon an associated label.

13.14.4. Disabling network isolation for a project

You can disable network isolation for a project.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  • Run the following command for the project:

    $ oc adm pod-network make-projects-global <project1> <project2>

    Alternatively, instead of specifying specific project names, you can use the --selector=<project_selector> option to specify projects based upon an associated label.

13.15. Configuring kube-proxy

The Kubernetes network proxy (kube-proxy) runs on each node and is managed by the Cluster Network Operator (CNO). kube-proxy maintains network rules for forwarding connections for endpoints associated with services.

13.15.1. About iptables rules synchronization

The synchronization period determines how frequently the Kubernetes network proxy (kube-proxy) syncs the iptables rules on a node.

A sync begins when either of the following events occurs:

  • An event occurs, such as service or endpoint is added to or removed from the cluster.
  • The time since the last sync exceeds the sync period defined for kube-proxy.

13.15.2. kube-proxy configuration parameters

You can modify the following kubeProxyConfig parameters.

Note

Because of performance improvements introduced in OpenShift Container Platform 4.3 and greater, adjusting the iptablesSyncPeriod parameter is no longer necessary.

Table 13.2. Parameters

ParameterDescriptionValuesDefault

iptablesSyncPeriod

The refresh period for iptables rules.

A time interval, such as 30s or 2m. Valid suffixes include s, m, and h and are described in the Go time package documentation.

30s

proxyArguments.iptables-min-sync-period

The minimum duration before refreshing iptables rules. This parameter ensures that the refresh does not happen too frequently. By default, a refresh starts as soon as a change that affects iptables rules occurs.

A time interval, such as 30s or 2m. Valid suffixes include s, m, and h and are described in the Go time package

0s

13.15.3. Modifying the kube-proxy configuration

You can modify the Kubernetes network proxy configuration for your cluster.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in to a running cluster with the cluster-admin role.

Procedure

  1. Edit the Network.operator.openshift.io custom resource (CR) by running the following command:

    $ oc edit network.operator.openshift.io cluster
  2. Modify the kubeProxyConfig parameter in the CR with your changes to the kube-proxy configuration, such as in the following example CR:

    apiVersion: operator.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      kubeProxyConfig:
        iptablesSyncPeriod: 30s
        proxyArguments:
          iptables-min-sync-period: ["30s"]
  3. Save the file and exit the text editor.

    The syntax is validated by the oc command when you save the file and exit the editor. If your modifications contain a syntax error, the editor opens the file and displays an error message.

  4. Enter the following command to confirm the configuration update:

    $ oc get networks.operator.openshift.io -o yaml

    Example output

    apiVersion: v1
    items:
    - apiVersion: operator.openshift.io/v1
      kind: Network
      metadata:
        name: cluster
      spec:
        clusterNetwork:
        - cidr: 10.128.0.0/14
          hostPrefix: 23
        defaultNetwork:
          type: OpenShiftSDN
        kubeProxyConfig:
          iptablesSyncPeriod: 30s
          proxyArguments:
            iptables-min-sync-period:
            - 30s
        serviceNetwork:
        - 172.30.0.0/16
      status: {}
    kind: List

  5. Optional: Enter the following command to confirm that the Cluster Network Operator accepted the configuration change:

    $ oc get clusteroperator network

    Example output

    NAME      VERSION     AVAILABLE   PROGRESSING   DEGRADED   SINCE
    network   4.1.0-0.9   True        False         False      1m

    The AVAILABLE field is True when the configuration update is applied successfully.

Chapter 14. OVN-Kubernetes default CNI network provider

14.1. About the OVN-Kubernetes default Container Network Interface (CNI) network provider

The OpenShift Container Platform cluster uses a virtualized network for pod and service networks. The OVN-Kubernetes Container Network Interface (CNI) plug-in is a network provider for the default cluster network. OVN-Kubernetes is based on Open Virtual Network (OVN) and provides an overlay-based networking implementation. A cluster that uses the OVN-Kubernetes network provider also runs Open vSwitch (OVS) on each node. OVN configures OVS on each node to implement the declared network configuration.

14.1.1. OVN-Kubernetes features

The OVN-Kubernetes Container Network Interface (CNI) cluster network provider implements the following features:

  • Uses OVN (Open Virtual Network) to manage network traffic flows. OVN is a community developed, vendor-agnostic network virtualization solution.
  • Implements Kubernetes network policy support, including ingress and egress rules.
  • Uses the Geneve (Generic Network Virtualization Encapsulation) protocol rather than VXLAN to create an overlay network between nodes.

14.1.2. Supported default CNI network provider feature matrix

OpenShift Container Platform offers two supported choices, OpenShift SDN and OVN-Kubernetes, for the default Container Network Interface (CNI) network provider. The following table summarizes the current feature support for both network providers:

Table 14.1. Default CNI network provider feature comparison

FeatureOVN-KubernetesOpenShift SDN

Egress IPs

Supported

Supported

Egress firewall [1]

Supported

Supported

Egress router

Not supported

Supported

Kubernetes network policy

Supported

Partially supported [2]

Multicast

Supported

Supported

  1. Egress firewall is also known as egress network policy in OpenShift SDN. This is not the same as network policy egress.
  2. Does not support egress rules and some ipBlock rules.

14.1.3. OVN-Kubernetes limitations

The OVN-Kubernetes Container Network Interface (CNI) cluster network provider has a limitation that is related to traffic policies. The network provider does not support setting the external traffic policy or internal traffic policy for a Kubernetes service to local. The default value, cluster, is supported for both parameters. This limitation can affect you when you add a service of type LoadBalancer, NodePort, or add a service with an external IP.

14.2. Migrating from the OpenShift SDN cluster network provider

As a cluster administrator, you can migrate to the OVN-Kubernetes Container Network Interface (CNI) cluster network provider from the OpenShift SDN CNI cluster network provider.

To learn more about OVN-Kubernetes, read About the OVN-Kubernetes network provider.

14.2.1. Migration to the OVN-Kubernetes network provider

Migrating to the OVN-Kubernetes Container Network Interface (CNI) default network provider is a manual process that includes some downtime during which your cluster is unreachable. Although a rollback procedure is provided, the migration is intended to be a one-way process.

Note

A migration to the OVN-Kubernetes network provider is supported on installer-provisioned clusters on only bare metal hardware.

Performing a migration on a user-provisioned cluster on bare metal hardware is not supported.

14.2.1.1. Considerations for migrating to the OVN-Kubernetes network provider

The subnets assigned to nodes and the IP addresses assigned to individual pods are not preserved during the migration.

While the OVN-Kubernetes network provider implements many of the capabilities present in the OpenShift SDN network provider, the configuration is not the same.

  • If your cluster uses any of the following OpenShift SDN capabilities, you must manually configure the same capability in OVN-Kubernetes:

    • Namespace isolation
    • Egress IP addresses
    • Egress network policies
    • Egress router pods
    • Multicast
  • If your cluster uses any part of the 100.64.0.0/16 IP address range, you cannot migrate to OVN-Kubernetes because it uses this IP address range internally.

The following sections highlight the differences in configuration between the aforementioned capabilities in OVN-Kubernetes and OpenShift SDN.

Namespace isolation

OVN-Kubernetes supports only the network policy isolation mode.

Important

If your cluster uses OpenShift SDN configured in either the multitenant or subnet isolation modes, you cannot migrate to the OVN-Kubernetes network provider.

Egress IP addresses

The differences in configuring an egress IP address between OVN-Kubernetes and OpenShift SDN is described in the following table:

Table 14.2. Differences in egress IP address configuration

OVN-KubernetesOpenShift SDN
  • Create an EgressIPs object
  • Add an annotation on a Node object
  • Patch a NetNamespace object
  • Patch a HostSubnet object

For more information on using egress IP addresses in OVN-Kubernetes, see "Configuring an egress IP address".

Egress network policies

The difference in configuring an egress network policy, also known as an egress firewall, between OVN-Kubernetes and OpenShift SDN is described in the following table:

Table 14.3. Differences in egress network policy configuration

OVN-KubernetesOpenShift SDN
  • Create an EgressFirewall object in a namespace
  • Create an EgressNetworkPolicy object in a namespace

For more information on using an egress firewall in OVN-Kubernetes, see "Configuring an egress firewall for a project".

Egress router pods

OVN-Kubernetes does not support using egress router pods in OpenShift Container Platform 4.6.

Multicast

The difference between enabling multicast traffic on OVN-Kubernetes and OpenShift SDN is described in the following table:

Table 14.4. Differences in multicast configuration

OVN-KubernetesOpenShift SDN
  • Add an annotation on a Namespace object
  • Add an annotation on a NetNamespace object

For more information on using multicast in OVN-Kubernetes, see "Enabling multicast for a project".

Network policies

OVN-Kubernetes fully supports the Kubernetes NetworkPolicy API in the networking.k8s.io/v1 API group. No changes are necessary in your network policies when migrating from OpenShift SDN.

14.2.1.2. How the migration process works

The migration process works as follows:

  1. Set a temporary annotation set on the Cluster Network Operator (CNO) configuration object. This annotation triggers the CNO to watch for a change to the defaultNetwork field.
  2. Suspend the Machine Config Operator (MCO) to ensure that it does not interrupt the migration.
  3. Update the defaultNetwork field. The update causes the CNO to destroy the OpenShift SDN control plane pods and deploy the OVN-Kubernetes control plane pods. Additionally, it updates the Multus objects to reflect the new cluster network provider.
  4. Reboot each node in the cluster. Because the existing pods in the cluster are unaware of the change to the cluster network provider, rebooting each node ensures that each node is drained of pods. New pods are attached to the new cluster network provided by OVN-Kubernetes.
  5. Enable the MCO after all nodes in the cluster reboot. The MCO rolls out an update to the systemd configuration necessary to complete the migration. The MCO updates a single machine per pool at a time by default, so the total time the migration takes increases with the size of the cluster.

14.2.2. Migrating to the OVN-Kubernetes default CNI network provider

As a cluster administrator, you can change the default Container Network Interface (CNI) network provider for your cluster to OVN-Kubernetes. During the migration, you must reboot every node in your cluster.

Important

While performing the migration, your cluster is unavailable and workloads might be interrupted. Perform the migration only when an interruption in service is acceptable.

Prerequisites

  • A cluster installed on bare metal installer-provisioned infrastructure and configured with the OpenShift SDN default CNI network provider in the network policy isolation mode.
  • Install the OpenShift CLI (oc).
  • Access to the cluster as a user with the cluster-admin role.
  • A recent backup of the etcd database is available.
  • The cluster is in a known good state, without any errors.

Procedure

  1. To backup the configuration for the cluster network, enter the following command:

    $ oc get Network.config.openshift.io cluster -o yaml > cluster-openshift-sdn.yaml
  2. To enable the migration, set an annotation on the Cluster Network Operator configuration object by entering the following command:

    $ oc annotate Network.operator.openshift.io cluster \
      'networkoperator.openshift.io/network-migration'=""
  3. Stop all of the machine configuration pools managed by the Machine Config Operator (MCO):

    • Stop the master configuration pool:

      $ oc patch MachineConfigPool master --type='merge' --patch \
        '{ "spec": { "paused": true } }'
    • Stop the worker configuration pool:

      $ oc patch MachineConfigPool worker --type='merge' --patch \
        '{ "spec":{ "paused" :true } }'
  4. To configure the OVN-Kubernetes cluster network provider, enter the following command:

    $ oc patch Network.config.openshift.io cluster \
      --type='merge' --patch '{ "spec": { "networkType": "OVNKubernetes" } }'
  5. Optional: You can customize the following settings for OVN-Kubernetes to meet your network infrastructure requirements:

    • Maximum transmission unit (MTU)
    • Geneve (Generic Network Virtualization Encapsulation) overlay network port

    To customize either of the previously noted settings, enter and customize the following command. If you do not need to change the default value, omit the key from the patch.

    $ oc patch Network.operator.openshift.io cluster --type=merge \
      --patch '{
        "spec":{
          "defaultNetwork":{
            "ovnKubernetesConfig":{
              "mtu":<mtu>,
              "genevePort":<port>
        }}}}'
    mtu
    The MTU for the Geneve overlay network. This value is normally configured automatically, but if the nodes in your cluster do not all use the same MTU, then you must set this explicitly to 100 less than the smallest node MTU value.
    port
    The UDP port for the Geneve overlay network.

    Example patch command to update mtu field

    $ oc patch Network.operator.openshift.io cluster --type=merge \
      --patch '{
        "spec":{
          "defaultNetwork":{
            "ovnKubernetesConfig":{
              "mtu":1200
        }}}}'

  6. Wait until the Multus daemon set rollout completes.

    $ oc -n openshift-multus rollout status daemonset/multus

    The name of the Multus pods is in form of multus-<xxxxx> where <xxxxx> is a random sequence of letters. It might take several moments for the pods to restart.

    Example output

    Waiting for daemon set "multus" rollout to finish: 1 out of 6 new pods have been updated...
    ...
    Waiting for daemon set "multus" rollout to finish: 5 of 6 updated pods are available...
    daemon set "multus" successfully rolled out

  7. To complete the migration, reboot each node in your cluster. For example, you can use a bash script similar to the following example. The script assumes that you can connect to each host by using ssh and that you have configured sudo to not prompt for a password.

    #!/bin/bash
    
    for ip in $(oc get nodes  -o jsonpath='{.items[*].status.addresses[?(@.type=="InternalIP")].address}')
    do
       echo "reboot node $ip"
       ssh -o StrictHostKeyChecking=no core@$ip sudo shutdown -r -t 3
    done

    If ssh access is not available, you might be able to reboot each node through the management portal for your infrastructure provider.

  8. After the nodes in your cluster have rebooted, start all of the machine configuration pools:

    • Start the master configuration pool:

      $ oc patch MachineConfigPool master --type='merge' --patch \
        '{ "spec": { "paused": false } }'
    • Start the worker configuration pool:

      $ oc patch MachineConfigPool worker --type='merge' --patch \
        '{ "spec": { "paused": false } }'

    As the MCO updates machines in each config pool, it reboots each node.

    By default the MCO updates a single machine per pool at a time, so the time that the migration requires to complete grows with the size of the cluster.

  9. Confirm the status of the new machine configuration on the hosts:

    1. To list the machine configuration state and the name of the applied machine configuration, enter the following command:

      $ oc describe node | egrep "hostname|machineconfig"

      Example output

      kubernetes.io/hostname=master-0
      machineconfiguration.openshift.io/currentConfig: rendered-master-c53e221d9d24e1c8bb6ee89dd3d8ad7b
      machineconfiguration.openshift.io/desiredConfig: rendered-master-c53e221d9d24e1c8bb6ee89dd3d8ad7b
      machineconfiguration.openshift.io/reason:
      machineconfiguration.openshift.io/state: Done

      Verify that the following statements are true:

      • The value of machineconfiguration.openshift.io/state field is Done.
      • The value of the machineconfiguration.openshift.io/currentConfig field is equal to the value of the machineconfiguration.openshift.io/desiredConfig field.
    2. To confirm that the machine config is correct, enter the following command:

      $ oc get machineconfig <config_name> -o yaml | grep ExecStart

      where <config_name> is the name of the machine config from the machineconfiguration.openshift.io/currentConfig field.

      The machine config must include the following update to the systemd configuration:

      ExecStart=/usr/local/bin/configure-ovs.sh OVNKubernetes
  10. Confirm that the migration succeeded:

    1. To confirm that the default CNI network provider is OVN-Kubernetes, enter the following command. The value of status.networkType must be OVNKubernetes.

      $ oc get network.config/cluster -o jsonpath='{.status.networkType}{"\n"}'
    2. To confirm that the cluster nodes are in the Ready state, enter the following command:

      $ oc get nodes
    3. If a node is stuck in the NotReady state, investigate the machine config daemon pod logs and resolve any errors.

      1. To list the pods, enter the following command:

        $ oc get pod -n openshift-machine-config-operator

        Example output

        NAME                                         READY   STATUS    RESTARTS   AGE
        machine-config-controller-75f756f89d-sjp8b   1/1     Running   0          37m
        machine-config-daemon-5cf4b                  2/2     Running   0          43h
        machine-config-daemon-7wzcd                  2/2     Running   0          43h
        machine-config-daemon-fc946                  2/2     Running   0          43h
        machine-config-daemon-g2v28                  2/2     Running   0          43h
        machine-config-daemon-gcl4f                  2/2     Running   0          43h
        machine-config-daemon-l5tnv                  2/2     Running   0          43h
        machine-config-operator-79d9c55d5-hth92      1/1     Running   0          37m
        machine-config-server-bsc8h                  1/1     Running   0          43h
        machine-config-server-hklrm                  1/1     Running   0          43h
        machine-config-server-k9rtx                  1/1     Running   0          43h

        The names for the config daemon pods are in the following format: machine-config-daemon-<seq>. The <seq> value is a random five character alphanumeric sequence.

      2. Display the pod log for the first machine config daemon pod shown in the previous output by enter the following command:

        $ oc logs <pod> -n openshift-machine-config-operator

        where pod is the name of a machine config daemon pod.

      3. Resolve any errors in the logs shown by the output from the previous command.
    4. To confirm that your pods are not in an error state, enter the following command:

      $ oc get pods --all-namespaces -o wide --sort-by='{.spec.nodeName}'

      If pods on a node are in an error state, reboot that node.

  11. Complete the following steps only if the migration succeeds and your cluster is in a good state:

    1. To remove the migration annotation from the Cluster Network Operator configuration object, enter the following command:

      $ oc annotate Network.operator.openshift.io cluster \
        networkoperator.openshift.io/network-migration-
    2. To remove the OpenShift SDN network provider namespace, enter the following command:

      $ oc delete namespace openshift-sdn

14.2.3. Additional resources

14.3. Rolling back to the OpenShift SDN network provider

As a cluster administrator, you can rollback to the OpenShift SDN Container Network Interface (CNI) cluster network provider from the OVN-Kubernetes CNI cluster network provider if the migration to OVN-Kubernetes is unsuccessful.

14.3.1. Rolling back the default CNI network provider to OpenShift SDN

As a cluster administrator, you can rollback your cluster to the OpenShift SDN default Container Network Interface (CNI) network provider. During the rollback, you must reboot every node in your cluster.

Important

Only rollback to OpenShift SDN if the migration to OVN-Kubernetes fails.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Access to the cluster as a user with the cluster-admin role.
  • A cluster installed on bare metal infrastructure configured with the OVN-Kubernetes default CNI network provider.

Procedure

  1. To enable the migration, set an annotation on the Cluster Network Operator configuration object by entering the following command:

    $ oc annotate Network.operator.openshift.io cluster \
      'networkoperator.openshift.io/network-migration'=""
  2. Stop all of the machine configuration pools managed by the Machine Config Operator (MCO):

    • Stop the master configuration pool:

      $ oc patch MachineConfigPool master --type='merge' --patch \
        '{ "spec": { "paused": true } }'
    • Stop the worker configuration pool:

      $ oc patch MachineConfigPool worker --type='merge' --patch \
        '{ "spec":{ "paused" :true } }'
  3. To configure the OpenShift SDN cluster network provider, enter the following command:

    $ oc patch Network.config.openshift.io cluster \
      --type='merge' --patch '{ "spec": { "networkType": "OpenShiftSDN" } }'
  4. Optional: You can customize the following settings for OpenShift SDN to meet your network infrastructure requirements:

    • Maximum transmission unit (MTU)
    • VXLAN port

    To customize either or both of the previously noted settings, customize and enter the following command. If you do not need to change the default value, omit the key from the patch.

    $ oc patch Network.operator.openshift.io cluster --type=merge \
      --patch '{
        "spec":{
          "defaultNetwork":{
            "openshiftSDNConfig":{
              "mtu":<mtu>,
              "vxlanPort":<port>
        }}}}'
    mtu
    The MTU for the Geneve overlay network. This value is normally configured automatically, but if the nodes in your cluster do not all use the same MTU, then you must set this explicitly to 100 less than the smallest node MTU value.
    port
    The UDP port for the Geneve overlay network.

    Example patch command

    $ oc patch Network.operator.openshift.io cluster --type=merge \
      --patch '{
        "spec":{
          "defaultNetwork":{
            "openshiftSDNConfig":{
              "mtu":1200
        }}}}'

  5. Wait until the Multus daemon set rollout completes.

    $ oc -n openshift-multus rollout status daemonset/multus

    The name of the Multus pods is in form of multus-<xxxxx> where <xxxxx> is a random sequence of letters. It might take several moments for the pods to restart.

    Example output

    Waiting for daemon set "multus" rollout to finish: 1 out of 6 new pods have been updated...
    ...
    Waiting for daemon set "multus" rollout to finish: 5 of 6 updated pods are available...
    daemon set "multus" successfully rolled out

  6. To complete the rollback, reboot each node in your cluster. For example, you could use a bash script similar to the following. The script assumes that you can connect to each host by using ssh and that you have configured sudo to not prompt for a password.

    #!/bin/bash
    
    for ip in $(oc get nodes  -o jsonpath='{.items[*].status.addresses[?(@.type=="InternalIP")].address}')
    do
       echo "reboot node $ip"
       ssh -o StrictHostKeyChecking=no core@$ip sudo shutdown -r -t 3
    done
  7. After the nodes in your cluster have rebooted, start all of the machine configuration pools:

    • Start the master configuration pool:

      $ oc patch MachineConfigPool master --type='merge' --patch \
        '{ "spec": { "paused": false } }'
    • Start the worker configuration pool:

      $ oc patch MachineConfigPool worker --type='merge' --patch \
        '{ "spec": { "paused": false } }'

    As the MCO updates machines in each config pool, it reboots each node.

    By default the MCO updates a single machine per pool at a time, so the time that the migration requires to complete grows with the size of the cluster.

  8. Confirm the status of the new machine configuration on the hosts:

    1. To list the machine configuration state and the name of the applied machine configuration, enter the following command:

      $ oc describe node | egrep "hostname|machineconfig"

      Example output

      kubernetes.io/hostname=master-0
      machineconfiguration.openshift.io/currentConfig: rendered-master-c53e221d9d24e1c8bb6ee89dd3d8ad7b
      machineconfiguration.openshift.io/desiredConfig: rendered-master-c53e221d9d24e1c8bb6ee89dd3d8ad7b
      machineconfiguration.openshift.io/reason:
      machineconfiguration.openshift.io/state: Done

      Verify that the following statements are true:

      • The value of machineconfiguration.openshift.io/state field is Done.
      • The value of the machineconfiguration.openshift.io/currentConfig field is equal to the value of the machineconfiguration.openshift.io/desiredConfig field.
    2. To confirm that the machine config is correct, enter the following command:

      $ oc get machineconfig <config_name> -o yaml

      where <config_name> is the name of the machine config from the machineconfiguration.openshift.io/currentConfig field.

  9. Confirm that the migration succeeded:

    1. To confirm that the default CNI network provider is OVN-Kubernetes, enter the following command. The value of status.networkType must be OpenShiftSDN.

      $ oc get network.config/cluster -o jsonpath='{.status.networkType}{"\n"}'
    2. To confirm that the cluster nodes are in the Ready state, enter the following command:

      $ oc get nodes
    3. If a node is stuck in the NotReady state, investigate the machine config daemon pod logs and resolve any errors.

      1. To list the pods, enter the following command:

        $ oc get pod -n openshift-machine-config-operator

        Example output

        NAME                                         READY   STATUS    RESTARTS   AGE
        machine-config-controller-75f756f89d-sjp8b   1/1     Running   0          37m
        machine-config-daemon-5cf4b                  2/2     Running   0          43h
        machine-config-daemon-7wzcd                  2/2     Running   0          43h
        machine-config-daemon-fc946                  2/2     Running   0          43h
        machine-config-daemon-g2v28                  2/2     Running   0          43h
        machine-config-daemon-gcl4f                  2/2     Running   0          43h
        machine-config-daemon-l5tnv                  2/2     Running   0          43h
        machine-config-operator-79d9c55d5-hth92      1/1     Running   0          37m
        machine-config-server-bsc8h                  1/1     Running   0          43h
        machine-config-server-hklrm                  1/1     Running   0          43h
        machine-config-server-k9rtx                  1/1     Running   0          43h

        The names for the config daemon pods are in the following format: machine-config-daemon-<seq>. The <seq> value is a random five character alphanumeric sequence.

      2. To display the pod log for each machine config daemon pod shown in the previous output, enter the following command:

        $ oc logs <pod> -n openshift-machine-config-operator

        where pod is the name of a machine config daemon pod.

      3. Resolve any errors in the logs shown by the output from the previous command.
    4. To confirm that your pods are not in an error state, enter the following command:

      $ oc get pods --all-namespaces -o wide --sort-by='{.spec.nodeName}'

      If pods on a node are in an error state, reboot that node.

  10. Complete the following steps only if the migration succeeds and your cluster is in a good state:

    1. To remove the migration annotation from the Cluster Network Operator configuration object, enter the following command:

      $ oc annotate Network.operator.openshift.io cluster \
        networkoperator.openshift.io/network-migration-
    2. To remove the OVN-Kubernetes network provider namespace, enter the following command:

      $ oc delete namespace openshift-ovn-kubernetes

14.4. Configuring an egress firewall for a project

As a cluster administrator, you can create an egress firewall for a project that restricts egress traffic leaving your OpenShift Container Platform cluster.

14.4.1. How an egress firewall works in a project

As a cluster administrator, you can use an egress firewall to limit the external hosts that some or all pods can access from within the cluster. An egress firewall supports the following scenarios:

  • A pod can only connect to internal hosts and cannot initiate connections to the public Internet.
  • A pod can only connect to the public Internet and cannot initiate connections to internal hosts that are outside the OpenShift Container Platform cluster.
  • A pod cannot reach specified internal subnets or hosts outside the OpenShift Container Platform cluster.
  • A pod can connect to only specific external hosts.

For example, you can allow one project access to a specified IP range but deny the same access to a different project. Or you can restrict application developers from updating from Python pip mirrors, and force updates to come only from approved sources.

You configure an egress firewall policy by creating an EgressFirewall custom resource (CR) object. The egress firewall matches network traffic that meets any of the following criteria:

  • An IP address range in CIDR format
  • A port number
  • A protocol that is one of the following protocols: TCP, UDP, and SCTP
Important

If your egress firewall includes a deny rule for 0.0.0.0/0, access to your OpenShift Container Platform API servers is blocked. To ensure that pods can continue to access the OpenShift Container Platform API servers, you must include the IP address range that the API servers listen on in your egress firewall rules, as in the following example:

apiVersion: k8s.ovn.org/v1
kind: EgressFirewall
metadata:
  name: default
  namespace: <namespace> 1
spec:
  egress:
  - to:
      cidrSelector: <api_server_address_range> 2
    type: Allow
# ...
  - to:
      cidrSelector: 0.0.0.0/0 3
    type: Deny
1
The namespace for the egress firewall.
2
The IP address range that includes your OpenShift Container Platform API servers.
3
A global deny rule prevents access to the OpenShift Container Platform API servers.

To find the IP address for your API servers, run oc get ep kubernetes -n default.

For more information, see BZ#1988324.

Warning

Egress firewall rules do not apply to traffic that goes through routers. Any user with permission to create a Route CR object can bypass egress firewall policy rules by creating a route that points to a forbidden destination.

14.4.1.1. Limitations of an egress firewall

An egress firewall has the following limitations:

  • No project can have more than one EgressFirewall object.
  • A maximum of one EgressFirewall object with a maximum of 8,000 rules can be defined per project.

Violating any of these restrictions results in a broken egress firewall for the project, and may cause all external network traffic to be dropped.

14.4.1.2. Matching order for egress firewall policy rules

The egress firewall policy rules are evaluated in the order that they are defined, from first to last. The first rule that matches an egress connection from a pod applies. Any subsequent rules are ignored for that connection.

14.4.2. EgressFirewall custom resource (CR) object

You can define one or more rules for an egress firewall. A rule is either an Allow rule or a Deny rule, with a specification for the traffic that the rule applies to.

The following YAML describes an EgressFirewall CR object:

EgressFirewall object

apiVersion: k8s.ovn.org/v1
kind: EgressFirewall
metadata:
  name: <name> 1
spec:
  egress: 2
    ...

1
The name for the object must be default.
2
A collection of one or more egress network policy rules as described in the following section.

14.4.2.1. EgressFirewall rules

The following YAML describes an egress firewall rule object. The egress stanza expects an array of one or more objects.

Egress policy rule stanza

egress:
- type: <type> 1
  to: 2
    cidrSelector: <cidr> 3
  ports: 4
      ...

1
The type of rule. The value must be either Allow or Deny.
2
A stanza describing an egress traffic match rule.
3
An IP address range in CIDR format.
4
Optional: A stanza describing a collection of network ports and protocols for the rule.

Ports stanza

ports:
- port: <port> 1
  protocol: <protocol> 2

1
A network port, such as 80 or 443. If you specify a value for this field, you must also specify a value for protocol.
2
A network protocol. The value must be either TCP, UDP, or SCTP.

14.4.2.2. Example EgressFirewall CR objects

The following example defines several egress firewall policy rules:

apiVersion: k8s.ovn.org/v1
kind: EgressFirewall
metadata:
  name: default
spec:
  egress: 1
  - type: Allow
    to:
      cidrSelector: 1.2.3.0/24
  - type: Deny
    to:
      cidrSelector: 0.0.0.0/0
1
A collection of egress firewall policy rule objects.

The following example defines a policy rule that denies traffic to the host at the 172.16.1.1 IP address, if the traffic is using either the TCP protocol and destination port 80 or any protocol and destination port 443.

apiVersion: k8s.ovn.org/v1
kind: EgressFirewall
metadata:
  name: default
spec:
  egress:
  - type: Deny
    to:
      cidrSelector: 172.16.1.1
    ports:
    - port: 80
      protocol: TCP
    - port: 443

14.4.3. Creating an egress firewall policy object

As a cluster administrator, you can create an egress firewall policy object for a project.

Important

If the project already has an EgressFirewall object defined, you must edit the existing policy to make changes to the egress firewall rules.

Prerequisites

  • A cluster that uses the OVN-Kubernetes default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift CLI (oc).
  • You must log in to the cluster as a cluster administrator.

Procedure

  1. Create a policy rule:

    1. Create a <policy_name>.yaml file where <policy_name> describes the egress policy rules.
    2. In the file you created, define an egress policy object.
  2. Enter the following command to create the policy object. Replace <policy_name> with the name of the policy and <project> with the project that the rule applies to.

    $ oc create -f <policy_name>.yaml -n <project>

    In the following example, a new EgressFirewall object is created in a project named project1:

    $ oc create -f default.yaml -n project1

    Example output

    egressfirewall.k8s.ovn.org/v1 created

  3. Optional: Save the <policy_name>.yaml file so that you can make changes later.

14.5. Viewing an egress firewall for a project

As a cluster administrator, you can list the names of any existing egress firewalls and view the traffic rules for a specific egress firewall.

14.5.1. Viewing an EgressFirewall object

You can view an EgressFirewall object in your cluster.

Prerequisites

  • A cluster using the OVN-Kubernetes default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift Command-line Interface (CLI), commonly known as oc.
  • You must log in to the cluster.

Procedure

  1. Optional: To view the names of the EgressFirewall objects defined in your cluster, enter the following command:

    $ oc get egressfirewall --all-namespaces
  2. To inspect a policy, enter the following command. Replace <policy_name> with the name of the policy to inspect.

    $ oc describe egressfirewall <policy_name>

    Example output

    Name:		default
    Namespace:	project1
    Created:	20 minutes ago
    Labels:		<none>
    Annotations:	<none>
    Rule:		Allow to 1.2.3.0/24
    Rule:		Allow to www.example.com
    Rule:		Deny to 0.0.0.0/0

14.6. Editing an egress firewall for a project

As a cluster administrator, you can modify network traffic rules for an existing egress firewall.

14.6.1. Editing an EgressFirewall object

As a cluster administrator, you can update the egress firewall for a project.

Prerequisites

  • A cluster using the OVN-Kubernetes default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift CLI (oc).
  • You must log in to the cluster as a cluster administrator.

Procedure

  1. Find the name of the EgressFirewall object for the project. Replace <project> with the name of the project.

    $ oc get -n <project> egressfirewall
  2. Optional: If you did not save a copy of the EgressFirewall object when you created the egress network firewall, enter the following command to create a copy.

    $ oc get -n <project> egressfirewall <name> -o yaml > <filename>.yaml

    Replace <project> with the name of the project. Replace <name> with the name of the object. Replace <filename> with the name of the file to save the YAML to.

  3. After making changes to the policy rules, enter the following command to replace the EgressFirewall object. Replace <filename> with the name of the file containing the updated EgressFirewall object.

    $ oc replace -f <filename>.yaml

14.7. Removing an egress firewall from a project

As a cluster administrator, you can remove an egress firewall from a project to remove all restrictions on network traffic from the project that leaves the OpenShift Container Platform cluster.

14.7.1. Removing an EgressFirewall object

As a cluster administrator, you can remove an egress firewall from a project.

Prerequisites

  • A cluster using the OVN-Kubernetes default Container Network Interface (CNI) network provider plug-in.
  • Install the OpenShift CLI (oc).
  • You must log in to the cluster as a cluster administrator.

Procedure

  1. Find the name of the EgressFirewall object for the project. Replace <project> with the name of the project.

    $ oc get -n <project> egressfirewall
  2. Enter the following command to delete the EgressFirewall object. Replace <project> with the name of the project and <name> with the name of the object.

    $ oc delete -n <project> egressfirewall <name>

14.8. Configuring an egress IP address

As a cluster administrator, you can configure the OVN-Kubernetes default Container Network Interface (CNI) network provider to assign one or more egress IP addresses to a namespace, or to specific pods in a namespace.

14.8.1. Egress IP address architectural design and implementation

The OpenShift Container Platform egress IP address functionality allows you to ensure that the traffic from one or more pods in one or more namespaces has a consistent source IP address for services outside the cluster network.

For example, you might have a pod that periodically queries a database that is hosted on a server outside of your cluster. To enforce access requirements for the server, a packet filtering device is configured to allow traffic only from specific IP addresses. To ensure that you can reliably allow access to the server from only that specific pod, you can configure a specific egress IP address for the pod that makes the requests to the server.

An egress IP address is implemented as an additional IP address on the primary network interface of a node and must be in the same subnet as the primary IP address of the node. The additional IP address must not be assigned to any other node in the cluster.

In some cluster configurations, application pods and ingress router pods run on the same node. If you configure an egress IP for an application project in this scenario, the IP is not used when you send a request to a route from the application project.

14.8.1.1. Platform support

Support for the egress IP address functionality on various platforms is summarized in the following table:

Important

The egress IP address implementation is not compatible with Amazon Web Services (AWS), Azure Cloud, or any other public cloud platform incompatible with the automatic layer 2 network manipulation required by the egress IP feature.

PlatformSupported

Bare metal

Yes

vSphere

Yes

Red Hat OpenStack Platform (RHOSP)

No

Public cloud

No

14.8.1.2. Assignment of egress IPs to pods

To assign one or more egress IPs to a namespace or specific pods in a namespace, the following conditions must be satisfied:

  • At least one node in your cluster must have the k8s.ovn.org/egress-assignable: "" label.
  • An EgressIP object exists that defines one or more egress IP addresses to use as the source IP address for traffic leaving the cluster from pods in a namespace.
Important

If you create EgressIP objects prior to labeling any nodes in your cluster for egress IP assignment, OpenShift Container Platform might assign every egress IP address to the first node with the k8s.ovn.org/egress-assignable: "" label.

To ensure that egress IP addresses are widely distributed across nodes in the cluster, always apply the label to the nodes you intent to host the egress IP addresses before creating any EgressIP objects.

14.8.1.3. Assignment of egress IPs to nodes

When creating an EgressIP object, the following conditions apply to nodes that are labeled with the k8s.ovn.org/egress-assignable: "" label:

  • An egress IP address is never assigned to more than one node at a time.
  • An egress IP address is equally balanced between available nodes that can host the egress IP address.
  • If the spec.EgressIPs array in an EgressIP object specifies more than one IP address, no node will ever host more than one of the specified addresses.
  • If a node becomes unavailable, any egress IP addresses assigned to it are automatically reassigned, subject to the previously described conditions.

When a pod matches the selector for multiple EgressIP objects, there is no guarantee which of the egress IP addresses that are specified in the EgressIP objects is assigned as the egress IP address for the pod.

Additionally, if an EgressIP object specifies multiple egress IP addresses, there is no guarantee which of the egress IP addresses might be used. For example, if a pod matches a selector for an EgressIP object with two egress IP addresses, 10.10.20.1 and 10.10.20.2, either might be used for each TCP connection or UDP conversation.

14.8.1.4. Architectural diagram of an egress IP address configuration

The following diagram depicts an egress IP address configuration. The diagram describes four pods in two different namespaces running on three nodes in a cluster. The nodes are assigned IP addresses from the 192.168.126.0/18 CIDR block on the host network.

Both Node 1 and Node 3 are labeled with k8s.ovn.org/egress-assignable: "" and thus available for the assignment of egress IP addresses.

The dashed lines in the diagram depict the traffic flow from pod1, pod2, and pod3 traveling through the pod network to egress the cluster from Node 1 and Node 3. When an external service receives traffic from any of the pods selected by the example EgressIP object, the source IP address is either 192.168.126.10 or 192.168.126.102.

The following resources from the diagram are illustrated in detail:

Namespace objects

The namespaces are defined in the following manifest:

Namespace objects

apiVersion: v1
kind: Namespace
metadata:
  name: namespace1
  labels:
    env: prod
---
apiVersion: v1
kind: Namespace
metadata:
  name: namespace2
  labels:
    env: prod

EgressIP object

The following EgressIP object describes a configuration that selects all pods in any namespace with the env label set to prod. The egress IP addresses for the selected pods are 192.168.126.10 and 192.168.126.102.

EgressIP object

apiVersion: k8s.ovn.org/v1
kind: EgressIP
metadata:
  name: egressips-prod
spec:
  egressIPs:
  - 192.168.126.10
  - 192.168.126.102
  namespaceSelector:
    matchLabels:
      env: prod
status:
  assignments:
  - node: node1
    egressIP: 192.168.126.10
  - node: node3
    egressIP: 192.168.126.102

For the configuration in the previous example, OpenShift Container Platform assigns both egress IP addresses to the available nodes. The status field reflects whether and where the egress IP addresses are assigned.

14.8.2. EgressIP object

The following YAML describes the API for the EgressIP object. The scope of the object is cluster-wide; it is not created in a namespace.

apiVersion: k8s.ovn.org/v1
kind: EgressIP
metadata:
  name: <name> 1
spec:
  egressIPs: 2
  - <ip_address>
  namespaceSelector: 3
    ...
  podSelector: 4
    ...
1
The name for the EgressIPs object.
2
An array of one or more IP addresses.
3
One or more selectors for the namespaces to associate the egress IP addresses with.
4
Optional: One or more selectors for pods in the specified namespaces to associate egress IP addresses with. Applying these selectors allows for the selection of a subset of pods within a namespace.

The following YAML describes the stanza for the namespace selector:

Namespace selector stanza

namespaceSelector: 1
  matchLabels:
    <label_name>: <label_value>

1
One or more matching rules for namespaces. If more than one match rule is provided, all matching namespaces are selected.

The following YAML describes the optional stanza for the pod selector:

Pod selector stanza

podSelector: 1
  matchLabels:
    <label_name>: <label_value>

1
Optional: One or more matching rules for pods in the namespaces that match the specified namespaceSelector rules. If specified, only pods that match are selected. Others pods in the namespace are not selected.

In the following example, the EgressIP object associates the 192.168.126.11 and 192.168.126.102 egress IP addresses with pods that have the app label set to web and are in the namespaces that have the env label set to prod:

Example EgressIP object

apiVersion: k8s.ovn.org/v1
kind: EgressIP
metadata:
  name: egress-group1
spec:
  egressIPs:
  - 192.168.126.11
  - 192.168.126.102
  podSelector:
    matchLabels:
      app: web
  namespaceSelector:
    matchLabels:
      env: prod

In the following example, the EgressIP object associates the 192.168.127.30 and 192.168.127.40 egress IP addresses with any pods that do not have the environment label set to development:

Example EgressIP object

apiVersion: k8s.ovn.org/v1
kind: EgressIP
metadata:
  name: egress-group2
spec:
  egressIPs:
  - 192.168.127.30
  - 192.168.127.40
  namespaceSelector:
    matchExpressions:
    - key: environment
      operator: NotIn
      values:
      - development

14.8.3. Labeling a node to host egress IP addresses

You can apply the k8s.ovn.org/egress-assignable="" label to a node in your cluster so that OpenShift Container Platform can assign one or more egress IP addresses to the node.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in to the cluster as a cluster administrator.

Procedure

  • To label a node so that it can host one or more egress IP addresses, enter the following command:

    $ oc label nodes <node_name> k8s.ovn.org/egress-assignable="" 1
    1
    The name of the node to label.

14.8.4. Next steps

14.8.5. Additional resources

14.9. Assigning an egress IP address

As a cluster administrator, you can assign an egress IP address for traffic leaving the cluster from a namespace or from specific pods in a namespace.

14.9.1. Assigning an egress IP address to a namespace

You can assign one or more egress IP addresses to a namespace or to specific pods in a namespace.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Log in to the cluster as a cluster administrator.
  • Configure at least one node to host an egress IP address.

Procedure

  1. Create an EgressIP object:

    1. Create a <egressips_name>.yaml file where <egressips_name> is the name of the object.
    2. In the file that you created, define an EgressIP object, as in the following example:

      apiVersion: k8s.ovn.org/v1
      kind: EgressIP
      metadata:
        name: egress-project1
      spec:
        egressIPs:
        - 192.168.127.10
        - 192.168.127.11
        namespaceSelector:
          matchLabels:
            env: qa
  2. To create the object, enter the following command.

    $ oc apply -f <egressips_name>.yaml 1
    1
    Replace <egressips_name> with the name of the object.

    Example output

    egressips.k8s.ovn.org/<egressips_name> created

  3. Optional: Save the <egressips_name>.yaml file so that you can make changes later.
  4. Add labels to the namespace that requires egress IP addresses. To add a label to the namespace of an EgressIP object defined in step 1, run the following command:

    $ oc label ns <namespace> env=qa 1
    1
    Replace <namespace> with the namespace that requires egress IP addresses.

14.9.2. Additional resources

14.10. Enabling multicast for a project

14.10.1. About multicast

With IP multicast, data is broadcast to many IP addresses simultaneously.

Important

At this time, multicast is best used for low-bandwidth coordination or service discovery and not a high-bandwidth solution.

Multicast traffic between OpenShift Container Platform pods is disabled by default. If you are using the OVN-Kubernetes default Container Network Interface (CNI) network provider, you can enable multicast on a per-project basis.

14.10.2. Enabling multicast between pods

You can enable multicast between pods for your project.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  • Run the following command to enable multicast for a project. Replace <namespace> with the namespace for the project you want to enable multicast for.

    $ oc annotate namespace <namespace> \
        k8s.ovn.org/multicast-enabled=true

Verification

To verify that multicast is enabled for a project, complete the following procedure:

  1. Change your current project to the project that you enabled multicast for. Replace <project> with the project name.

    $ oc project <project>
  2. Create a pod to act as a multicast receiver:

    $ cat <<EOF| oc create -f -
    apiVersion: v1
    kind: Pod
    metadata:
      name: mlistener
      labels:
        app: multicast-verify
    spec:
      containers:
        - name: mlistener
          image: registry.access.redhat.com/ubi8
          command: ["/bin/sh", "-c"]
          args:
            ["dnf -y install socat hostname && sleep inf"]
          ports:
            - containerPort: 30102
              name: mlistener
              protocol: UDP
    EOF
  3. Create a pod to act as a multicast sender:

    $ cat <<EOF| oc create -f -
    apiVersion: v1
    kind: Pod
    metadata:
      name: msender
      labels:
        app: multicast-verify
    spec:
      containers:
        - name: msender
          image: registry.access.redhat.com/ubi8
          command: ["/bin/sh", "-c"]
          args:
            ["dnf -y install socat && sleep inf"]
    EOF
  4. In a new terminal window or tab, start the multicast listener.

    1. Get the IP address for the Pod:

      $ POD_IP=$(oc get pods mlistener -o jsonpath='{.status.podIP}')
    2. Start the multicast listener by entering the following command:

      $ oc exec mlistener -i -t -- \
          socat UDP4-RECVFROM:30102,ip-add-membership=224.1.0.1:$POD_IP,fork EXEC:hostname
  5. Start the multicast transmitter.

    1. Get the pod network IP address range:

      $ CIDR=$(oc get Network.config.openshift.io cluster \
          -o jsonpath='{.status.clusterNetwork[0].cidr}')
    2. To send a multicast message, enter the following command:

      $ oc exec msender -i -t -- \
          /bin/bash -c "echo | socat STDIO UDP4-DATAGRAM:224.1.0.1:30102,range=$CIDR,ip-multicast-ttl=64"

      If multicast is working, the previous command returns the following output:

      mlistener

14.11. Disabling multicast for a project

14.11.1. Disabling multicast between pods

You can disable multicast between pods for your project.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has the cluster-admin role.

Procedure

  • Disable multicast by running the following command:

    $ oc annotate namespace <namespace> \ 1
        k8s.ovn.org/multicast-enabled-
    1
    The namespace for the project you want to disable multicast for.

14.12. Configuring hybrid networking

As a cluster administrator, you can configure the OVN-Kubernetes Container Network Interface (CNI) cluster network provider to allow Linux and Windows nodes to host Linux and Windows workloads, respectively.

14.12.1. Configuring hybrid networking with OVN-Kubernetes

You can configure your cluster to use hybrid networking with OVN-Kubernetes. This allows a hybrid cluster that supports different node networking configurations. For example, this is necessary to run both Linux and Windows nodes in a cluster.

Important

You must configure hybrid networking with OVN-Kubernetes during the installation of your cluster. You cannot switch to hybrid networking after the installation process.

Prerequisites

  • You defined OVNKubernetes for the networking.networkType parameter in the install-config.yaml file. See the installation documentation for configuring OpenShift Container Platform network customizations on your chosen cloud provider for more information.

Procedure

  1. Change to the directory that contains the installation program and create the manifests:

    $ ./openshift-install create manifests --dir <installation_directory>

    where:

    <installation_directory>
    Specifies the name of the directory that contains the install-config.yaml file for your cluster.
  2. Create a stub manifest file for the advanced network configuration that is named cluster-network-03-config.yml in the <installation_directory>/manifests/ directory:

    $ cat <<EOF > <installation_directory>/manifests/cluster-network-03-config.yml
    apiVersion: operator.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
    EOF

    where:

    <installation_directory>
    Specifies the directory name that contains the manifests/ directory for your cluster.
  3. Open the cluster-network-03-config.yml file in an editor and configure OVN-Kubernetes with hybrid networking, such as in the following example:

    Specify a hybrid networking configuration

    apiVersion: operator.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      defaultNetwork:
        ovnKubernetesConfig:
          hybridOverlayConfig:
            hybridClusterNetwork: 1
            - cidr: 10.132.0.0/14
              hostPrefix: 23
            hybridOverlayVXLANPort: 9898 2

    1
    Specify the CIDR configuration used for nodes on the additional overlay network. The hybridClusterNetwork CIDR cannot overlap with the clusterNetwork CIDR.
    2
    Specify a custom VXLAN port for the additional overlay network. This is required for running Windows nodes in a cluster installed on vSphere, and must not be configured for any other cloud provider. The custom port can be any open port excluding the default 4789 port. For more information on this requirement, see the Microsoft documentation on Pod-to-pod connectivity between hosts is broken.
  4. Save the cluster-network-03-config.yml file and quit the text editor.
  5. Optional: Back up the manifests/cluster-network-03-config.yml file. The installation program deletes the manifests/ directory when creating the cluster.

Complete any further installation configurations, and then create your cluster. Hybrid networking is enabled when the installation process is finished.

14.12.2. Additional resources

Chapter 15. Configuring Routes

15.1. Route configuration

15.1.1. Creating an HTTP-based route

A route allows you to host your application at a public URL. It can either be secure or unsecured, depending on the network security configuration of your application. An HTTP-based route is an unsecured route that uses the basic HTTP routing protocol and exposes a service on an unsecured application port.

The following procedure describes how to create a simple HTTP-based route to a web application, using the hello-openshift application as an example.

Prerequisites

  • You installed the OpenShift CLI (oc).
  • You are logged in as an administrator.
  • You have a web application that exposes a port and a TCP endpoint listening for traffic on the port.

Procedure

  1. Create a project called hello-openshift by running the following command:

    $ oc new-project hello-openshift
  2. Create a pod in the project by running the following command:

    $ oc create -f https://raw.githubusercontent.com/openshift/origin/master/examples/hello-openshift/hello-pod.json
  3. Create a service called hello-openshift by running the following command:

    $ oc expose pod/hello-openshift
  4. Create an unsecured route to the hello-openshift application by running the following command:

    $ oc expose svc hello-openshift

    If you examine the resulting Route resource, it should look similar to the following:

    YAML definition of the created unsecured route:

    apiVersion: route.openshift.io/v1
    kind: Route
    metadata:
      name: hello-openshift
    spec:
      host: hello-openshift-hello-openshift.<Ingress_Domain> 1
      port:
        targetPort: 8080
      to:
        kind: Service
        name: hello-openshift

    1
    <Ingress_Domain> is the default ingress domain name.
    Note

    To display your default ingress domain, run the following command:

    $ oc get ingresses.config/cluster -o jsonpath={.spec.domain}

15.1.2. Configuring route timeouts

You can configure the default timeouts for an existing route when you have services in need of a low timeout, which is required for Service Level Availability (SLA) purposes, or a high timeout, for cases with a slow back end.

Prerequisites

  • You need a deployed Ingress Controller on a running cluster.

Procedure

  1. 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> 1
    1
    Supported time units are microseconds (us), milliseconds (ms), seconds (s), minutes (m), hours (h), or days (d).

    The following example sets a timeout of two seconds on a route named myroute:

    $ oc annotate route myroute --overwrite haproxy.router.openshift.io/timeout=2s

15.1.3. Enabling HTTP strict transport security

HTTP Strict Transport Security (HSTS) policy is a security enhancement, which ensures that only HTTPS traffic is allowed on the host. Any HTTP requests are dropped by default. This is useful for ensuring secure interactions with websites, or to offer a secure application for the user’s benefit.

When HSTS is enabled, HSTS adds a Strict Transport Security header to HTTPS responses from the site. You can use the insecureEdgeTerminationPolicy value in a route to redirect to send HTTP to HTTPS. However, when HSTS is enabled, the client changes all requests from the HTTP URL to HTTPS before the request is sent, eliminating the need for a redirect. This is not required to be supported by the client, and can be disabled by setting max-age=0.

Important

HSTS works only with secure routes (either edge terminated or re-encrypt). The configuration is ineffective on HTTP or passthrough routes.

Procedure

  • To enable HSTS on a route, add the haproxy.router.openshift.io/hsts_header value to the edge terminated or re-encrypt route:

    apiVersion: v1
    kind: Route
    metadata:
      annotations:
        haproxy.router.openshift.io/hsts_header: max-age=31536000;includeSubDomains;preload 1 2 3
    1
    max-age is the only required parameter. It measures the length of time, in seconds, that the HSTS policy is in effect. The client updates max-age whenever a response with a HSTS header is received from the host. When max-age times out, the client discards the policy.
    2
    includeSubDomains is optional. When included, it tells the client that all subdomains of the host are to be treated the same as the host.
    3
    preload is optional. When max-age is greater than 0, then including preload in haproxy.router.openshift.io/hsts_header allows external services to include this site in their HSTS preload lists. For example, sites such as Google can construct a list of sites that have preload set. Browsers can then use these lists to determine which sites they can communicate with over HTTPS, before they have interacted with the site. Without preload set, browsers must have interacted with the site over HTTPS to get the header.

15.1.4. Troubleshooting throughput issues

Sometimes applications deployed through OpenShift Container Platform can cause network throughput issues such as unusually high latency between specific services.

Use the following methods to analyze performance issues if pod logs do not reveal any cause of the problem:

  • Use a packet analyzer, such as ping or tcpdump to analyze traffic between a pod and its node.

    For example, run the tcpdump tool on each pod while reproducing the behavior that led to the issue. Review the captures on both sides to compare send and receive timestamps to analyze the latency of traffic to and from a pod. Latency can occur in OpenShift Container Platform if a node interface is overloaded with traffic from other pods, storage devices, or the data plane.

    $ tcpdump -s 0 -i any -w /tmp/dump.pcap host <podip 1> && host <podip 2> 1
    1
    podip is the IP address for the pod. Run the oc get pod <pod_name> -o wide command to get the IP address of a pod.

    tcpdump generates a file at /tmp/dump.pcap containing all traffic between these two pods. Ideally, run the analyzer shortly before the issue is reproduced and stop the analyzer shortly after the issue is finished reproducing to minimize the size of the file. You can also run a packet analyzer between the nodes (eliminating the SDN from the equation) with:

    $ tcpdump -s 0 -i any -w /tmp/dump.pcap port 4789
  • Use a bandwidth measuring tool, such as iperf, to measure streaming throughput and UDP throughput. Run the tool from the pods first, then from the nodes, to locate any bottlenecks.

15.1.5. Using cookies to keep route statefulness

OpenShift Container Platform provides sticky sessions, which enables stateful application traffic by ensuring all traffic hits the same endpoint. However, if the endpoint pod terminates, whether through restart, scaling, or a change in configuration, this statefulness can disappear.

OpenShift Container Platform can use cookies to configure session persistence. The Ingress controller selects an endpoint to handle any user requests, and creates a cookie for the session. The cookie is passed back in the response to the request and the user sends the cookie back with the next request in the session. The cookie tells the Ingress Controller which endpoint is handling the session, ensuring that client requests use the cookie so that they are routed to the same pod.

Note

Cookies cannot be set on passthrough routes, because the HTTP traffic cannot be seen. Instead, a number is calculated based on the source IP address, which determines the backend.

If backends change, the traffic can be directed to the wrong server, making it less sticky. If you are using a load balancer, which hides source IP, the same number is set for all connections and traffic is sent to the same pod.

15.1.6. Path-based routes

Path-based routes specify a path component that can be compared against a URL, which requires that the traffic for the route be HTTP based. Thus, multiple routes can be served using the same hostname, each with a different path. Routers should match routes based on the most specific path to the least. However, this depends on the router implementation.

The following table shows example routes and their accessibility:

Table 15.1. Route availability

RouteWhen Compared toAccessible

www.example.com/test

www.example.com/test

Yes

www.example.com

No

www.example.com/test and www.example.com

www.example.com/test

Yes

www.example.com

Yes

www.example.com

www.example.com/text

Yes (Matched by the host, not the route)

www.example.com

Yes

An unsecured route with a path

apiVersion: v1
kind: Route
metadata:
  name: route-unsecured
spec:
  host: www.example.com
  path: "/test" 1
  to:
    kind: Service
    name: service-name

1
The path is the only added attribute for a path-based route.
Note

Path-based routing is not available when using passthrough TLS, as the router does not terminate TLS in that case and cannot read the contents of the request.

15.1.7. Route-specific annotations

The Ingress Controller can set the default options for all the routes it exposes. An individual route can override some of these defaults by providing specific configurations in its annotations. Red Hat does not support adding a route annotation to an operator-managed route.

Important

To create a whitelist with multiple source IPs or subnets, use a space-delimited list. Any other delimiter type causes the list to be ignored without a warning or error message.

Table 15.2. Route annotations

VariableDescriptionEnvironment variable used as default

haproxy.router.openshift.io/balance

Sets the load-balancing algorithm. Available options are source, roundrobin, and leastconn.

ROUTER_TCP_BALANCE_SCHEME for passthrough routes. Otherwise, use ROUTER_LOAD_BALANCE_ALGORITHM.

haproxy.router.openshift.io/disable_cookies

Disables the use of cookies to track related connections. If set to true or TRUE, the balance algorithm is used to choose which back-end serves connections for each incoming HTTP request.

 

router.openshift.io/cookie_name

Specifies an optional cookie to use for this route. The name must consist of any combination of upper and lower case letters, digits, "_", and "-". The default is the hashed internal key name for the route.

 

haproxy.router.openshift.io/pod-concurrent-connections

Sets the maximum number of connections that are allowed to a backing pod from a router.
Note: If there are multiple pods, each can have this many connections. If you have multiple routers, there is no coordination among them, each may connect this many times. If not set, or set to 0, there is no limit.

 

haproxy.router.openshift.io/rate-limit-connections

Setting true or TRUE enables rate limiting functionality which is implemented through stick-tables on the specific backend per route.
Note: Using this annotation provides basic protection against distributed denial-of-service (DDoS) attacks.

 

haproxy.router.openshift.io/rate-limit-connections.concurrent-tcp

Limits the number of concurrent TCP connections made through the same source IP address. It accepts a numeric value.
Note: Using this annotation provides basic protection against distributed denial-of-service (DDoS) attacks.

 

haproxy.router.openshift.io/rate-limit-connections.rate-http

Limits the rate at which a client with the same source IP address can make HTTP requests. It accepts a numeric value.
Note: Using this annotation provides basic protection against distributed denial-of-service (DDoS) attacks.

 

haproxy.router.openshift.io/rate-limit-connections.rate-tcp

Limits the rate at which a client with the same source IP address can make TCP connections. It accepts a numeric value.
Note: Using this annotation provides basic protection against distributed denial-of-service (DDoS) attacks.

 

haproxy.router.openshift.io/timeout

Sets a server-side timeout for the route. (TimeUnits)

ROUTER_DEFAULT_SERVER_TIMEOUT

haproxy.router.openshift.io/timeout-tunnel

This timeout applies to a tunnel connection, for example, WebSocket over cleartext, edge, reencrypt, or passthrough routes. With cleartext, edge, or reencrypt route types, this annotation is applied as a timeout tunnel with the existing timeout value. For the passthrough route types, the annotation takes precedence over any existing timeout value set.

ROUTER_DEFAULT_TUNNEL_TIMEOUT

ingresses.config/cluster ingress.operator.openshift.io/hard-stop-after

You can set either an IngressController or the ingress config . This annotation redeploys the router and configures the HA proxy to emit the haproxy hard-stop-after global option, which defines the maximum time allowed to perform a clean soft-stop.

ROUTER_HARD_STOP_AFTER

router.openshift.io/haproxy.health.check.interval

Sets the interval for the back-end health checks. (TimeUnits)

ROUTER_BACKEND_CHECK_INTERVAL

haproxy.router.openshift.io/ip_whitelist

Sets a whitelist for the route. The whitelist is a space-separated list of IP addresses and CIDR ranges for the approved source addresses. Requests from IP addresses that are not in the whitelist are dropped.

The maximum number of IP addresses and CIDR ranges allowed in a whitelist is 61.

 

haproxy.router.openshift.io/hsts_header

Sets a Strict-Transport-Security header for the edge terminated or re-encrypt route.

 

haproxy.router.openshift.io/log-send-hostname

Sets the hostname field in the Syslog header. Uses the hostname of the system. log-send-hostname is enabled by default if any Ingress API logging method, such as sidecar or Syslog facility, is enabled for the router.

 

haproxy.router.openshift.io/rewrite-target

Sets the rewrite path of the request on the backend.

 

router.openshift.io/cookie-same-site

Sets a value to restrict cookies. The values are:

Lax: cookies are transferred between the visited site and third-party sites.

Strict: cookies are restricted to the visited site.

None: cookies are restricted to the visited site.

This value is applicable to re-encrypt and edge routes only. For more information, see the SameSite cookies documentation.

 

haproxy.router.openshift.io/set-forwarded-headers

Sets the policy for handling the Forwarded and X-Forwarded-For HTTP headers per route. The values are:

append: appends the header, preserving any existing header. This is the default value.

replace: sets the header, removing any existing header.

never: never sets the header, but preserves any existing header.

if-none: sets the header if it is not already set.

ROUTER_SET_FORWARDED_HEADERS

Note

Environment variables cannot be edited.

Router timeout variables

TimeUnits are represented by a number followed by the unit: us *(microseconds), ms (milliseconds, default), s (seconds), m (minutes), h *(hours), d (days).

The regular expression is: [1-9][0-9]*(us\|ms\|s\|m\|h\|d).

VariableDefaultDescription

ROUTER_BACKEND_CHECK_INTERVAL

5000ms

Length of time between subsequent liveness checks on back ends.

ROUTER_CLIENT_FIN_TIMEOUT

1s

Controls the TCP FIN timeout period for the client connecting to the route. If the FIN sent to close the connection does not answer within the given time, HAProxy closes the connection. This is harmless if set to a low value and uses fewer resources on the router.

ROUTER_DEFAULT_CLIENT_TIMEOUT

30s

Length of time that a client has to acknowledge or send data.

ROUTER_DEFAULT_CONNECT_TIMEOUT

5s

The maximum connection time.

ROUTER_DEFAULT_SERVER_FIN_TIMEOUT

1s

Controls the TCP FIN timeout from the router to the pod backing the route.

ROUTER_DEFAULT_SERVER_TIMEOUT

30s

Length of time that a server has to acknowledge or send data.

ROUTER_DEFAULT_TUNNEL_TIMEOUT

1h

Length of time for TCP or WebSocket connections to remain open. This timeout period resets whenever HAProxy reloads.

ROUTER_SLOWLORIS_HTTP_KEEPALIVE

300s

Set the maximum time to wait for a new HTTP request to appear. If this is set too low, it can cause problems with browsers and applications not expecting a small keepalive value.

Some effective timeout values can be the sum of certain variables, rather than the specific expected timeout. For example, ROUTER_SLOWLORIS_HTTP_KEEPALIVE adjusts timeout http-keep-alive. It is set to 300s by default, but HAProxy also waits on tcp-request inspect-delay, which is set to 5s. In this case, the overall timeout would be 300s plus 5s.

ROUTER_SLOWLORIS_TIMEOUT

10s

Length of time the transmission of an HTTP request can take.

RELOAD_INTERVAL

5s

Allows the minimum frequency for the router to reload and accept new changes.

ROUTER_METRICS_HAPROXY_TIMEOUT

5s

Timeout for the gathering of HAProxy metrics.

A route setting custom timeout

apiVersion: v1
kind: Route
metadata:
  annotations:
    haproxy.router.openshift.io/timeout: 5500ms 1
...

1
Specifies the new timeout with HAProxy supported units (us, ms, s, m, h, d). If the unit is not provided, ms is the default.
Note

Setting a server-side timeout value for passthrough routes too low can cause WebSocket connections to timeout frequently on that route.

A route that allows only one specific IP address

metadata:
  annotations:
    haproxy.router.openshift.io/ip_whitelist: 192.168.1.10

A route that allows several IP addresses

metadata:
  annotations:
    haproxy.router.openshift.io/ip_whitelist: 192.168.1.10 192.168.1.11 192.168.1.12

A route that allows an IP address CIDR network

metadata:
  annotations:
    haproxy.router.openshift.io/ip_whitelist: 192.168.1.0/24

A route that allows both IP an address and IP address CIDR networks

metadata:
  annotations:
    haproxy.router.openshift.io/ip_whitelist: 180.5.61.153 192.168.1.0/24 10.0.0.0/8

A route specifying a rewrite target

apiVersion: v1
kind: Route
metadata:
  annotations:
    haproxy.router.openshift.io/rewrite-target: / 1
...

1
Sets / as rewrite path of the request on the backend.

Setting the haproxy.router.openshift.io/rewrite-target annotation on a route specifies that the Ingress Controller should rewrite paths in HTTP requests using this route before forwarding the requests to the backend application. The part of the request path that matches the path specified in spec.path is replaced with the rewrite target specified in the annotation.

The following table provides examples of the path rewriting behavior for various combinations of spec.path, request path, and rewrite target.

Table 15.3. rewrite-target examples:

Route.spec.pathRequest pathRewrite targetForwarded request path

/foo

/foo

/

/

/foo

/foo/

/

/

/foo

/foo/bar

/

/bar

/foo

/foo/bar/

/

/bar/

/foo

/foo

/bar

/bar

/foo

/foo/

/bar

/bar/

/foo

/foo/bar

/baz

/baz/bar

/foo

/foo/bar/

/baz

/baz/bar/

/foo/

/foo

/

N/A (request path does not match route path)

/foo/

/foo/

/

/

/foo/

/foo/bar

/

/bar

15.1.8. Configuring the route admission policy

Administrators and application developers can run applications in multiple namespaces with the same domain name. This is for organizations where multiple teams develop microservices that are exposed on the same hostname.

Warning

Allowing claims across namespaces should only be enabled for clusters with trust between namespaces, otherwise a malicious user could take over a hostname. For this reason, the default admission policy disallows hostname claims across namespaces.

Prerequisites

  • Cluster administrator privileges.

Procedure

  • Edit the .spec.routeAdmission field of the ingresscontroller resource variable using the following command:

    $ oc -n openshift-ingress-operator patch ingresscontroller/default --patch '{"spec":{"routeAdmission":{"namespaceOwnership":"InterNamespaceAllowed"}}}' --type=merge

    Sample Ingress Controller configuration

    spec:
      routeAdmission:
        namespaceOwnership: InterNamespaceAllowed
    ...

15.1.9. Creating a route through an Ingress object

Some ecosystem components have an integration with Ingress resources but not with route resources. To cover this case, OpenShift Container Platform automatically creates managed route objects when an Ingress object is created. These route objects are deleted when the corresponding Ingress objects are deleted.

Procedure

  1. Define an Ingress object in the OpenShift Container Platform console or by entering the oc create command:

    YAML Definition of an Ingress

    apiVersion: networking.k8s.io/v1
    kind: Ingress
    metadata:
      name: frontend
      annotations:
        route.openshift.io/termination: "reencrypt" 1
    spec:
      rules:
      - host: www.example.com
        http:
          paths:
          - backend:
              service:
                name: frontend
                port:
                  number: 443
            path: /
            pathType: Prefix
      tls:
      - hosts:
        - www.example.com
        secretName: example-com-tls-certificate

    1
    The route.openshift.io/termination annotation can be used to configure the spec.tls.termination field of the Route as Ingress has no field for this. The accepted values are edge, passthrough and reencrypt. All other values are silently ignored. When the annotation value is unset, edge is the default route. The TLS certificate details must be defined in the template file to implement the default edge route.
    1. If you specify the passthrough value in the route.openshift.io/termination annotation, set path to '' and pathType to ImplementationSpecific in the spec:

        spec:
          rules:
          - host: www.example.com
            http:
              paths:
              - path: ''
                pathType: ImplementationSpecific
                backend:
                  service:
                    name: frontend
                    port:
                      number: 443
    $ oc apply -f ingress.yaml
  2. List your routes:

    $ oc get routes

    The result includes an autogenerated route whose name starts with frontend-:

    NAME             HOST/PORT         PATH    SERVICES    PORT    TERMINATION          WILDCARD
    frontend-gnztq   www.example.com           frontend    443     reencrypt/Redirect   None

    If you inspect this route, it looks this:

    YAML Definition of an autogenerated route

    apiVersion: route.openshift.io/v1
    kind: Route
    metadata:
      name: frontend-gnztq
      ownerReferences:
      - apiVersion: networking.k8s.io/v1
        controller: true
        kind: Ingress
        name: frontend
        uid: 4e6c59cc-704d-4f44-b390-617d879033b6
    spec:
      host: www.example.com
      path: /
      port:
        targetPort: https
      tls:
        certificate: |
          -----BEGIN CERTIFICATE-----
          [...]
          -----END CERTIFICATE-----
        insecureEdgeTerminationPolicy: Redirect
        key: |
          -----BEGIN RSA PRIVATE KEY-----
          [...]
          -----END RSA PRIVATE KEY-----
        termination: reencrypt
      to:
        kind: Service
        name: frontend

15.2. Secured routes

Secure routes provide the ability to use several types of TLS termination to serve certificates to the client. The following sections describe how to create re-encrypt, edge, and passthrough routes with custom certificates.

Important

If you create routes in Microsoft Azure through public endpoints, the resource names are subject to restriction. You cannot create resources that use certain terms. For a list of terms that Azure restricts, see Resolve reserved resource name errors in the Azure documentation.

15.2.1. Creating a re-encrypt route with a custom certificate

You can configure a secure route using reencrypt TLS termination with a custom certificate by using the oc create route command.

Prerequisites

  • You must have a certificate/key pair in PEM-encoded files, where the certificate is valid for the route host.
  • You may have a separate CA certificate in a PEM-encoded file that completes the certificate chain.
  • You must have a separate destination CA certificate in a PEM-encoded file.
  • You must have a service that you want to expose.
Note

Password protected key files are not supported. To remove a passphrase from a key file, use the following command:

$ openssl rsa -in password_protected_tls.key -out tls.key

Procedure

This procedure creates a Route resource with a custom certificate and reencrypt TLS termination. The following assumes that the certificate/key pair are in the tls.crt and tls.key files in the current working directory. You must also specify a destination CA certificate to enable the Ingress Controller to trust the service’s certificate. You may also specify a CA certificate if needed to complete the certificate chain. Substitute the actual path names for tls.crt, tls.key, cacert.crt, and (optionally) ca.crt. Substitute the name of the Service resource that you want to expose for frontend. Substitute the appropriate hostname for www.example.com.

  • Create a secure Route resource using reencrypt TLS termination and a custom certificate:

    $ oc create route reencrypt --service=frontend --cert=tls.crt --key=tls.key --dest-ca-cert=destca.crt --ca-cert=ca.crt --hostname=www.example.com

    If you examine the resulting Route resource, it should look similar to the following:

    YAML Definition of the Secure Route

    apiVersion: v1
    kind: Route
    metadata:
      name: frontend
    spec:
      host: www.example.com
      to:
        kind: Service
        name: frontend
      tls:
        termination: reencrypt
        key: |-
          -----BEGIN PRIVATE KEY-----
          [...]
          -----END PRIVATE KEY-----
        certificate: |-
          -----BEGIN CERTIFICATE-----
          [...]
          -----END CERTIFICATE-----
        caCertificate: |-
          -----BEGIN CERTIFICATE-----
          [...]
          -----END CERTIFICATE-----
        destinationCACertificate: |-
          -----BEGIN CERTIFICATE-----
          [...]
          -----END CERTIFICATE-----

    See oc create route reencrypt --help for more options.

15.2.2. Creating an edge route with a custom certificate

You can configure a secure route using edge TLS termination with a custom certificate by using the oc create route command. With an edge route, the Ingress Controller terminates TLS encryption before forwarding traffic to the destination pod. The route specifies the TLS certificate and key that the Ingress Controller uses for the route.

Prerequisites

  • You must have a certificate/key pair in PEM-encoded files, where the certificate is valid for the route host.
  • You may have a separate CA certificate in a PEM-encoded file that completes the certificate chain.
  • You must have a service that you want to expose.
Note

Password protected key files are not supported. To remove a passphrase from a key file, use the following command:

$ openssl rsa -in password_protected_tls.key -out tls.key

Procedure

This procedure creates a Route resource with a custom certificate and edge TLS termination. The following assumes that the certificate/key pair are in the tls.crt and tls.key files in the current working directory. You may also specify a CA certificate if needed to complete the certificate chain. Substitute the actual path names for tls.crt, tls.key, and (optionally) ca.crt. Substitute the name of the service that you want to expose for frontend. Substitute the appropriate hostname for www.example.com.

  • Create a secure Route resource using edge TLS termination and a custom certificate.

    $ oc create route edge --service=frontend --cert=tls.crt --key=tls.key --ca-cert=ca.crt --hostname=www.example.com

    If you examine the resulting Route resource, it should look similar to the following:

    YAML Definition of the Secure Route

    apiVersion: v1
    kind: Route
    metadata:
      name: frontend
    spec:
      host: www.example.com
      to:
        kind: Service
        name: frontend
      tls:
        termination: edge
        key: |-
          -----BEGIN PRIVATE KEY-----
          [...]
          -----END PRIVATE KEY-----
        certificate: |-
          -----BEGIN CERTIFICATE-----
          [...]
          -----END CERTIFICATE-----
        caCertificate: |-
          -----BEGIN CERTIFICATE-----
          [...]
          -----END CERTIFICATE-----

    See oc create route edge --help for more options.

15.2.3. Creating a passthrough route

You can configure a secure route using passthrough termination by using the oc create route command. With passthrough termination, encrypted traffic is sent straight to the destination without the router providing TLS termination. Therefore no key or certificate is required on the route.

Prerequisites

  • You must have a service that you want to expose.

Procedure

  • Create a Route resource:

    $ oc create route passthrough route-passthrough-secured --service=frontend --port=8080

    If you examine the resulting Route resource, it should look similar to the following:

    A Secured Route Using Passthrough Termination

    apiVersion: v1
    kind: Route
    metadata:
      name: route-passthrough-secured 1
    spec:
      host: www.example.com
      port:
        targetPort: 8080
      tls:
        termination: passthrough 2
        insecureEdgeTerminationPolicy: None 3
      to:
        kind: Service
        name: frontend

    1
    The name of the object, which is limited to 63 characters.
    2
    The termination field is set to passthrough. This is the only required tls field.
    3
    Optional insecureEdgeTerminationPolicy. The only valid values are None, Redirect, or empty for disabled.

    The destination pod is responsible for serving certificates for the traffic at the endpoint. This is currently the only method that can support requiring client certificates, also known as two-way authentication.

Chapter 16. Configuring ingress cluster traffic

16.1. Configuring ingress cluster traffic overview

OpenShift Container Platform provides the following methods for communicating from outside the cluster with services running in the cluster.

The methods are recommended, in order or preference:

  • If you have HTTP/HTTPS, use an Ingress Controller.
  • If you have a TLS-encrypted protocol other than HTTPS. For example, for TLS with the SNI header, use an Ingress Controller.
  • Otherwise, use a Load Balancer, an External IP, or a NodePort.
MethodPurpose

Use an Ingress Controller

Allows access to HTTP/HTTPS traffic and TLS-encrypted protocols other than HTTPS (for example, TLS with the SNI header).

Automatically assign an external IP using a load balancer service

Allows traffic to non-standard ports through an IP address assigned from a pool.

Manually assign an external IP to a service

Allows traffic to non-standard ports through a specific IP address.

Configure a NodePort

Expose a service on all nodes in the cluster.

16.2. Configuring ExternalIPs for services

As a cluster administrator, you can designate an IP address block that is external to the cluster that can send traffic to services in the cluster.

This functionality is generally most useful for clusters installed on bare-metal hardware.

16.2.1. Prerequisites

  • Your network infrastructure must route traffic for the external IP addresses to your cluster.

16.2.2. About ExternalIP

For non-cloud environments, OpenShift Container Platform supports the assignment of external IP addresses to a Service object spec.externalIPs[] field through the ExternalIP facility. By setting this field, OpenShift Container Platform assigns an additional virtual IP address to the service. The IP address can be outside the service network defined for the cluster. A service configured with an ExternalIP functions similarly to a service with type=NodePort, allowing you to direct traffic to a local node for load balancing.

You must configure your networking infrastructure to ensure that the external IP address blocks that you define are routed to the cluster.

OpenShift Container Platform extends the ExternalIP functionality in Kubernetes by adding the following capabilities:

  • Restrictions on the use of external IP addresses by users through a configurable policy
  • Allocation of an external IP address automatically to a service upon request
Warning

Disabled by default, use of ExternalIP functionality can be a security risk, because in-cluster traffic to an external IP address is directed to that service. This could allow cluster users to intercept sensitive traffic destined for external resources.

Important

This feature is supported only in non-cloud deployments. For cloud deployments, use the load balancer services for automatic deployment of a cloud load balancer to target the endpoints of a service.

You can assign an external IP address in the following ways:

Automatic assignment of an external IP
OpenShift Container Platform automatically assigns an IP address from the autoAssignCIDRs CIDR block to the spec.externalIPs[] array when you create a Service object with spec.type=LoadBalancer set. In this case, OpenShift Container Platform implements a non-cloud version of the load balancer service type and assigns IP addresses to the services. Automatic assignment is disabled by default and must be configured by a cluster administrator as described in the following section.
Manual assignment of an external IP
OpenShift Container Platform uses the IP addresses assigned to the spec.externalIPs[] array when you create a Service object. You cannot specify an IP address that is already in use by another service.

16.2.2.1. Configuration for ExternalIP

Use of an external IP address in OpenShift Container Platform is governed by the following fields in the Network.config.openshift.io CR named cluster:

  • spec.externalIP.autoAssignCIDRs defines an IP address block used by the load balancer when choosing an external IP address for the service. OpenShift Container Platform supports only a single IP address block for automatic assignment. This can be simpler than having to manage the port space of a limited number of shared IP addresses when manually assigning ExternalIPs to services. If automatic assignment is enabled, a Service object with spec.type=LoadBalancer is allocated an external IP address.
  • spec.externalIP.policy defines the permissible IP address blocks when manually specifying an IP address. OpenShift Container Platform does not apply policy rules to IP address blocks defined by spec.externalIP.autoAssignCIDRs.

If routed correctly, external traffic from the configured external IP address block can reach service endpoints through any TCP or UDP port that the service exposes.

Important

You must ensure that the IP address block you assign terminates at one or more nodes in your cluster.

OpenShift Container Platform supports both the automatic and manual assignment of IP addresses, and each address is guaranteed to be assigned to a maximum of one service. This ensures that each service can expose its chosen ports regardless of the ports exposed by other services.

Note

To use IP address blocks defined by autoAssignCIDRs in OpenShift Container Platform, you must configure the necessary IP address assignment and routing for your host network.

The following YAML describes a service with an external IP address configured:

Example Service object with spec.externalIPs[] set

apiVersion: v1
kind: Service
metadata:
  name: http-service
spec:
  clusterIP: 172.30.163.110
  externalIPs:
  - 192.168.132.253
  externalTrafficPolicy: Cluster
  ports:
  - name: highport
    nodePort: 31903
    port: 30102
    protocol: TCP
    targetPort: 30102
  selector:
    app: web
  sessionAffinity: None
  type: LoadBalancer
status:
  loadBalancer:
    ingress:
    - ip: 192.168.132.253

16.2.2.2. Restrictions on the assignment of an external IP address

As a cluster administrator, you can specify IP address blocks to allow and to reject.

Restrictions apply only to users without cluster-admin privileges. A cluster administrator can always set the service spec.externalIPs[] field to any IP address.

You configure IP address policy with a policy object defined by specifying the spec.ExternalIP.policy field. The policy object has the following shape:

{
  "policy": {
    "allowedCIDRs": [],
    "rejectedCIDRs": []
  }
}

When configuring policy restrictions, the following rules apply:

  • If policy={} is set, then creating a Service object with spec.ExternalIPs[] set will fail. This is the default for OpenShift Container Platform. The behavior when policy=null is set is identical.
  • If policy is set and either policy.allowedCIDRs[] or policy.rejectedCIDRs[] is set, the following rules apply:

    • If allowedCIDRs[] and rejectedCIDRs[] are both set, then rejectedCIDRs[] has precedence over allowedCIDRs[].
    • If allowedCIDRs[] is set, creating a Service object with spec.ExternalIPs[] will succeed only if the specified IP addresses are allowed.
    • If rejectedCIDRs[] is set, creating a Service object with spec.ExternalIPs[] will succeed only if the specified IP addresses are not rejected.

16.2.2.3. Example policy objects

The examples that follow demonstrate several different policy configurations.

  • In the following example, the policy prevents OpenShift Container Platform from creating any service with an external IP address specified:

    Example policy to reject any value specified for Service object spec.externalIPs[]

    apiVersion: config.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      externalIP:
        policy: {}
      ...

  • In the following example, both the allowedCIDRs and rejectedCIDRs fields are set.

    Example policy that includes both allowed and rejected CIDR blocks

    apiVersion: config.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      externalIP:
        policy:
          allowedCIDRs:
          - 172.16.66.10/23
          rejectedCIDRs:
          - 172.16.66.10/24
      ...

  • In the following example, policy is set to null. If set to null, when inspecting the configuration object by entering oc get networks.config.openshift.io -o yaml, the policy field will not appear in the output.

    Example policy to allow any value specified for Service object spec.externalIPs[]

    apiVersion: config.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      externalIP:
        policy: null
      ...

16.2.3. ExternalIP address block configuration

The configuration for ExternalIP address blocks is defined by a Network custom resource (CR) named cluster. The Network CR is part of the config.openshift.io API group.

Important

During cluster installation, the Cluster Version Operator (CVO) automatically creates a Network CR named cluster. Creating any other CR objects of this type is not supported.

The following YAML describes the ExternalIP configuration:

Network.config.openshift.io CR named cluster

apiVersion: config.openshift.io/v1
kind: Network
metadata:
  name: cluster
spec:
  externalIP:
    autoAssignCIDRs: [] 1
    policy: 2
      ...

1
Defines the IP address block in CIDR format that is available for automatic assignment of external IP addresses to a service. Only a single IP address range is allowed.
2
Defines restrictions on manual assignment of an IP address to a service. If no restrictions are defined, specifying the spec.externalIP field in a Service object is not allowed. By default, no restrictions are defined.

The following YAML describes the fields for the policy stanza:

Network.config.openshift.io policy stanza

policy:
  allowedCIDRs: [] 1
  rejectedCIDRs: [] 2

1
A list of allowed IP address ranges in CIDR format.
2
A list of rejected IP address ranges in CIDR format.
Example external IP configurations

Several possible configurations for external IP address pools are displayed in the following examples:

  • The following YAML describes a configuration that enables automatically assigned external IP addresses:

    Example configuration with spec.externalIP.autoAssignCIDRs set

    apiVersion: config.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      ...
      externalIP:
        autoAssignCIDRs:
        - 192.168.132.254/29

  • The following YAML configures policy rules for the allowed and rejected CIDR ranges:

    Example configuration with spec.externalIP.policy set

    apiVersion: config.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      ...
      externalIP:
        policy:
          allowedCIDRs:
          - 192.168.132.0/29
          - 192.168.132.8/29
          rejectedCIDRs:
          - 192.168.132.7/32

16.2.4. Configure external IP address blocks for your cluster

As a cluster administrator, you can configure the following ExternalIP settings:

  • An ExternalIP address block used by OpenShift Container Platform to automatically populate the spec.clusterIP field for a Service object.
  • A policy object to restrict what IP addresses may be manually assigned to the spec.clusterIP array of a Service object.

Prerequisites

  • Install the OpenShift CLI (oc).
  • Access to the cluster as a user with the cluster-admin role.

Procedure

  1. Optional: To display the current external IP configuration, enter the following command:

    $ oc describe networks.config cluster
  2. To edit the configuration, enter the following command:

    $ oc edit networks.config cluster
  3. Modify the ExternalIP configuration, as in the following example:

    apiVersion: config.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      ...
      externalIP: 1
      ...
    1
    Specify the configuration for the externalIP stanza.
  4. To confirm the updated ExternalIP configuration, enter the following command:

    $ oc get networks.config cluster -o go-template='{{.spec.externalIP}}{{"\n"}}'

16.2.5. Next steps

16.3. Configuring ingress cluster traffic using an Ingress Controller

OpenShift Container Platform provides methods for communicating from outside the cluster with services running in the cluster. This method uses an Ingress Controller.

16.3.1. Using Ingress Controllers and routes

The Ingress Operator manages Ingress Controllers and wildcard DNS.

Using an Ingress Controller is the most common way to allow external access to an OpenShift Container Platform cluster.

An Ingress Controller is configured to accept external requests and proxy them based on the configured routes. This is limited to HTTP, HTTPS using SNI, and TLS using SNI, which is sufficient for web applications and services that work over TLS with SNI.

Work with your administrator to configure an Ingress Controller to accept external requests and proxy them based on the configured routes.

The administrator can create a wildcard DNS entry and then set up an Ingress Controller. Then, you can work with the edge Ingress Controller without having to contact the administrators.

By default, every ingress controller in the cluster can admit any route created in any project in the cluster.

The Ingress Controller:

  • Has two replicas by default, which means it should be running on two worker nodes.
  • Can be scaled up to have more replicas on more nodes.
Note

The procedures in this section require prerequisites performed by the cluster administrator.

16.3.2. Prerequisites

Before starting the following procedures, the administrator must:

  • Set up the external port to the cluster networking environment so that requests can reach the cluster.
  • Make sure there is at least one user with cluster admin role. To add this role to a user, run the following command:

    $ oc adm policy add-cluster-role-to-user cluster-admin username
  • Have an OpenShift Container Platform cluster with at least one master and at least one node and a system outside the cluster that has network access to the cluster. This procedure assumes that the external system is on the same subnet as the cluster. The additional networking required for external systems on a different subnet is out-of-scope for this topic.

16.3.3. Creating a project and service

If the project and service that you want to expose do not exist, first create the project, then the service.

If the project and service already exist, skip to the procedure on exposing the service to create a route.

Prerequisites

  • Install the oc CLI and log in as a cluster administrator.

Procedure

  1. Create a new project for your service by running the oc new-project command:

    $ oc new-project myproject
  2. Use the oc new-app command to create your service:

    $ oc new-app nodejs:12~https://github.com/sclorg/nodejs-ex.git
  3. To verify that the service was created, run the following command:

    $ oc get svc -n myproject

    Example output

    NAME        TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
    nodejs-ex   ClusterIP   172.30.197.157   <none>        8080/TCP   70s

    By default, the new service does not have an external IP address.

16.3.4. Exposing the service by creating a route

You can expose the service as a route by using the oc expose command.

Procedure

To expose the service:

  1. Log in to OpenShift Container Platform.
  2. Log in to the project where the service you want to expose is located:

    $ oc project myproject
  3. Run the oc expose service command to expose the route:

    $ oc expose service nodejs-ex

    Example output

    route.route.openshift.io/nodejs-ex exposed

  4. To verify that the service is exposed, you can use a tool, such as cURL, to make sure the service is accessible from outside the cluster.

    1. Use the oc get route command to find the route’s host name:

      $ oc get route

      Example output

      NAME        HOST/PORT                        PATH   SERVICES    PORT       TERMINATION   WILDCARD
      nodejs-ex   nodejs-ex-myproject.example.com         nodejs-ex   8080-tcp                 None

    2. Use cURL to check that the host responds to a GET request:

      $ curl --head nodejs-ex-myproject.example.com

      Example output

      HTTP/1.1 200 OK
      ...

16.3.5. Configuring Ingress Controller sharding by using route labels

Ingress Controller sharding by using route labels means that the Ingress Controller serves any route in any namespace that is selected by the route selector.

Ingress Controller sharding is useful when balancing incoming traffic load among a set of Ingress Controllers and when isolating traffic to a specific Ingress Controller. For example, company A goes to one Ingress Controller and company B to another.

Procedure

  1. Edit the router-internal.yaml file:

    # cat router-internal.yaml
    apiVersion: v1
    items:
    - apiVersion: operator.openshift.io/v1
      kind: IngressController
      metadata:
        name: sharded
        namespace: openshift-ingress-operator
      spec:
        domain: <apps-sharded.basedomain.example.net>
        nodePlacement:
          nodeSelector:
            matchLabels:
              node-role.kubernetes.io/worker: ""
        routeSelector:
          matchLabels:
            type: sharded
      status: {}
    kind: List
    metadata:
      resourceVersion: ""
      selfLink: ""
  2. Apply the Ingress Controller router-internal.yaml file:

    # oc apply -f router-internal.yaml

    The Ingress Controller selects routes in any namespace that have the label type: sharded.

16.3.6. Configuring Ingress Controller sharding by using namespace labels

Ingress Controller sharding by using namespace labels means that the Ingress Controller serves any route in any namespace that is selected by the namespace selector.

Ingress Controller sharding is useful when balancing incoming traffic load among a set of Ingress Controllers and when isolating traffic to a specific Ingress Controller. For example, company A goes to one Ingress Controller and company B to another.

Warning

If you deploy the Keepalived Ingress VIP, do not deploy a non-default Ingress Controller with value HostNetwork for the endpointPublishingStrategy parameter. Doing so might cause issues. Use value NodePort instead of HostNetwork for endpointPublishingStrategy.

Procedure

  1. Edit the router-internal.yaml file:

    # cat router-internal.yaml

    Example output

    apiVersion: v1
    items:
    - apiVersion: operator.openshift.io/v1
      kind: IngressController
      metadata:
        name: sharded
        namespace: openshift-ingress-operator
      spec:
        domain: <apps-sharded.basedomain.example.net>
        nodePlacement:
          nodeSelector:
            matchLabels:
              node-role.kubernetes.io/worker: ""
        namespaceSelector:
          matchLabels:
            type: sharded
      status: {}
    kind: List
    metadata:
      resourceVersion: ""
      selfLink: ""

  2. Apply the Ingress Controller router-internal.yaml file:

    # oc apply -f router-internal.yaml

    The Ingress Controller selects routes in any namespace that is selected by the namespace selector that have the label type: sharded.

16.3.7. Additional resources

16.4. Configuring ingress cluster traffic using a load balancer

OpenShift Container Platform provides methods for communicating from outside the cluster with services running in the cluster. This method uses a load balancer.

16.4.1. Using a load balancer to get traffic into the cluster

If you do not need a specific external IP address, you can configure a load balancer service to allow external access to an OpenShift Container Platform cluster.

A load balancer service allocates a unique IP. The load balancer has a single edge router IP, which can be a virtual IP (VIP), but is still a single machine for initial load balancing.

Note

If a pool is configured, it is done at the infrastructure level, not by a cluster administrator.

Note

The procedures in this section require prerequisites performed by the cluster administrator.

16.4.2. Prerequisites

Before starting the following procedures, the administrator must:

  • Set up the external port to the cluster networking environment so that requests can reach the cluster.
  • Make sure there is at least one user with cluster admin role. To add this role to a user, run the following command:

    $ oc adm policy add-cluster-role-to-user cluster-admin username
  • Have an OpenShift Container Platform cluster with at least one master and at least one node and a system outside the cluster that has network access to the cluster. This procedure assumes that the external system is on the same subnet as the cluster. The additional networking required for external systems on a different subnet is out-of-scope for this topic.

16.4.3. Creating a project and service

If the project and service that you want to expose do not exist, first create the project, then the service.

If the project and service already exist, skip to the procedure on exposing the service to create a route.

Prerequisites

  • Install the oc CLI and log in as a cluster administrator.

Procedure

  1. Create a new project for your service by running the oc new-project command:

    $ oc new-project myproject
  2. Use the oc new-app command to create your service:

    $ oc new-app nodejs:12~https://github.com/sclorg/nodejs-ex.git
  3. To verify that the service was created, run the following command:

    $ oc get svc -n myproject

    Example output

    NAME        TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
    nodejs-ex   ClusterIP   172.30.197.157   <none>        8080/TCP   70s

    By default, the new service does not have an external IP address.

16.4.4. Exposing the service by creating a route

You can expose the service as a route by using the oc expose command.

Procedure

To expose the service:

  1. Log in to OpenShift Container Platform.
  2. Log in to the project where the service you want to expose is located:

    $ oc project myproject
  3. Run the oc expose service command to expose the route:

    $ oc expose service nodejs-ex

    Example output

    route.route.openshift.io/nodejs-ex exposed

  4. To verify that the service is exposed, you can use a tool, such as cURL, to make sure the service is accessible from outside the cluster.

    1. Use the oc get route command to find the route’s host name:

      $ oc get route

      Example output

      NAME        HOST/PORT                        PATH   SERVICES    PORT       TERMINATION   WILDCARD
      nodejs-ex   nodejs-ex-myproject.example.com         nodejs-ex   8080-tcp                 None

    2. Use cURL to check that the host responds to a GET request:

      $ curl --head nodejs-ex-myproject.example.com

      Example output

      HTTP/1.1 200 OK
      ...

16.4.5. Creating a load balancer service

Use the following procedure to create a load balancer service.

Prerequisites

  • Make sure that the project and service you want to expose exist.

Procedure

To create a load balancer service:

  1. Log in to OpenShift Container Platform.
  2. Load the project where the service you want to expose is located.

    $ oc project project1
  3. Open a text file on the control plane node (also known as the master node) and paste the following text, editing the file as needed:

    Sample load balancer configuration file

    apiVersion: v1
    kind: Service
    metadata:
      name: egress-2 1
    spec:
      ports:
      - name: db
        port: 3306 2
      loadBalancerIP:
      loadBalancerSourceRanges: 3
      - 10.0.0.0/8
      - 192.168.0.0/16
      type: LoadBalancer 4
      selector:
        name: mysql 5

    1
    Enter a descriptive name for the load balancer service.
    2
    Enter the same port that the service you want to expose is listening on.
    3
    Enter a list of specific IP addresses to restrict traffic through the load balancer. This field is ignored if the cloud-provider does not support the feature.
    4
    Enter Loadbalancer as the type.
    5
    Enter the name of the service.
    Note

    To restrict traffic through the load balancer to specific IP addresses, it is recommended to use the service.beta.kubernetes.io/load-balancer-source-ranges annotation rather than setting the loadBalancerSourceRanges field. With the annotation, you can more easily migrate to the OpenShift API, which will be implemented in a future release.

  4. Save and exit the file.
  5. Run the following command to create the service:

    $ oc create -f <file-name>

    For example:

    $ oc create -f mysql-lb.yaml
  6. Execute the following command to view the new service:

    $ oc get svc

    Example output

    NAME       TYPE           CLUSTER-IP      EXTERNAL-IP                             PORT(S)          AGE
    egress-2   LoadBalancer   172.30.22.226   ad42f5d8b303045-487804948.example.com   3306:30357/TCP   15m

    The service has an external IP address automatically assigned if there is a cloud provider enabled.

  7. On the master, use a tool, such as cURL, to make sure you can reach the service using the public IP address:

    $ curl <public-ip>:<port>

    For example:

    $ curl 172.29.121.74:3306

    The examples in this section use a MySQL service, which requires a client application. If you get a string of characters with the Got packets out of order message, you are connecting with the service:

    If you have a MySQL client, log in with the standard CLI command:

    $ mysql -h 172.30.131.89 -u admin -p

    Example output

    Enter password:
    Welcome to the MariaDB monitor.  Commands end with ; or \g.
    
    MySQL [(none)]>

16.5. Configuring ingress cluster traffic on AWS using a Network Load Balancer

OpenShift Container Platform provides methods for communicating from outside the cluster with services running in the cluster. This method uses a Network Load Balancer (NLB), which forwards the client’s IP address to the node. You can configure an NLB on a new or existing AWS cluster.

16.5.1. Replacing Ingress Controller Classic Load Balancer with Network Load Balancer

You can replace an Ingress Controller that is using a Classic Load Balancer (CLB) with one that uses a Network Load Balancer (NLB) on AWS.

Warning

This procedure causes an expected outage that can last several minutes due to new DNS records propagation, new load balancers provisioning, and other factors. IP addresses and canonical names of the Ingress Controller load balancer might change after applying this procedure.

Procedure

  1. Create a file with a new default Ingress Controller. The following example assumes that your default Ingress Controller has an External scope and no other customizations:

    Example ingresscontroller.yml file

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      creationTimestamp: null
      name: default
      namespace: openshift-ingress-operator
    spec:
      endpointPublishingStrategy:
        loadBalancer:
          scope: External
          providerParameters:
            type: AWS
            aws:
              type: NLB
        type: LoadBalancerService

    If your default Ingress Controller has other customizations, ensure that you modify the file accordingly.

  2. Force replace the Ingress Controller YAML file:

    $ oc replace --force --wait -f ingresscontroller.yml

    Wait until the Ingress Controller is replaced. Expect serveral of minutes of outages.

16.5.2. Configuring an Ingress Controller Network Load Balancer on an existing AWS cluster

You can create an Ingress Controller backed by an AWS Network Load Balancer (NLB) on an existing cluster.

Prerequisites

  • You must have an installed AWS cluster.
  • PlatformStatus of the infrastructure resource must be AWS.

    • To verify that the PlatformStatus is AWS, run:

      $ oc get infrastructure/cluster -o jsonpath='{.status.platformStatus.type}'
      AWS

Procedure

Create an Ingress Controller backed by an AWS NLB on an existing cluster.

  1. Create the Ingress Controller manifest:

     $ cat ingresscontroller-aws-nlb.yaml

    Example output

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      name: $my_ingress_controller1
      namespace: openshift-ingress-operator
    spec:
      domain: $my_unique_ingress_domain2
      endpointPublishingStrategy:
        type: LoadBalancerService
        loadBalancer:
          scope: External3
          providerParameters:
            type: AWS
            aws:
              type: NLB

    1
    Replace $my_ingress_controller with a unique name for the Ingress Controller.
    2
    Replace $my_unique_ingress_domain with a domain name that is unique among all Ingress Controllers in the cluster.
    3
    You can replace External with Internal to use an internal NLB.
  2. Create the resource in the cluster:

    $ oc create -f ingresscontroller-aws-nlb.yaml
Important

Before you can configure an Ingress Controller NLB on a new AWS cluster, you must complete the Creating the installation configuration file procedure.

16.5.3. Configuring an Ingress Controller Network Load Balancer on a new AWS cluster

You can create an Ingress Controller backed by an AWS Network Load Balancer (NLB) on a new cluster.

Prerequisites

  • Create the install-config.yaml file and complete any modifications to it.

Procedure

Create an Ingress Controller backed by an AWS NLB on a new cluster.

  1. Change to the directory that contains the installation program and create the manifests:

    $ ./openshift-install create manifests --dir <installation_directory> 1
    1
    For <installation_directory>, specify the name of the directory that contains the install-config.yaml file for your cluster.
  2. Create a file that is named cluster-ingress-default-ingresscontroller.yaml in the <installation_directory>/manifests/ directory:

    $ touch <installation_directory>/manifests/cluster-ingress-default-ingresscontroller.yaml 1
    1
    For <installation_directory>, specify the directory name that contains the manifests/ directory for your cluster.

    After creating the file, several network configuration files are in the manifests/ directory, as shown:

    $ ls <installation_directory>/manifests/cluster-ingress-default-ingresscontroller.yaml

    Example output

    cluster-ingress-default-ingresscontroller.yaml

  3. Open the cluster-ingress-default-ingresscontroller.yaml file in an editor and enter a CR that describes the Operator configuration you want:

    apiVersion: operator.openshift.io/v1
    kind: IngressController
    metadata:
      creationTimestamp: null
      name: default
      namespace: openshift-ingress-operator
    spec:
      endpointPublishingStrategy:
        loadBalancer:
          scope: External
          providerParameters:
            type: AWS
            aws:
              type: NLB
        type: LoadBalancerService
  4. Save the cluster-ingress-default-ingresscontroller.yaml file and quit the text editor.
  5. Optional: Back up the manifests/cluster-ingress-default-ingresscontroller.yaml file. The installation program deletes the manifests/ directory when creating the cluster.

16.5.4. Additional resources

16.6. Configuring ingress cluster traffic for a service external IP

You can attach an external IP address to a service so that it is available to traffic outside the cluster. This is generally useful only for a cluster installed on bare metal hardware. The external network infrastructure must be configured correctly to route traffic to the service.

16.6.1. Prerequisites

16.6.2. Attaching an ExternalIP to a service

You can attach an ExternalIP to a service. If your cluster is configured to allocate an ExternalIP automatically, you might not need to manually attach an ExternalIP to the service.

Procedure

  1. Optional: To confirm what IP address ranges are configured for use with ExternalIP, enter the following command:

    $ oc get networks.config cluster -o jsonpath='{.spec.externalIP}{"\n"}'

    If autoAssignCIDRs is set, OpenShift Container Platform automatically assigns an ExternalIP to a new Service object if the spec.externalIPs field is not specified.

  2. Attach an ExternalIP to the service.

    1. If you are creating a new service, specify the spec.externalIPs field and provide an array of one or more valid IP addresses. For example:

      apiVersion: v1
      kind: Service
      metadata:
        name: svc-with-externalip
      spec:
        ...
        externalIPs:
        - 192.174.120.10
    2. If you are attaching an ExternalIP to an existing service, enter the following command. Replace <name> with the service name. Replace <ip_address> with a valid ExternalIP address. You can provide multiple IP addresses separated by commas.

      $ oc patch svc <name> -p \
        '{
          "spec": {
            "externalIPs": [ "<ip_address>" ]
          }
        }'

      For example:

      $ oc patch svc mysql-55-rhel7 -p '{"spec":{"externalIPs":["192.174.120.10"]}}'

      Example output

      "mysql-55-rhel7" patched

  3. To confirm that an ExternalIP address is attached to the service, enter the following command. If you specified an ExternalIP for a new service, you must create the service first.

    $ oc get svc

    Example output

    NAME               CLUSTER-IP      EXTERNAL-IP     PORT(S)    AGE
    mysql-55-rhel7     172.30.131.89   192.174.120.10  3306/TCP   13m

16.6.3. Additional resources

16.7. Configuring ingress cluster traffic using a NodePort

OpenShift Container Platform provides methods for communicating from outside the cluster with services running in the cluster. This method uses a NodePort.

16.7.1. Using a NodePort to get traffic into the cluster

Use a NodePort-type Service resource to expose a service on a specific port on all nodes in the cluster. The port is specified in the Service resource’s .spec.ports[*].nodePort field.

Important

Using a node port requires additional port resources.

A NodePort exposes the service on a static port on the node’s IP address. NodePorts are in the 30000 to 32767 range by default, which means a NodePort is unlikely to match a service’s intended port. For example, port 8080 may be exposed as port 31020 on the node.

The administrator must ensure the external IP addresses are routed to the nodes.

NodePorts and external IPs are independent and both can be used concurrently.

Note

The procedures in this section require prerequisites performed by the cluster administrator.

16.7.2. Prerequisites

Before starting the following procedures, the administrator must:

  • Set up the external port to the cluster networking environment so that requests can reach the cluster.
  • Make sure there is at least one user with cluster admin role. To add this role to a user, run the following command:

    $ oc adm policy add-cluster-role-to-user cluster-admin <user_name>
  • Have an OpenShift Container Platform cluster with at least one master and at least one node and a system outside the cluster that has network access to the cluster. This procedure assumes that the external system is on the same subnet as the cluster. The additional networking required for external systems on a different subnet is out-of-scope for this topic.

16.7.3. Creating a project and service

If the project and service that you want to expose do not exist, first create the project, then the service.

If the project and service already exist, skip to the procedure on exposing the service to create a route.

Prerequisites

  • Install the oc CLI and log in as a cluster administrator.

Procedure

  1. Create a new project for your service by running the oc new-project command:

    $ oc new-project myproject
  2. Use the oc new-app command to create your service:

    $ oc new-app nodejs:12~https://github.com/sclorg/nodejs-ex.git
  3. To verify that the service was created, run the following command:

    $ oc get svc -n myproject

    Example output

    NAME        TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
    nodejs-ex   ClusterIP   172.30.197.157   <none>        8080/TCP   70s

    By default, the new service does not have an external IP address.

16.7.4. Exposing the service by creating a route

You can expose the service as a route by using the oc expose command.

Procedure

To expose the service:

  1. Log in to OpenShift Container Platform.
  2. Log in to the project where the service you want to expose is located:

    $ oc project myproject
  3. To expose a node port for the application, enter the following command. OpenShift Container Platform automatically selects an available port in the 30000-32767 range.

    $ oc expose service nodejs-ex  --type=NodePort --name=nodejs-ex-nodeport --generator="service/v2"

    Example output

    service/nodejs-ex-nodeport exposed

  4. Optional: To confirm the service is available with a node port exposed, enter the following command:

    $ oc get svc -n myproject

    Example output

    NAME                TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
    nodejs-ex           ClusterIP   172.30.217.127   <none>        3306/TCP         9m44s
    nodejs-ex-ingress   NodePort    172.30.107.72    <none>        3306:31345/TCP   39s

  5. Optional: To remove the service created automatically by the oc new-app command, enter the following command:

    $ oc delete svc nodejs-ex

16.7.5. Additional resources

Chapter 17. Configuring the cluster-wide proxy

Production environments can deny direct access to the Internet and instead have an HTTP or HTTPS proxy available. You can configure OpenShift Container Platform to use a proxy by modifying the Proxy object for existing clusters or by configuring the proxy settings in the install-config.yaml file for new clusters.

17.1. Prerequisites

  • Review the sites that your cluster requires access to and determine whether any of them must bypass the proxy. By default, all cluster system egress traffic is proxied, including calls to the cloud provider API for the cloud that hosts your cluster. System-wide proxy affects system components only, not user workloads. Add sites to the Proxy object’s spec.noProxy field to bypass the proxy if necessary.

    Note

    The Proxy object status.noProxy field is populated with the values of the networking.machineNetwork[].cidr, networking.clusterNetwork[].cidr, and networking.serviceNetwork[] fields from your installation configuration.

    For installations on Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, and Red Hat OpenStack Platform (RHOSP), the Proxy object status.noProxy field is also populated with the instance metadata endpoint (169.254.169.254).

17.2. Enabling the cluster-wide proxy

The Proxy object is used to manage the cluster-wide egress proxy. When a cluster is installed or upgraded without the proxy configured, a Proxy object is still generated but it will have a nil spec. For example:

apiVersion: config.openshift.io/v1
kind: Proxy
metadata:
  name: cluster
spec:
  trustedCA:
    name: ""
status:

A cluster administrator can configure the proxy for OpenShift Container Platform by modifying this cluster Proxy object.

Note

Only the Proxy object named cluster is supported, and no additional proxies can be created.

Prerequisites

  • Cluster administrator permissions
  • OpenShift Container Platform oc CLI tool installed

Procedure

  1. Create a ConfigMap that contains any additional CA certificates required for proxying HTTPS connections.

    Note

    You can skip this step if the proxy’s identity certificate is signed by an authority from the RHCOS trust bundle.

    1. Create a file called user-ca-bundle.yaml with the following contents, and provide the values of your PEM-encoded certificates:

      apiVersion: v1
      data:
        ca-bundle.crt: | 1
          <MY_PEM_ENCODED_CERTS> 2
      kind: ConfigMap
      metadata:
        name: user-ca-bundle 3
        namespace: openshift-config 4
      1
      This data key must be named ca-bundle.crt.
      2
      One or more PEM-encoded X.509 certificates used to sign the proxy’s identity certificate.
      3
      The ConfigMap name that will be referenced from the Proxy object.
      4
      The ConfigMap must be in the openshift-config namespace.
    2. Create the ConfigMap from this file:

      $ oc create -f user-ca-bundle.yaml
  2. Use the oc edit command to modify the Proxy object:

    $ oc edit proxy/cluster
  3. Configure the necessary fields for the proxy:

    apiVersion: config.openshift.io/v1
    kind: Proxy
    metadata:
      name: cluster
    spec:
      httpProxy: http://<username>:<pswd>@<ip>:<port> 1
      httpsProxy: http://<username>:<pswd>@<ip>:<port> 2
      noProxy: example.com 3
      readinessEndpoints:
      - http://www.google.com 4
      - https://www.google.com
      trustedCA:
        name: user-ca-bundle 5
    1
    A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
    2
    A proxy URL to use for creating HTTPS connections outside the cluster.
    3
    A comma-separated list of destination domain names, domains, IP addresses or other network CIDRs to exclude proxying.

    Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass proxy for all destinations. If you scale up workers that are not included in the network defined by the networking.machineNetwork[].cidr field from the installation configuration, you must add them to this list to prevent connection issues.

    This field is ignored if neither the httpProxy or httpsProxy fields are set.

    4
    One or more URLs external to the cluster to use to perform a readiness check before writing the httpProxy and httpsProxy values to status.
    5
    A reference to the ConfigMap in the openshift-config namespace that contains additional CA certificates required for proxying HTTPS connections. Note that the ConfigMap must already exist before referencing it here. This field is required unless the proxy’s identity certificate is signed by an authority from the RHCOS trust bundle.
  4. Save the file to apply the changes.

17.3. Removing the cluster-wide proxy

The cluster Proxy object cannot be deleted. To remove the proxy from a cluster, remove all spec fields from the Proxy object.

Prerequisites

  • Cluster administrator permissions
  • OpenShift Container Platform oc CLI tool installed

Procedure

  1. Use the oc edit command to modify the proxy:

    $ oc edit proxy/cluster
  2. Remove all spec fields from the Proxy object. For example:

    apiVersion: config.openshift.io/v1
    kind: Proxy
    metadata:
      name: cluster
    spec: {}
    status: {}
  3. Save the file to apply the changes.

Additional resources

Chapter 18. Configuring a custom PKI

Some platform components, such as the web console, use Routes for communication and must trust other components' certificates to interact with them. If you are using a custom public key infrastructure (PKI), you must configure it so its privately signed CA certificates are recognized across the cluster.

You can leverage the Proxy API to add cluster-wide trusted CA certificates. You must do this either during installation or at runtime.

  • During installation, configure the cluster-wide proxy. You must define your privately signed CA certificates in the install-config.yaml file’s additionalTrustBundle setting.

    The installation program generates a ConfigMap that is named user-ca-bundle that contains the additional CA certificates you defined. The Cluster Network Operator then creates a trusted-ca-bundle ConfigMap that merges these CA certificates with the Red Hat Enterprise Linux CoreOS (RHCOS) trust bundle; this ConfigMap is referenced in the Proxy object’s trustedCA field.

  • At runtime, modify the default Proxy object to include your privately signed CA certificates (part of cluster’s proxy enablement workflow). This involves creating a ConfigMap that contains the privately signed CA certificates that should be trusted by the cluster, and then modifying the proxy resource with the trustedCA referencing the privately signed certificates' ConfigMap.
Note

The installer configuration’s additionalTrustBundle field and the proxy resource’s trustedCA field are used to manage the cluster-wide trust bundle; additionalTrustBundle is used at install time and the proxy’s trustedCA is used at runtime.

The trustedCA field is a reference to a ConfigMap containing the custom certificate and key pair used by the cluster component.

18.1. Configuring the cluster-wide proxy during installation

Production environments can deny direct access to the Internet and instead have an HTTP or HTTPS proxy available. You can configure a new OpenShift Container Platform cluster to use a proxy by configuring the proxy settings in the install-config.yaml file.

Prerequisites

  • You have an existing install-config.yaml file.
  • You reviewed the sites that your cluster requires access to and determined whether any of them need to bypass the proxy. By default, all cluster egress traffic is proxied, including calls to hosting cloud provider APIs. You added sites to the Proxy object’s spec.noProxy field to bypass the proxy if necessary.

    Note

    The Proxy object status.noProxy field is populated with the values of the networking.machineNetwork[].cidr, networking.clusterNetwork[].cidr, and networking.serviceNetwork[] fields from your installation configuration.

    For installations on Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, and Red Hat OpenStack Platform (RHOSP), the Proxy object status.noProxy field is also populated with the instance metadata endpoint (169.254.169.254).

Procedure

  1. Edit your install-config.yaml file and add the proxy settings. For example:

    apiVersion: v1
    baseDomain: my.domain.com
    proxy:
      httpProxy: http://<username>:<pswd>@<ip>:<port> 1
      httpsProxy: https://<username>:<pswd>@<ip>:<port> 2
      noProxy: example.com 3
    additionalTrustBundle: | 4
        -----BEGIN CERTIFICATE-----
        <MY_TRUSTED_CA_CERT>
        -----END CERTIFICATE-----
    ...
    1
    A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
    2
    A proxy URL to use for creating HTTPS connections outside the cluster.
    3
    A comma-separated list of destination domain names, IP addresses, or other network CIDRs to exclude from proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass the proxy for all destinations.
    4
    If provided, the installation program generates a config map that is named user-ca-bundle in the openshift-config namespace to hold the additional CA certificates. If you provide additionalTrustBundle and at least one proxy setting, the Proxy object is configured to reference the user-ca-bundle config map in the trustedCA field. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges the contents specified for the trustedCA parameter with the RHCOS trust bundle. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the RHCOS trust bundle.
    Note

    The installation program does not support the proxy readinessEndpoints field.

  2. Save the file and reference it when installing OpenShift Container Platform.

The installation program creates a cluster-wide proxy that is named cluster that uses the proxy settings in the provided install-config.yaml file. If no proxy settings are provided, a cluster Proxy object is still created, but it will have a nil spec.

Note

Only the Proxy object named cluster is supported, and no additional proxies can be created.

18.2. Enabling the cluster-wide proxy

The Proxy object is used to manage the cluster-wide egress proxy. When a cluster is installed or upgraded without the proxy configured, a Proxy object is still generated but it will have a nil spec. For example:

apiVersion: config.openshift.io/v1
kind: Proxy
metadata:
  name: cluster
spec:
  trustedCA:
    name: ""
status:

A cluster administrator can configure the proxy for OpenShift Container Platform by modifying this cluster Proxy object.

Note

Only the Proxy object named cluster is supported, and no additional proxies can be created.

Prerequisites

  • Cluster administrator permissions
  • OpenShift Container Platform oc CLI tool installed

Procedure

  1. Create a ConfigMap that contains any additional CA certificates required for proxying HTTPS connections.

    Note

    You can skip this step if the proxy’s identity certificate is signed by an authority from the RHCOS trust bundle.

    1. Create a file called user-ca-bundle.yaml with the following contents, and provide the values of your PEM-encoded certificates:

      apiVersion: v1
      data:
        ca-bundle.crt: | 1
          <MY_PEM_ENCODED_CERTS> 2
      kind: ConfigMap
      metadata:
        name: user-ca-bundle 3
        namespace: openshift-config 4
      1
      This data key must be named ca-bundle.crt.
      2
      One or more PEM-encoded X.509 certificates used to sign the proxy’s identity certificate.
      3
      The ConfigMap name that will be referenced from the Proxy object.
      4
      The ConfigMap must be in the openshift-config namespace.
    2. Create the ConfigMap from this file:

      $ oc create -f user-ca-bundle.yaml
  2. Use the oc edit command to modify the Proxy object:

    $ oc edit proxy/cluster
  3. Configure the necessary fields for the proxy:

    apiVersion: config.openshift.io/v1
    kind: Proxy
    metadata:
      name: cluster
    spec:
      httpProxy: http://<username>:<pswd>@<ip>:<port> 1
      httpsProxy: http://<username>:<pswd>@<ip>:<port> 2
      noProxy: example.com 3
      readinessEndpoints:
      - http://www.google.com 4
      - https://www.google.com
      trustedCA:
        name: user-ca-bundle 5
    1
    A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
    2
    A proxy URL to use for creating HTTPS connections outside the cluster.
    3
    A comma-separated list of destination domain names, domains, IP addresses or other network CIDRs to exclude proxying.

    Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass proxy for all destinations. If you scale up workers that are not included in the network defined by the networking.machineNetwork[].cidr field from the installation configuration, you must add them to this list to prevent connection issues.

    This field is ignored if neither the httpProxy or httpsProxy fields are set.

    4
    One or more URLs external to the cluster to use to perform a readiness check before writing the httpProxy and httpsProxy values to status.
    5
    A reference to the ConfigMap in the openshift-config namespace that contains additional CA certificates required for proxying HTTPS connections. Note that the ConfigMap must already exist before referencing it here. This field is required unless the proxy’s identity certificate is signed by an authority from the RHCOS trust bundle.
  4. Save the file to apply the changes.

18.3. Certificate injection using Operators

Once your custom CA certificate is added to the cluster via ConfigMap, the Cluster Network Operator merges the user-provided and system CA certificates into a single bundle and injects the merged bundle into the Operator requesting the trust bundle injection.

Operators request this injection by creating an empty ConfigMap with the following label:

config.openshift.io/inject-trusted-cabundle="true"

An example of the empty ConfigMap:

apiVersion: v1
data: {}
kind: ConfigMap
metadata:
  labels:
    config.openshift.io/inject-trusted-cabundle: "true"
  name: ca-inject 1
  namespace: apache
1
Specifies the empty ConfigMap name.

The Operator mounts this ConfigMap into the container’s local trust store.

Note

Adding a trusted CA certificate is only needed if the certificate is not included in the Red Hat Enterprise Linux CoreOS (RHCOS) trust bundle.

Certificate injection is not limited to Operators. The Cluster Network Operator injects certificates across any namespace when an empty ConfigMap is created with the config.openshift.io/inject-trusted-cabundle=true label.

The ConfigMap can reside in any namespace, but the ConfigMap must be mounted as a volume to each container within a pod that requires a custom CA. For example:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-example-custom-ca-deployment
  namespace: my-example-custom-ca-ns
spec:
  ...
    spec:
      ...
      containers:
        - name: my-container-that-needs-custom-ca
          volumeMounts:
          - name: trusted-ca
            mountPath: /etc/pki/ca-trust/extracted/pem
            readOnly: true
      volumes:
      - name: trusted-ca
        configMap:
          name: trusted-ca
          items:
            - key: ca-bundle.crt 1
              path: tls-ca-bundle.pem 2
1
ca-bundle.crt is required as the ConfigMap key.
2
tls-ca-bundle.pem is required as the ConfigMap path.

Chapter 19. Load balancing on RHOSP

19.1. Using the Octavia OVN load balancer provider driver with Kuryr SDN

If your OpenShift Container Platform cluster uses Kuryr and was installed on a Red Hat OpenStack Platform (RHOSP) 13 cloud that was later upgraded to RHOSP 16, you can configure it to use the Octavia OVN provider driver.

Important

Kuryr replaces existing load balancers after you change provider drivers. This process results in some downtime.

Prerequisites

  • Install the RHOSP CLI, openstack.
  • Install the OpenShift Container Platform CLI, oc.
  • Verify that the Octavia OVN driver on RHOSP is enabled.

    Tip

    To view a list of available Octavia drivers, on a command line, enter openstack loadbalancer provider list.

    The ovn driver is displayed in the command’s output.

Procedure

To change from the Octavia Amphora provider driver to Octavia OVN:

  1. Open the kuryr-config ConfigMap. On a command line, enter:

    $ oc -n openshift-kuryr edit cm kuryr-config
  2. In the ConfigMap, delete the line that contains kuryr-octavia-provider: default. For example:

    ...
    kind: ConfigMap
    metadata:
      annotations:
        networkoperator.openshift.io/kuryr-octavia-provider: default 1
    ...
    1
    Delete this line. The cluster will regenerate it with ovn as the value.

    Wait for the Cluster Network Operator to detect the modification and to redeploy the kuryr-controller and kuryr-cni pods. This process might take several minutes.

  3. Verify that the kuryr-config ConfigMap annotation is present with ovn as its value. On a command line, enter:

    $ oc -n openshift-kuryr edit cm kuryr-config

    The ovn provider value is displayed in the output:

    ...
    kind: ConfigMap
    metadata:
      annotations:
        networkoperator.openshift.io/kuryr-octavia-provider: ovn
    ...
  4. Verify that RHOSP recreated its load balancers.

    1. On a command line, enter:

      $ openstack loadbalancer list | grep amphora

      A single Amphora load balancer is displayed. For example:

      a4db683b-2b7b-4988-a582-c39daaad7981 | ostest-7mbj6-kuryr-api-loadbalancer  | 84c99c906edd475ba19478a9a6690efd | 172.30.0.1     | ACTIVE              | amphora
    2. Search for ovn load balancers by entering:

      $ openstack loadbalancer list | grep ovn

      The remaining load balancers of the ovn type are displayed. For example:

      2dffe783-98ae-4048-98d0-32aa684664cc | openshift-apiserver-operator/metrics | 84c99c906edd475ba19478a9a6690efd | 172.30.167.119 | ACTIVE              | ovn
      0b1b2193-251f-4243-af39-2f99b29d18c5 | openshift-etcd/etcd                  | 84c99c906edd475ba19478a9a6690efd | 172.30.143.226 | ACTIVE              | ovn
      f05b07fc-01b7-4673-bd4d-adaa4391458e | openshift-dns-operator/metrics       | 84c99c906edd475ba19478a9a6690efd | 172.30.152.27  | ACTIVE              | ovn

19.2. Scaling clusters for application traffic by using Octavia

OpenShift Container Platform clusters that run on Red Hat OpenStack Platform (RHOSP) can use the Octavia load balancing service to distribute traffic across multiple virtual machines (VMs) or floating IP addresses. This feature mitigates the bottleneck that single machines or addresses create.

If your cluster uses Kuryr, the Cluster Network Operator created an internal Octavia load balancer at deployment. You can use this load balancer for application network scaling.

If your cluster does not use Kuryr, you must create your own Octavia load balancer to use it for application network scaling.

19.2.1. Scaling clusters by using Octavia

If you want to use multiple API load balancers, or if your cluster does not use Kuryr, create an Octavia load balancer and then configure your cluster to use it.

Prerequisites

  • Octavia is available on your Red Hat OpenStack Platform (RHOSP) deployment.

Procedure

  1. From a command line, create an Octavia load balancer that uses the Amphora driver:

    $ openstack loadbalancer create --name API_OCP_CLUSTER --vip-subnet-id <id_of_worker_vms_subnet>

    You can use a name of your choice instead of API_OCP_CLUSTER.

  2. After the load balancer becomes active, create listeners:

    $ openstack loadbalancer listener create --name API_OCP_CLUSTER_6443 --protocol HTTPS--protocol-port 6443 API_OCP_CLUSTER
    Note

    To view the status of the load balancer, enter openstack loadbalancer list.

  3. Create a pool that uses the round robin algorithm and has session persistence enabled:

    $ openstack loadbalancer pool create --name API_OCP_CLUSTER_pool_6443 --lb-algorithm ROUND_ROBIN --session-persistence type=<source_IP_address> --listener API_OCP_CLUSTER_6443 --protocol HTTPS
  4. To ensure that control plane machines are available, create a health monitor:

    $ openstack loadbalancer healthmonitor create --delay 5 --max-retries 4 --timeout 10 --type TCP API_OCP_CLUSTER_pool_6443
  5. Add the control plane machines as members of the load balancer pool:

    $ for SERVER in $(MASTER-0-IP MASTER-1-IP MASTER-2-IP)
    do
      openstack loadbalancer member create --address $SERVER  --protocol-port 6443 API_OCP_CLUSTER_pool_6443
    done
  6. Optional: To reuse the cluster API floating IP address, unset it:

    $ openstack floating ip unset $API_FIP
  7. Add either the unset API_FIP or a new address to the created load balancer VIP:

    $ openstack floating ip set  --port $(openstack loadbalancer show -c <vip_port_id> -f value API_OCP_CLUSTER) $API_FIP

Your cluster now uses Octavia for load balancing.

Note

If Kuryr uses the Octavia Amphora driver, all traffic is routed through a single Amphora virtual machine (VM).

You can repeat this procedure to create additional load balancers, which can alleviate the bottleneck.

19.2.2. Scaling clusters that use Kuryr by using Octavia

If your cluster uses Kuryr, associate the API floating IP address of your cluster with the pre-existing Octavia load balancer.

Prerequisites

  • Your OpenShift Container Platform cluster uses Kuryr.
  • Octavia is available on your Red Hat OpenStack Platform (RHOSP) deployment.

Procedure

  1. Optional: From a command line, to reuse the cluster API floating IP address, unset it:

    $ openstack floating ip unset $API_FIP
  2. Add either the unset API_FIP or a new address to the created load balancer VIP:

    $ openstack floating ip set --port $(openstack loadbalancer show -c <vip_port_id> -f value ${OCP_CLUSTER}-kuryr-api-loadbalancer) $API_FIP

Your cluster now uses Octavia for load balancing.

Note

If Kuryr uses the Octavia Amphora driver, all traffic is routed through a single Amphora virtual machine (VM).

You can repeat this procedure to create additional load balancers, which can alleviate the bottleneck.

19.3. Scaling for ingress traffic by using RHOSP Octavia

You can use Octavia load balancers to scale Ingress controllers on clusters that use Kuryr.

Prerequisites

  • Your OpenShift Container Platform cluster uses Kuryr.
  • Octavia is available on your RHOSP deployment.

Procedure

  1. To copy the current internal router service, on a command line, enter:

    $ oc -n openshift-ingress get svc router-internal-default -o yaml > external_router.yaml
  2. In the file external_router.yaml, change the values of metadata.name and spec.type to LoadBalancer.

    Example router file

    apiVersion: v1
    kind: Service
    metadata:
      labels:
        ingresscontroller.operator.openshift.io/owning-ingresscontroller: default
      name: router-external-default 1
      namespace: openshift-ingress
    spec:
      ports:
      - name: http
        port: 80
        protocol: TCP
        targetPort: http
      - name: https
        port: 443
        protocol: TCP
        targetPort: https
      - name: metrics
        port: 1936
        protocol: TCP
        targetPort: 1936
      selector:
        ingresscontroller.operator.openshift.io/deployment-ingresscontroller: default
      sessionAffinity: None
      type: LoadBalancer 2

    1
    Ensure that this value is descriptive, like router-external-default.
    2
    Ensure that this value is LoadBalancer.
Note

You can delete timestamps and other information that is irrelevant to load balancing.

  1. From a command line, create a service from the external_router.yaml file:

    $ oc apply -f external_router.yaml
  2. Verify that the external IP address of the service is the same as the one that is associated with the load balancer:

    1. On a command line, retrieve the external IP address of the service:

      $ oc -n openshift-ingress get svc

      Example output

      NAME                      TYPE           CLUSTER-IP       EXTERNAL-IP    PORT(S)                                     AGE
      router-external-default   LoadBalancer   172.30.235.33    10.46.22.161   80:30112/TCP,443:32359/TCP,1936:30317/TCP   3m38s
      router-internal-default   ClusterIP      172.30.115.123   <none>         80/TCP,443/TCP,1936/TCP                     22h

    2. Retrieve the IP address of the load balancer:

      $ openstack loadbalancer list | grep router-external

      Example output

      | 21bf6afe-b498-4a16-a958-3229e83c002c | openshift-ingress/router-external-default | 66f3816acf1b431691b8d132cc9d793c | 172.30.235.33  | ACTIVE | octavia |

    3. Verify that the addresses you retrieved in the previous steps are associated with each other in the floating IP list:

      $ openstack floating ip list | grep 172.30.235.33

      Example output

      | e2f80e97-8266-4b69-8636-e58bacf1879e | 10.46.22.161 | 172.30.235.33 | 655e7122-806a-4e0a-a104-220c6e17bda6 | a565e55a-99e7-4d15-b4df-f9d7ee8c9deb | 66f3816acf1b431691b8d132cc9d793c |

You can now use the value of EXTERNAL-IP as the new Ingress address.

Note

If Kuryr uses the Octavia Amphora driver, all traffic is routed through a single Amphora virtual machine (VM).

You can repeat this procedure to create additional load balancers, which can alleviate the bottleneck.

Chapter 20. Associating secondary interfaces metrics to network attachments

20.1. Associating secondary interfaces metrics to network attachments

Secondary devices, or interfaces, are used for different purposes. It is important to have a way to classify them in order to be able to aggregate the metrics for secondary devices with the same classification.

Exposed metrics contain the interface but do not specify where the interface originates. This is workable when there are no additional interfaces, but if a secondary interface is added, it is difficult to make use of the metrics since it is hard to identify the interfaces using only the interface name as an identifier.

When adding secondary interfaces, their names depend on the order in which they are added, and different secondary interfaces might belong to different networks and can be used for different purposes.

With pod_network_name_info it is possible to extend the current metrics with the additional information that identifies the interface type. In this way, it is possible to aggregate the metrics and to add specific alarms to specific interface types.

The network type is generated using the name of the related NetworkAttachmentDefinition, that in turn is used to differentiate different classes of secondary networks. For example, different interfaces belonging to different networks or using different CNIs use different network attachment definition names.

20.1.1. Network Metrics Daemon

The Network Metrics Daemon is a daemon component that collects and publishes network related metrics.

The kubelet is already publishing network related metrics you can observe. These metrics are:

  • container_network_receive_bytes_total
  • container_network_receive_errors_total
  • container_network_receive_packets_total
  • container_network_receive_packets_dropped_total
  • container_network_transmit_bytes_total
  • container_network_transmit_errors_total
  • container_network_transmit_packets_total
  • container_network_transmit_packets_dropped_total

The labels in these metrics contain, among others:

  • Pod name
  • Pod namespace
  • Interface name (such as eth0)

These metrics work well until new interfaces are added to the Pod, for example via Multus, as it is not clear what the interface names refer to.

The interface label refers to the interface name, but it is not clear what that interface is meant for. In case of many different interfaces, it would be impossible to understand what network the metrics you are monitoring refer to.

This is addressed by introducing the new pod_network_name_info described in the following section.

20.1.2. Metrics with network name

This daemonset publishes a pod_network_name_info gauge metric, with a fixed value of 0:

pod_network_name_info{interface="net0",namespace="namespacename",network_name="nadnamespace/firstNAD",pod="podname"} 0

The network name label is produced using the annotation added by Multus. It ia the concatenation of the namespace the network attachment definition belongs to, plus the name of the network attachment definition.

The new metric alone does not provide much value, but combined with the network related container_network_* metrics, it offers better support for monitoring secondary networks.

Using a promql query like the following ones, it is possible to get a new metric containing the value and the network name retrieved from the k8s.v1.cni.cncf.io/networks-status annotation:

(container_network_receive_bytes_total) + on(namespace,pod,interface) group_left(network_name) ( pod_network_name_info )
(container_network_receive_errors_total) + on(namespace,pod,interface) group_left(network_name) ( pod_network_name_info )
(container_network_receive_packets_total) + on(namespace,pod,interface) group_left(network_name) ( pod_network_name_info )
(container_network_receive_packets_dropped_total) + on(namespace,pod,interface) group_left(network_name) ( pod_network_name_info )
(container_network_transmit_bytes_total) + on(namespace,pod,interface) group_left(network_name) ( pod_network_name_info )
(container_network_transmit_errors_total) + on(namespace,pod,interface) group_left(network_name) ( pod_network_name_info )
(container_network_transmit_packets_total) + on(namespace,pod,interface) group_left(network_name) ( pod_network_name_info )
(container_network_transmit_packets_dropped_total) + on(namespace,pod,interface) group_left(network_name)

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