Chapter 13. Installing on RHV

13.1. Installing a cluster quickly on RHV

You can quickly install a default, non-customized, OpenShift Container Platform cluster on a Red Hat Virtualization (RHV) cluster, similar to the one shown in the following diagram.

Diagram of an OpenShift Container Platform cluster on a RHV cluster

The installation program uses installer-provisioned infrastructure to automate creating and deploying the cluster.

To install a default cluster, you prepare the environment, run the installation program and answer its prompts. Then, the installation program creates the OpenShift Container Platform cluster.

For an alternative to installing a default cluster, see Installing a cluster with customizations.

Note

This installation program is available for Linux and macOS only.

13.1.1. Prerequisites

13.1.2. Internet access for OpenShift Container Platform

In OpenShift Container Platform 4.7, you require access to the Internet to install your cluster.

You must have Internet access to:

  • Access the Red Hat OpenShift Cluster Manager page to download the installation program and perform subscription management. If the cluster has Internet access and you do not disable Telemetry, that service automatically entitles your cluster.
  • Access Quay.io to obtain the packages that are required to install your cluster.
  • Obtain the packages that are required to perform cluster updates.
Important

If your cluster cannot have direct Internet access, you can perform a restricted network installation on some types of infrastructure that you provision. During that process, you download the content that is required and use it to populate a mirror registry with the packages that you need to install a cluster and generate the installation program. With some installation types, the environment that you install your cluster in will not require Internet access. Before you update the cluster, you update the content of the mirror registry.

13.1.3. Requirements for the RHV environment

To install and run an OpenShift Container Platform version 4.7 cluster, the RHV environment must meet the following requirements.

Not meeting these requirements can cause the installation or process to fail. Additionally, not meeting these requirements can cause the OpenShift Container Platform cluster to fail days or weeks after installation.

The following requirements for CPU, memory, and storage resources are based on default values multiplied by the default number of virtual machines the installation program creates. These resources must be available in addition to what the RHV environment uses for non-OpenShift Container Platform operations.

By default, the installation program creates seven virtual machines during the installation process. First, it creates a bootstrap virtual machine to provide temporary services and a control plane while it creates the rest of the OpenShift Container Platform cluster. When the installation program finishes creating the cluster, deleting the bootstrap machine frees up its resources.

If you increase the number of virtual machines in the RHV environment, you must increase the resources accordingly.

Requirements

  • The RHV version is 4.4.
  • The RHV environment has one data center whose state is Up.
  • The RHV data center contains an RHV cluster.
  • The RHV cluster has the following resources exclusively for the OpenShift Container Platform cluster:

    • Minimum 28 vCPUs: four for each of the seven virtual machines created during installation.
    • 112 GiB RAM or more, including:

      • 16 GiB or more for the bootstrap machine, which provides the temporary control plane.
      • 16 GiB or more for each of the three control plane machines which provide the control plane.
      • 16 GiB or more for each of the three compute machines, which run the application workloads.
  • The RHV storage domain must meet these etcd backend performance requirements.
  • In production environments, each virtual machine must have 120 GiB or more. Therefore, the storage domain must provide 840 GiB or more for the default OpenShift Container Platform cluster. In resource-constrained or non-production environments, each virtual machine must have 32 GiB or more, so the storage domain must have 230 GiB or more for the default OpenShift Container Platform cluster.
  • To download images from the Red Hat Ecosystem Catalog during installation and update procedures, the RHV cluster must have access to an internet connection. The Telemetry service also needs an internet connection to simplify the subscription and entitlement process.
  • The RHV cluster must have a virtual network with access to the REST API on the RHV Manager. Ensure that DHCP is enabled on this network, because the VMs that the installer creates obtain their IP address by using DHCP.
  • A user account and group with the following least privileges for installing and managing an OpenShift Container Platform cluster on the target RHV cluster:

    • DiskOperator
    • DiskCreator
    • UserTemplateBasedVm
    • TemplateOwner
    • TemplateCreator
    • ClusterAdmin on the target cluster
Warning

Apply the principle of least privilege: Avoid using an administrator account with SuperUser privileges on RHV during the installation process. The installation program saves the credentials you provide to a temporary ovirt-config.yaml file that might be compromised.

13.1.4. Verifying the requirements for the RHV environment

Verify that the RHV environment meets the requirements to install and run an OpenShift Container Platform cluster. Not meeting these requirements can cause failures.

Important

These requirements are based on the default resources the installation program uses to create control plane and compute machines. These resources include vCPUs, memory, and storage. If you change these resources or increase the number of OpenShift Container Platform machines, adjust these requirements accordingly.

Procedure

  1. Check that the RHV version supports installation of OpenShift Container Platform version 4.7.

    1. In the RHV Administration Portal, click the ? help icon in the upper-right corner and select About.
    2. In the window that opens, make a note of the RHV Software Version.
    3. Confirm that the RHV version is 4.4. For more information about supported version combinations, see Support Matrix for OpenShift Container Platform on RHV.
  2. Inspect the data center, cluster, and storage.

    1. In the RHV Administration Portal, click ComputeData Centers.
    2. Confirm that the data center where you plan to install OpenShift Container Platform is accessible.
    3. Click the name of that data center.
    4. In the data center details, on the Storage tab, confirm the storage domain where you plan to install OpenShift Container Platform is Active.
    5. Record the Domain Name for use later on.
    6. Confirm Free Space has at least 230 GiB.
    7. Confirm that the storage domain meets these etcd backend performance requirements, which you can measure by using the fio performance benchmarking tool.
    8. In the data center details, click the Clusters tab.
    9. Find the RHV cluster where you plan to install OpenShift Container Platform. Record the cluster name for use later on.
  3. Inspect the RHV host resources.

    1. In the RHV Administration Portal, click Compute > Clusters.
    2. Click the cluster where you plan to install OpenShift Container Platform.
    3. In the cluster details, click the Hosts tab.
    4. Inspect the hosts and confirm they have a combined total of at least 28 Logical CPU Cores available exclusively for the OpenShift Container Platform cluster.
    5. Record the number of available Logical CPU Cores for use later on.
    6. Confirm that these CPU cores are distributed so that each of the seven virtual machines created during installation can have four cores.
    7. Confirm that, all together, the hosts have 112 GiB of Max free Memory for scheduling new virtual machines distributed to meet the requirements for each of the following OpenShift Container Platform machines:

      • 16 GiB required for the bootstrap machine
      • 16 GiB required for each of the three control plane machines
      • 16 GiB for each of the three compute machines
    8. Record the amount of Max free Memory for scheduling new virtual machines for use later on.
  4. Verify that the virtual network for installing OpenShift Container Platform has access to the RHV Manager’s REST API. From a virtual machine on this network, use curl to reach the RHV Manager’s REST API:

    $ curl -k -u <username>@<profile>:<password> \ 1
    https://<engine-fqdn>/ovirt-engine/api 2
    1
    For <username>, specify the user name of an RHV account with privileges to create and manage an OpenShift Container Platform cluster on RHV. For <profile>, specify the login profile, which you can get by going to the RHV Administration Portal login page and reviewing the Profile dropdown list. For <password>, specify the password for that user name.
    2
    For <engine-fqdn>, specify the fully qualified domain name of the RHV environment.

    For example:

    $ curl -k -u ocpadmin@internal:pw123 \
    https://rhv-env.virtlab.example.com/ovirt-engine/api

13.1.5. Preparing the network environment on RHV

Configure two static IP addresses for the OpenShift Container Platform cluster and create DNS entries using these addresses.

Procedure

  1. Reserve two static IP addresses

    1. On the network where you plan to install OpenShift Container Platform, identify two static IP addresses that are outside the DHCP lease pool.
    2. Connect to a host on this network and verify that each of the IP addresses is not in use. For example, use Address Resolution Protocol (ARP) to check that none of the IP addresses have entries:

      $ arp 10.35.1.19

      Example output

      10.35.1.19 (10.35.1.19) -- no entry

    3. Reserve two static IP addresses following the standard practices for your network environment.
    4. Record these IP addresses for future reference.
  2. Create DNS entries for the OpenShift Container Platform REST API and apps domain names using this format:

    api.<cluster-name>.<base-domain>   <ip-address> 1
    *.apps.<cluster-name>.<base-domain>   <ip-address> 2
    1
    For <cluster-name>, <base-domain>, and <ip-address>, specify the cluster name, base domain, and static IP address of your OpenShift Container Platform API.
    2
    Specify the cluster name, base domain, and static IP address of your OpenShift Container Platform apps for Ingress and the load balancer.

    For example:

    api.my-cluster.virtlab.example.com	10.35.1.19
    *.apps.my-cluster.virtlab.example.com	10.35.1.20

13.1.6. Installing OpenShift Container Platform on RHV in insecure mode

By default, the installer creates a CA certificate, prompts you for confirmation, and stores the certificate to use during installation. You do not need to create or install one manually.

Although it is not recommended, you can override this functionality and install OpenShift Container Platform without verifying a certificate by installing OpenShift Container Platform on RHV in insecure mode.

Warning

Installing in insecure mode is not recommended, because it enables a potential attacker to perform a Man-in-the-Middle attack and capture sensitive credentials on the network.

Procedure

  1. Create a file named ~/.ovirt/ovirt-config.yaml.
  2. Add the following content to ovirt-config.yaml:

    ovirt_url: \https://ovirt.example.com/ovirt-engine/api
    ovirt_fqdn: ovirt.example.com
    ovirt_pem_url: ""
    ovirt_username: ocpadmin@internal
    ovirt_password: super-secret-password
    ovirt_insecure: true
  3. Run the installer.

13.1.7. Generating an SSH private key and adding it to the agent

If you want to perform installation debugging or disaster recovery on your cluster, you must provide an SSH key to both your ssh-agent and the installation program. You can use this key to access the bootstrap machine in a public cluster to troubleshoot installation issues.

Note

In a production environment, you require disaster recovery and debugging.

Important

Do not skip this procedure in production environments where disaster recovery and debugging is required.

You can use this key to SSH into the master nodes as the user core. When you deploy the cluster, the key is added to the core user’s ~/.ssh/authorized_keys list.

Procedure

  1. If you do not have an SSH key that is configured for password-less authentication on your computer, create one. For example, on a computer that uses a Linux operating system, run the following command:

    $ ssh-keygen -t ed25519 -N '' \
        -f <path>/<file_name> 1
    1
    Specify the path and file name, such as ~/.ssh/id_rsa, of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory.

    Running this command generates an SSH key that does not require a password in the location that you specified.

    Note

    If you plan to install an OpenShift Container Platform cluster that uses FIPS Validated / Modules in Process cryptographic libraries on the x86_64 architecture, do not create a key that uses the ed25519 algorithm. Instead, create a key that uses the rsa or ecdsa algorithm.

  2. Start the ssh-agent process as a background task:

    $ eval "$(ssh-agent -s)"

    Example output

    Agent pid 31874

    Note

    If your cluster is in FIPS mode, only use FIPS-compliant algorithms to generate the SSH key. The key must be either RSA or ECDSA.

  3. Add your SSH private key to the ssh-agent:

    $ ssh-add <path>/<file_name> 1

    Example output

    Identity added: /home/<you>/<path>/<file_name> (<computer_name>)

    1
    Specify the path and file name for your SSH private key, such as ~/.ssh/id_rsa
  4. Set the GOOGLE_APPLICATION_CREDENTIALS environment variable to the full path to your service account private key file.

    $ export GOOGLE_APPLICATION_CREDENTIALS="<your_service_account_file>"
  5. Verify that the credentials were applied.

    $ gcloud auth list

Next steps

  • When you install OpenShift Container Platform, provide the SSH public key to the installation program.

13.1.8. Obtaining the installation program

Before you install OpenShift Container Platform, download the installation file on your provisioning machine.

Prerequisites

  • You have a machine that runs Linux, for example Red Hat Enterprise Linux 8, with 500 MB of local disk space

Procedure

  1. Access the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site. If you have a Red Hat account, log in with your credentials. If you do not, create an account.
  2. Select your infrastructure provider.
  3. Navigate to the page for your installation type, download the installation program for your operating system, and place the file in the directory where you will store the installation configuration files.

    Important

    The installation program creates several files on the computer that you use to install your cluster. You must keep the installation program and the files that the installation program creates after you finish installing the cluster. Both files are required to delete the cluster.

    Important

    Deleting the files created by the installation program does not remove your cluster, even if the cluster failed during installation. To remove your cluster, complete the OpenShift Container Platform uninstallation procedures for your specific cloud provider.

  4. Extract the installation program. For example, on a computer that uses a Linux operating system, run the following command:

    $ tar xvf openshift-install-linux.tar.gz
  5. From the Pull Secret page on the Red Hat OpenShift Cluster Manager site, download your installation pull secret as a .txt file. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OpenShift Container Platform components.

13.1.9. Deploying the cluster

You can install OpenShift Container Platform on a compatible cloud platform.

Important

You can run the create cluster command of the installation program only once, during initial installation.

Prerequisites

  • Open the ovirt-imageio port to the Manager from the machine running the installer. By default, the port is 54322.
  • Obtain the OpenShift Container Platform installation program and the pull secret for your cluster.

Procedure

  1. Remove any existing GCP credentials that do not use the service account key for the GCP account that you configured for your cluster and that are stored in the following locations:

    • The GOOGLE_CREDENTIALS, GOOGLE_CLOUD_KEYFILE_JSON, or GCLOUD_KEYFILE_JSON environment variables
    • The ~/.gcp/osServiceAccount.json file
    • The gcloud cli default credentials
  2. Change to the directory that contains the installation program and initialize the cluster deployment:

    $ ./openshift-install create cluster --dir=<installation_directory> \ 1
        --log-level=info 2
    1
    For <installation_directory>, specify the directory name to store the files that the installation program creates.
    2
    To view different installation details, specify warn, debug, or error instead of info.
    Important

    Specify an empty directory. Some installation assets, like bootstrap X.509 certificates have short expiration intervals, so you must not reuse an installation directory. If you want to reuse individual files from another cluster installation, you can copy them into your directory. However, the file names for the installation assets might change between releases. Use caution when copying installation files from an earlier OpenShift Container Platform version.

    Respond to the installation program prompts.

    1. Optional: For SSH Public Key, select a password-less public key, such as ~/.ssh/id_rsa.pub. This key authenticates connections with the new OpenShift Container Platform cluster.

      Note

      For production OpenShift Container Platform clusters on which you want to perform installation debugging or disaster recovery, select an SSH key that your ssh-agent process uses.

    2. For Platform, select ovirt.
    3. For Engine FQDN[:PORT], enter the fully qualified domain name (FQDN) of the RHV environment.

      For example:

      rhv-env.virtlab.example.com:443
    4. The installer automatically generates a CA certificate. For Would you like to use the above certificate to connect to the Manager?, answer y or N. If you answer N, you must install OpenShift Container Platform in insecure mode.
    5. For Engine username, enter the user name and profile of the RHV administrator using this format:

      <username>@<profile> 1
      1
      For <username>, specify the user name of an RHV administrator. For <profile>, specify the login profile, which you can get by going to the RHV Administration Portal login page and reviewing the Profile dropdown list. For example: admin@internal.
    6. For Engine password, enter the RHV admin password.
    7. For Cluster, select the RHV cluster for installing OpenShift Container Platform.
    8. For Storage domain, select the storage domain for installing OpenShift Container Platform.
    9. For Network, select a virtual network that has access to the RHV Manager REST API.
    10. For Internal API Virtual IP, enter the static IP address you set aside for the cluster’s REST API.
    11. For Ingress virtual IP, enter the static IP address you reserved for the wildcard apps domain.
    12. For Base Domain, enter the base domain of the OpenShift Container Platform cluster. If this cluster is exposed to the outside world, this must be a valid domain recognized by DNS infrastructure. For example, enter: virtlab.example.com
    13. For Cluster Name, enter the name of the cluster. For example, my-cluster. Use cluster name from the externally registered/resolvable DNS entries you created for the OpenShift Container Platform REST API and apps domain names. The installation program also gives this name to the cluster in the RHV environment.
    14. For Pull Secret, copy the pull secret from the pull-secret.txt file you downloaded earlier and paste it here. You can also get a copy of the same pull secret from the Pull Secret page on the Red Hat OpenShift Cluster Manager site.
    Note

    If the cloud provider account that you configured on your host does not have sufficient permissions to deploy the cluster, the installation process stops, and the missing permissions are displayed.

    When the cluster deployment completes, directions for accessing your cluster, including a link to its web console and credentials for the kubeadmin user, display in your terminal.

    Example output

    ...
    INFO Install complete!
    INFO To access the cluster as the system:admin user when using 'oc', run 'export KUBECONFIG=/home/myuser/install_dir/auth/kubeconfig'
    INFO Access the OpenShift web-console here: https://console-openshift-console.apps.mycluster.example.com
    INFO Login to the console with user: "kubeadmin", and password: "4vYBz-Ee6gm-ymBZj-Wt5AL"
    INFO Time elapsed: 36m22s

    Note

    The cluster access and credential information also outputs to <installation_directory>/.openshift_install.log when an installation succeeds.

    Important

    The Ignition config files that the installation program generates contain certificates that expire after 24 hours, which are then renewed at that time. If the cluster is shut down before renewing the certificates and the cluster is later restarted after the 24 hours have elapsed, the cluster automatically recovers the expired certificates. The exception is that you must manually approve the pending node-bootstrapper certificate signing requests (CSRs) to recover kubelet certificates. See the documentation for Recovering from expired control plane certificates for more information.

    Important

    You must not delete the installation program or the files that the installation program creates. Both are required to delete the cluster.

  3. Optional: You can reduce the number of permissions for the service account that you used to install the cluster.

    • If you assigned the Owner role to your service account, you can remove that role and replace it with the Viewer role.
    • If you included the Service Account Key Admin role, you can remove it.
Important

You have completed the steps required to install the cluster. The remaining steps show you how to verify the cluster and troubleshoot the installation.