Prerequisites

Internet access for OpenShift Container Platform

In OpenShift Container Platform 4.8, 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.

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.

Generating a key pair for cluster node SSH access

During an OpenShift Container Platform installation, you can provide an SSH public key to the installation program. The key is passed to the Red Hat Enterprise Linux CoreOS (RHCOS) nodes through their Ignition config files and is used to authenticate SSH access to the nodes. The key is added to the ~/.ssh/authorized_keys list for the core user on each node, which enables password-less authentication.

After the key is passed to the nodes, you can use the key pair to SSH in to the RHCOS nodes as the user core. To access the nodes through SSH, the private key identity must be managed by SSH for your local user.

If you want to SSH in to your cluster nodes to perform installation debugging or disaster recovery, you must provide the SSH public key during the installation process. The ./openshift-install gather command also requires the SSH public key to be in place on the cluster nodes.

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

You must use a local key, not one that you configured with platform-specific approaches such as AWS key pairs.

Procedure
  1. If you do not have an existing SSH key pair on your local machine to use for authentication onto your cluster nodes, 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.

    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. View the public SSH key:

    $ cat <path>/<file_name>.pub

    For example, run the following to view the ~/.ssh/id_rsa.pub public key:

    $ cat ~/.ssh/id_rsa.pub
  3. Add the SSH private key identity to the SSH agent for your local user, if it has not already been added. SSH agent management of the key is required for password-less SSH authentication onto your cluster nodes, or if you want to use the ./openshift-install gather command.

    On some distributions, default SSH private key identities such as ~/.ssh/id_rsa and ~/.ssh/id_dsa are managed automatically.

    1. If the ssh-agent process is not already running for your local user, start it as a background task:

      $ eval "$(ssh-agent -s)"
      Example output
      Agent pid 31874

      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.

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

    $ ssh-add <path>/<file_name> (1)
    1 Specify the path and file name for your SSH private key, such as ~/.ssh/id_rsa
    Example output
    Identity added: /home/<you>/<path>/<file_name> (<computer_name>)
Next steps
  • When you install OpenShift Container Platform, provide the SSH public key to the installation program.

Obtaining the installation program

Before you install OpenShift Container Platform, download the installation file on a local computer.

Prerequisites
  • You have a computer that runs Linux or macOS, 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.

    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.

    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. 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.

Deploying the cluster

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

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

Prerequisites
  • Configure an account with the cloud platform that hosts your cluster.

  • Obtain the OpenShift Container Platform installation program and the pull secret for your cluster.

Procedure
  1. 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.

    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.

    Provide values at the prompts:

    1. Optional: Select an SSH key to use to access your cluster machines.

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

    2. Select azure as the platform to target.

    3. If you do not have a Microsoft Azure profile stored on your computer, specify the following Azure parameter values for your subscription and service principal:

      • azure subscription id: The subscription ID to use for the cluster. Specify the id value in your account output.

      • azure tenant id: The tenant ID. Specify the tenantId value in your account output.

      • azure service principal client id: The value of the appId parameter for the service principal.

      • azure service principal client secret: The value of the password parameter for the service principal.

    4. Select the region to deploy the cluster to.

    5. Select the base domain to deploy the cluster to. The base domain corresponds to the Azure DNS Zone that you created for your cluster.

    6. Enter a descriptive name for your cluster.

      All Azure resources that are available through public endpoints are subject to resource name restrictions, and 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.

    7. Paste the pull secret that you obtained from the Pull Secret page on the Red Hat OpenShift Cluster Manager site.

    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

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

    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.

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

Installing the OpenShift CLI by downloading the binary

You can install the OpenShift CLI (oc) to interact with OpenShift Container Platform from a command-line interface. You can install oc on Linux, Windows, or macOS.

If you installed an earlier version of oc, you cannot use it to complete all of the commands in OpenShift Container Platform 4.8. Download and install the new version of oc.

Installing the OpenShift CLI on Linux

You can install the OpenShift CLI (oc) binary on Linux by using the following procedure.

Procedure
  1. Navigate to the OpenShift Container Platform downloads page on the Red Hat Customer Portal.

  2. Select the appropriate version in the Version drop-down menu.

  3. Click Download Now next to the OpenShift v4.8 Linux Client entry and save the file.

  4. Unpack the archive:

    $ tar xvzf <file>
  5. Place the oc binary in a directory that is on your PATH.

    To check your PATH, execute the following command:

    $ echo $PATH

After you install the OpenShift CLI, it is available using the oc command:

$ oc <command>

Installing the OpenShift CLI on Windows

You can install the OpenShift CLI (oc) binary on Windows by using the following procedure.

Procedure
  1. Navigate to the OpenShift Container Platform downloads page on the Red Hat Customer Portal.

  2. Select the appropriate version in the Version drop-down menu.

  3. Click Download Now next to the OpenShift v4.8 Windows Client entry and save the file.

  4. Unzip the archive with a ZIP program.

  5. Move the oc binary to a directory that is on your PATH.

    To check your PATH, open the command prompt and execute the following command:

    C:\> path

After you install the OpenShift CLI, it is available using the oc command:

C:\> oc <command>

Installing the OpenShift CLI on macOS

You can install the OpenShift CLI (oc) binary on macOS by using the following procedure.

Procedure
  1. Navigate to the OpenShift Container Platform downloads page on the Red Hat Customer Portal.

  2. Select the appropriate version in the Version drop-down menu.

  3. Click Download Now next to the OpenShift v4.8 MacOSX Client entry and save the file.

  4. Unpack and unzip the archive.

  5. Move the oc binary to a directory on your PATH.

    To check your PATH, open a terminal and execute the following command:

    $ echo $PATH

After you install the OpenShift CLI, it is available using the oc command:

$ oc <command>

Logging in to the cluster by using the CLI

You can log in to your cluster as a default system user by exporting the cluster kubeconfig file. The kubeconfig file contains information about the cluster that is used by the CLI to connect a client to the correct cluster and API server. The file is specific to a cluster and is created during OpenShift Container Platform installation.

Prerequisites
  • You deployed an OpenShift Container Platform cluster.

  • You installed the oc CLI.

Procedure
  1. Export the kubeadmin credentials:

    $ export KUBECONFIG=<installation_directory>/auth/kubeconfig (1)
    1 For <installation_directory>, specify the path to the directory that you stored the installation files in.
  2. Verify you can run oc commands successfully using the exported configuration:

    $ oc whoami
    Example output
    system:admin
Additional resources
  • See Accessing the web console for more details about accessing and understanding the OpenShift Container Platform web console.

Telemetry access for OpenShift Container Platform

In OpenShift Container Platform 4.8, the Telemetry service, which runs by default to provide metrics about cluster health and the success of updates, requires internet access. If your cluster is connected to the internet, Telemetry runs automatically, and your cluster is registered to the Red Hat OpenShift Cluster Manager (OCM).

After you confirm that your Red Hat OpenShift Cluster Manager inventory is correct, either maintained automatically by Telemetry or manually by using OCM, use subscription watch to track your OpenShift Container Platform subscriptions at the account or multi-cluster level.

Additional resources

Next steps