Prerequisites

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.

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

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.

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

On clusters running Fedora CoreOS (FCOS), the SSH keys specified in the Ignition config files are written to the /home/core/.ssh/authorized_keys.d/core file. However, the Machine Config Operator manages SSH keys in the /home/core/.ssh/authorized_keys file and configures sshd to ignore the /home/core/.ssh/authorized_keys.d/core file. As a result, newly provisioned OKD nodes are not accessible using SSH until the Machine Config Operator reconciles the machine configs with the authorized_keys file. After you can access the nodes using SSH, you can delete the /home/core/.ssh/authorized_keys.d/core file.

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.

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

    $ eval "$(ssh-agent -s)"
    Example output
    Agent pid 31874
  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
Next steps
  • When you install OKD, provide the SSH public key to the installation program.

Obtaining the installation program

Before you install OKD, 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. Download installer from https://github.com/openshift/okd/releases

    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 OKD uninstallation procedures for your specific cloud provider.

  2. 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
  3. 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 OKD components.

    Using a pull secret from the Red Hat OpenShift Cluster Manager site is not required. You can use a pull secret for another private registry. Or, if you do not need the cluster to pull images from a private registry, you can use {"auths":{"fake":{"auth":"aWQ6cGFzcwo="}}} as the pull secret when prompted during the installation.

    If you do not use the pull secret from the Red Hat OpenShift Cluster Manager site:

    • Red Hat Operators are not available.

    • The Telemetry and Insights operators do not send data to Red Hat.

    • Content from the Red Hat Ecosystem Catalog Container images registry, such as image streams and Operators, are not available.

Creating the installation configuration file

You can customize the OKD cluster you install on Microsoft Azure.

Prerequisites
  • Obtain the OKD installation program and the pull secret for your cluster.

Procedure
  1. Create the install-config.yaml file.

    1. Change to the directory that contains the installation program and run the following command:

      $ ./openshift-install create install-config --dir=<installation_directory> (1)
      1 For <installation_directory>, specify the directory name to store the files that the installation program creates.

      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 OKD version.

    2. At the prompts, provide the configuration details for your cloud:

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

        For production OKD 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. This field is optional.

  2. Modify the install-config.yaml file. You can find more information about the available parameters in the Installation configuration parameters section.

  3. Back up the install-config.yaml file so that you can use it to install multiple clusters.

    The install-config.yaml file is consumed during the installation process. If you want to reuse the file, you must back it up now.

Installation configuration parameters

Before you deploy an OKD cluster, you provide parameter values to describe your account on the cloud platform that hosts your cluster and optionally customize your cluster’s platform. When you create the install-config.yaml installation configuration file, you provide values for the required parameters through the command line. If you customize your cluster, you can modify the install-config.yaml file to provide more details about the platform.

After installation, you cannot modify these parameters in the install-config.yaml file.

The openshift-install command does not validate field names for parameters. If an incorrect name is specified, the related file or object is not created, and no error is reported. Ensure that the field names for any parameters that are specified are correct.

Table 1. Required parameters
Parameter Description Values

apiVersion

The API version for the install-config.yaml content. The current version is v1. The installer may also support older API versions.

String

baseDomain

The base domain of your cloud provider. The base domain is used to create routes to your OKD cluster components. The full DNS name for your cluster is a combination of the baseDomain and metadata.name parameter values that uses the <metadata.name>.<baseDomain> format.

A fully-qualified domain or subdomain name, such as example.com.

metadata

Kubernetes resource ObjectMeta, from which only the name parameter is consumed.

Object

metadata.name

The name of the cluster. DNS records for the cluster are all subdomains of {{.metadata.name}}.{{.baseDomain}}.

String of lowercase letters, hyphens (-), and periods (.), such as dev.

platform

The configuration for the specific platform upon which to perform the installation: aws, baremetal, azure, openstack, ovirt, vsphere. For additional information about platform.<platform> parameters, consult the following table for your specific platform.

Object

Table 2. Optional parameters
Parameter Description Values

additionalTrustBundle

A PEM-encoded X.509 certificate bundle that is added to the nodes' trusted certificate store. This trust bundle may also be used when a proxy has been configured.

String

compute

The configuration for the machines that comprise the compute nodes.

Array of machine-pool objects. For details, see the following "Machine-pool" table.

compute.architecture

Determines the instruction set architecture of the machines in the pool. Currently, heteregeneous clusters are not supported, so all pools must specify the same architecture. Valid values are amd64 (the default).

String

compute.hyperthreading

Whether to enable or disable simultaneous multithreading, or hyperthreading, on compute machines. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance.

Enabled or Disabled

compute.name

Required if you use compute. The name of the machine pool.

worker

compute.platform

Required if you use compute. Use this parameter to specify the cloud provider to host the worker machines. This parameter value must match the controlPlane.platform parameter value.

aws, azure, gcp, openstack, ovirt, vsphere, or {}

compute.replicas

The number of compute machines, which are also known as worker machines, to provision.

A positive integer greater than or equal to 2. The default value is 3.

controlPlane

The configuration for the machines that comprise the control plane.

Array of MachinePool objects. For details, see the following "Machine-pool" table.

controlPlane.architecture

Determines the instruction set architecture of the machines in the pool. Currently, heterogeneous clusters are not supported, so all pools must specify the same architecture. Valid values are amd64 (the default).

String

controlPlane.hyperthreading

Whether to enable or disable simultaneous multithreading, or hyperthreading, on control plane machines. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance.

Enabled or Disabled

controlPlane.name

Required if you use controlPlane. The name of the machine pool.

master

controlPlane.platform

Required if you use controlPlane. Use this parameter to specify the cloud provider that hosts the control plane machines. This parameter value must match the compute.platform parameter value.

aws, azure, gcp, openstack, ovirt, vsphere, or {}

controlPlane.replicas

The number of control plane machines to provision.

The only supported value is 3, which is the default value.

credentialsMode

The Cloud Credential Operator (CCO) mode. If no mode is specified, the CCO dynamically tries to determine the capabilities of the provided credentials, with a preference for mint mode on the platforms where multiple modes are supported.

Not all CCO modes are supported for all cloud providers. For more information on CCO modes, see the Cloud Credential Operator entry in the Red Hat Operators reference content.

Mint, Passthrough, Manual, or an empty string ("").

imageContentSources

Sources and repositories for the release-image content.

Array of objects. Includes a source and, optionally, mirrors, as described in the following rows of this table.

imageContentSources.source

Required if you use imageContentSources. Specify the repository that users refer to, for example, in image pull specifications.

String

imageContentSources.mirrors

Specify one or more repositories that may also contain the same images.

Array of strings

networking

The configuration for the network for the cluster.

Object

You cannot modify parameters specified by the networking object after installation.

networking.networkType

The default Container Network Interface (CNI) network provider plug-in to install. Either OpenShiftSDN or OVNKubernetes. The default value is OVNKubernetes.

String

networking.clusterNetwork

The IP address blocks for pods. The default is 10.128.0.0/14 with a host prefix of /23. If you specify multiple IP address blocks, the blocks must not overlap.

Array of objects. For example:

networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23

networking.clusterNetwork.cidr

Required if you use networking.clusterNetwork. An IP address block.

IP network in Classless Inter-Domain Routing (CIDR) notation. For example, 10.128.0.0/14.

networking.clusterNetwork.hostPrefix

The subnet prefix length to assign to each individual node. For example, if hostPrefix is set to 23, then each node is assigned a /23 subnet out of the given cidr, allowing for 510 (2^(32 - 23) - 2) pod IP addresses.

A subnet prefix. The default value is 23.

networking.serviceNetwork

The IP address block for services. The default is 172.30.0.0/16.

The OpenShift SDN and OVN-Kubernetes Container Network Interface (CNI) network providers support only a single IP address block for the service network.

An IP address block in CIDR format. For example, 172.30.0.0/16.

networking:
  serviceNetwork:
   - 172.30.0.0/16

networking.machineNetwork

The IP address blocks for machines.

Array of objects

networking:
  machineNetwork:
  - cidr: 10.0.0.0/16

networking.machineNetwork.cidr

Required if you use networking.machineNetwork. An IP address block. The default is 10.0.0.0/16 for all platforms other than libvirt. For libvirt, the default is 192.168.126.0/24.

IP network in Classless Inter-Domain Routing (CIDR) notation. For example, 10.0.0.0/16.

Set the networking.machineNetwork to match the CIDR that the preferred NIC resides in.

publish

How to publish or expose the user-facing endpoints of your cluster, such as the Kubernetes API, OpenShift routes.

Internal or External. To deploy a private cluster, which cannot be accessed from the internet, set publish to Internal. The default value is External.

sshKey

The SSH key to authenticate access to your cluster machines.

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

For example, sshKey: ssh-ed25519 AAAA...

Table 3. Additional Azure parameters
Parameter Description Values

controlPlane.platform.azure.osDisk.diskSizeGB

The Azure disk size for the VM.

Integer that represents the size of the disk in GB. The minimum supported disk size is 1024.

platform.azure.baseDomainResourceGroupName

The name of the resource group that contains the DNS zone for your base domain.

String, for example production_cluster.

platform.azure.resourceGroupName

The name of an already existing resource group to install your cluster to. This resource group must be empty and only used for this specific cluster; the cluster components assume ownership of all resources in the resource group. If you limit the service principal scope of the installation program to this resource group, you must ensure all other resources used by the installation program in your environment have the necessary permissions, such as the public DNS zone and virtual network. Destroying the cluster using the installation program deletes this resource group.

String, for example existing_resource_group.

platform.azure.outboundType

The outbound routing strategy used to connect your cluster to the internet. If you are using user-defined routing, you must have pre-existing networking available where the outbound routing has already been configured prior to installing a cluster. The installation program is not responsible for configuring user-defined routing.

LoadBalancer or UserDefinedRouting. The default is LoadBalancer.

platform.azure.region

The name of the Azure region that hosts your cluster.

Any valid region name, such as centralus.

platform.azure.zone

List of availability zones to place machines in. For high availability, specify at least two zones.

List of zones, for example ["1", "2", "3"].

platform.azure.networkResourceGroupName

The name of the resource group that contains the existing VNet that you want to deploy your cluster to. This name cannot be the same as the platform.azure.baseDomainResourceGroupName.

String.

platform.azure.virtualNetwork

The name of the existing VNet that you want to deploy your cluster to.

String.

platform.azure.controlPlaneSubnet

The name of the existing subnet in your VNet that you want to deploy your control plane machines to.

Valid CIDR, for example 10.0.0.0/16.

platform.azure.computeSubnet

The name of the existing subnet in your VNet that you want to deploy your compute machines to.

Valid CIDR, for example 10.0.0.0/16.

platform.azure.cloudName

The name of the Azure cloud environment that is used to configure the Azure SDK with the appropriate Azure API endpoints. If empty, the default value AzurePublicCloud is used.

Any valid cloud environment, such as AzurePublicCloud or AzureUSGovernmentCloud.

You cannot customize Azure Availability Zones or Use tags to organize your Azure resources with an Azure cluster.

Sample customized install-config.yaml file for Azure

You can customize the install-config.yaml file to specify more details about your OKD cluster’s platform or modify the values of the required parameters.

This sample YAML file is provided for reference only. You must obtain your install-config.yaml file by using the installation program and modify it.

apiVersion: v1
baseDomain: example.com (1)
controlPlane: (2)
  hyperthreading: Enabled  (3) (4)
  name: master
  platform:
    azure:
      osDisk:
        diskSizeGB: 1024 (5)
      type: Standard_D8s_v3
  replicas: 3
compute: (2)
- hyperthreading: Enabled (3)
  name: worker
  platform:
    azure:
      type: Standard_D2s_v3
      osDisk:
        diskSizeGB: 512 (5)
      zones: (6)
      - "1"
      - "2"
      - "3"
  replicas: 5
metadata:
  name: test-cluster (1)
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16
  networkType: OVNKubernetes
  serviceNetwork:
  - 172.30.0.0/16
platform:
  azure:
    baseDomainResourceGroupName: resource_group (7)
    region: centralus (1)
    resourceGroupName: existing_resource_group (8)
    outboundType: Loadbalancer
    cloudName: AzurePublicCloud
pullSecret: '{"auths": ...}' (1)
sshKey: ssh-ed25519 AAAA... (9)
1 Required. The installation program prompts you for this value.
2 If you do not provide these parameters and values, the installation program provides the default value.
3 The controlPlane section is a single mapping, but the compute section is a sequence of mappings. To meet the requirements of the different data structures, the first line of the compute section must begin with a hyphen, -, and the first line of the controlPlane section must not. Although both sections currently define a single machine pool, it is possible that future versions of OKD will support defining multiple compute pools during installation. Only one control plane pool is used.
4 Whether to enable or disable simultaneous multithreading, or hyperthreading. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores. You can disable it by setting the parameter value to Disabled. If you disable simultaneous multithreading in some cluster machines, you must disable it in all cluster machines.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance. Use larger virtual machine types, such as Standard_D8s_v3, for your machines if you disable simultaneous multithreading.

5 You can specify the size of the disk to use in GB. Minimum recommendation for master nodes is 1024 GB.
6 Specify a list of zones to deploy your machines to. For high availability, specify at least two zones.
7 Specify the name of the resource group that contains the DNS zone for your base domain.
8 Specify the name of an already existing resource group to install your cluster to. If undefined, a new resource group is created for the cluster.
9 You can optionally provide the sshKey value that you use to access the machines in your cluster.

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

Deploying the cluster

You can install OKD 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 OKD 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 location of your customized ./install-config.yaml file.
    2 To view different installation details, specify warn, debug, or error instead of info.

    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 OKD 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 OKD 4. 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 https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.

  2. Download oc.tar.gz.

  3. Unpack the archive:

    $ tar xvzf <file>
  4. 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 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 https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.

  2. Download oc.zip.

  3. Unzip the archive with a ZIP program.

  4. 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 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 https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.

  2. Download oc.tar.gz.

  3. Unpack and unzip the archive.

  4. 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 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 OKD installation.

Prerequisites
  • You deployed an OKD 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

Next steps