×

Prerequisites

About using a custom VPC

In OKD 4, you can deploy a cluster into the subnets of an existing IBM® Virtual Private Cloud (VPC). Deploying OKD into an existing VPC can help you avoid limit constraints in new accounts or more easily abide by the operational constraints that your company’s guidelines set. If you cannot obtain the infrastructure creation permissions that are required to create the VPC yourself, use this installation option.

Because the installation program cannot know what other components are in your existing subnets, it cannot choose subnet CIDRs and so forth. You must configure networking for the subnets to which you will install the cluster.

Requirements for using your VPC

You must correctly configure the existing VPC and its subnets before you install the cluster. The installation program does not create the following components:

  • NAT gateways

  • Subnets

  • Route tables

  • VPC network

The installation program cannot:

  • Subdivide network ranges for the cluster to use

  • Set route tables for the subnets

  • Set VPC options like DHCP

The installation program requires that you use the cloud-provided DNS server. Using a custom DNS server is not supported and causes the installation to fail.

VPC validation

The VPC and all of the subnets must be in an existing resource group. The cluster is deployed to the existing VPC.

As part of the installation, specify the following in the install-config.yaml file:

  • The name of the existing resource group that contains the VPC and subnets (networkResourceGroupName)

  • The name of the existing VPC (vpcName)

  • The subnets that were created for control plane machines and compute machines (controlPlaneSubnets and computeSubnets)

Additional installer-provisioned cluster resources are deployed to a separate resource group (resourceGroupName). You can specify this resource group before installing the cluster. If undefined, a new resource group is created for the cluster.

To ensure that the subnets that you provide are suitable, the installation program confirms the following:

  • All of the subnets that you specify exist.

  • For each availability zone in the region, you specify:

    • One subnet for control plane machines.

    • One subnet for compute machines.

  • The machine CIDR that you specified contains the subnets for the compute machines and control plane machines.

Subnet IDs are not supported.

Isolation between clusters

If you deploy OKD to an existing network, the isolation of cluster services is reduced in the following ways:

  • You can install multiple OKD clusters in the same VPC.

  • ICMP ingress is allowed to the entire network.

  • TCP port 22 ingress (SSH) is allowed to the entire network.

  • Control plane TCP 6443 ingress (Kubernetes API) is allowed to the entire network.

  • Control plane TCP 22623 ingress (MCS) is allowed to the entire network.

Generating a key pair for cluster node SSH access

During an OKD installation, you can provide an SSH public key to the installation program. The key is passed to the Fedora CoreOS (FCOS) 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 FCOS 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.

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 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_ed25519, 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 OKD cluster that uses the Fedora cryptographic libraries that have been submitted to NIST for FIPS 140-2/140-3 Validation on only the x86_64, ppc64le, and s390x architectures, 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_ed25519.pub public key:

    $ cat ~/.ssh/id_ed25519.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_ed25519
    Example output
    Identity added: /home/<you>/<path>/<file_name> (<computer_name>)
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 the host you are using for installation.

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. Download your installation pull secret from Red Hat OpenShift Cluster Manager. 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 Red Hat OpenShift Cluster Manager 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.

    • 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.

Exporting the API key

You must set the API key you created as a global variable; the installation program ingests the variable during startup to set the API key.

Prerequisites
  • You have created either a user API key or service ID API key for your IBM Cloud® account.

Procedure
  • Export your API key for your account as a global variable:

    $ export IC_API_KEY=<api_key>

You must set the variable name exactly as specified; the installation program expects the variable name to be present during startup.

Creating the installation configuration file

You can customize the OKD cluster you install on IBM Cloud®.

Prerequisites
  • You have 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.

      When specifying the directory:

      • Verify that the directory has the execute permission. This permission is required to run Terraform binaries under the installation directory.

      • Use an empty directory. Some installation assets, such as bootstrap X.509 certificates, have short expiration intervals, therefore 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 ibmcloud as the platform to target.

      3. Select the region to deploy the cluster to.

      4. Select the base domain to deploy the cluster to. The base domain corresponds to the public DNS zone that you created for your cluster.

      5. Enter a descriptive name for your cluster.

  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.

Minimum resource requirements for cluster installation

Each cluster machine must meet the following minimum requirements:

Table 1. Minimum resource requirements
Machine Operating System vCPU Virtual RAM Storage Input/Output Per Second (IOPS)

Bootstrap

FCOS

4

16 GB

100 GB

300

Control plane

FCOS

4

16 GB

100 GB

300

Compute

FCOS

2

8 GB

100 GB

300

If an instance type for your platform meets the minimum requirements for cluster machines, it is supported to use in OKD.

Additional resources

Sample customized install-config.yaml file for IBM Cloud

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 then modify it.

apiVersion: v1
baseDomain: example.com (1)
controlPlane:  (2) (3)
  hyperthreading: Enabled (4)
  name: master
  platform:
    ibmcloud: {}
  replicas: 3
compute:  (2) (3)
- hyperthreading: Enabled (4)
  name: worker
  platform:
    ibmcloud: {}
  replicas: 3
metadata:
  name: test-cluster (1)
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14 (5)
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16
  networkType: OVNKubernetes (6)
  serviceNetwork:
  - 172.30.0.0/16
platform:
  ibmcloud:
    region: eu-gb (1)
    resourceGroupName: eu-gb-example-cluster-rg (7)
    networkResourceGroupName: eu-gb-example-existing-network-rg (8)
    vpcName: eu-gb-example-network-1 (9)
    controlPlaneSubnets: (10)
      - eu-gb-example-network-1-cp-eu-gb-1
      - eu-gb-example-network-1-cp-eu-gb-2
      - eu-gb-example-network-1-cp-eu-gb-3
    computeSubnets: (11)
      - eu-gb-example-network-1-compute-eu-gb-1
      - eu-gb-example-network-1-compute-eu-gb-2
      - eu-gb-example-network-1-compute-eu-gb-3
credentialsMode: Manual
publish: External
pullSecret: '{"auths": ...}' (1)
sshKey: ssh-ed25519 AAAA... (12)
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. Only one control plane pool is used.
4 Enables or disables simultaneous multithreading, also known as Hyper-Threading. 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 machine types, such as n1-standard-8, for your machines if you disable simultaneous multithreading.

5 The machine CIDR must contain the subnets for the compute machines and control plane machines.
6 The cluster network plugin to install. The supported values are OVNKubernetes and OpenShiftSDN. The default value is OVNKubernetes.
7 The name of an existing resource group. All installer-provisioned cluster resources are deployed to this resource group. If undefined, a new resource group is created for the cluster.
8 Specify the name of the resource group that contains the existing virtual private cloud (VPC). The existing VPC and subnets should be in this resource group. The cluster will be installed to this VPC.
9 Specify the name of an existing VPC.
10 Specify the name of the existing subnets to which to deploy the control plane machines. The subnets must belong to the VPC that you specified. Specify a subnet for each availability zone in the region.
11 Specify the name of the existing subnets to which to deploy the compute machines. The subnets must belong to the VPC that you specified. Specify a subnet for each availability zone in the region.
12 Optional: 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.

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 OKD 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.

    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 OpenStack, 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-----
    additionalTrustBundlePolicy: <policy_to_add_additionalTrustBundle> (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, 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 FCOS trust bundle. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the FCOS trust bundle.
    5 Optional: The policy to determine the configuration of the Proxy object to reference the user-ca-bundle config map in the trustedCA field. The allowed values are Proxyonly and Always. Use Proxyonly to reference the user-ca-bundle config map only when http/https proxy is configured. Use Always to always reference the user-ca-bundle config map. The default value is Proxyonly.

    The installation program does not support the proxy readinessEndpoints field.

    If the installer times out, restart and then complete the deployment by using the wait-for command of the installer. For example:

    $ ./openshift-install wait-for install-complete --log-level debug
  2. Save the file and reference it when installing OKD.

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.

Only the Proxy object named cluster is supported, and no additional proxies can be created.

Manually creating IAM

Installing the cluster requires that the Cloud Credential Operator (CCO) operate in manual mode. While the installation program configures the CCO for manual mode, you must specify the identity and access management secrets for you cloud provider.

You can use the Cloud Credential Operator (CCO) utility (ccoctl) to create the required IBM Cloud® resources.

Prerequisites
  • You have configured the ccoctl binary.

  • You have an existing install-config.yaml file.

Procedure
  1. Edit the install-config.yaml configuration file so that it contains the credentialsMode parameter set to Manual.

    Example install-config.yaml configuration file
    apiVersion: v1
    baseDomain: cluster1.example.com
    credentialsMode: Manual (1)
    compute:
    - architecture: amd64
      hyperthreading: Enabled
    1 This line is added to set the credentialsMode parameter to Manual.
  2. To generate the manifests, run the following command from the directory that contains the installation program:

    $ openshift-install create manifests --dir <installation_directory>
  3. From the directory that contains the installation program, set a $RELEASE_IMAGE variable with the release image from your installation file by running the following command:

    $ RELEASE_IMAGE=$(./openshift-install version | awk '/release image/ {print $3}')
  4. Extract the list of CredentialsRequest custom resources (CRs) from the OKD release image by running the following command:

    $ oc adm release extract \
      --from=$RELEASE_IMAGE \
      --credentials-requests \
      --included \(1)
      --install-config=<path_to_directory_with_installation_configuration>/install-config.yaml \(2)
      --to=<path_to_directory_for_credentials_requests> (3)
    1 The --included parameter includes only the manifests that your specific cluster configuration requires.
    2 Specify the location of the install-config.yaml file.
    3 Specify the path to the directory where you want to store the CredentialsRequest objects. If the specified directory does not exist, this command creates it.

    This command creates a YAML file for each CredentialsRequest object.

    Sample CredentialsRequest object
      apiVersion: cloudcredential.openshift.io/v1
      kind: CredentialsRequest
      metadata:
        labels:
          controller-tools.k8s.io: "1.0"
        name: openshift-image-registry-ibmcos
        namespace: openshift-cloud-credential-operator
      spec:
        secretRef:
          name: installer-cloud-credentials
          namespace: openshift-image-registry
        providerSpec:
          apiVersion: cloudcredential.openshift.io/v1
          kind: IBMCloudProviderSpec
          policies:
          - attributes:
            - name: serviceName
              value: cloud-object-storage
            roles:
            - crn:v1:bluemix:public:iam::::role:Viewer
            - crn:v1:bluemix:public:iam::::role:Operator
            - crn:v1:bluemix:public:iam::::role:Editor
            - crn:v1:bluemix:public:iam::::serviceRole:Reader
            - crn:v1:bluemix:public:iam::::serviceRole:Writer
          - attributes:
            - name: resourceType
              value: resource-group
            roles:
            - crn:v1:bluemix:public:iam::::role:Viewer
  5. Create the service ID for each credential request, assign the policies defined, create an API key, and generate the secret:

    $ ccoctl ibmcloud create-service-id \
      --credentials-requests-dir=<path_to_credential_requests_directory> \(1)
      --name=<cluster_name> \(2)
      --output-dir=<installation_directory> \(3)
      --resource-group-name=<resource_group_name> (4)
    1 Specify the directory containing the files for the component CredentialsRequest objects.
    2 Specify the name of the OKD cluster.
    3 Optional: Specify the directory in which you want the ccoctl utility to create objects. By default, the utility creates objects in the directory in which the commands are run.
    4 Optional: Specify the name of the resource group used for scoping the access policies.

    If your cluster uses Technology Preview features that are enabled by the TechPreviewNoUpgrade feature set, you must include the --enable-tech-preview parameter.

    If an incorrect resource group name is provided, the installation fails during the bootstrap phase. To find the correct resource group name, run the following command:

    $ grep resourceGroupName <installation_directory>/manifests/cluster-infrastructure-02-config.yml
Verification
  • Ensure that the appropriate secrets were generated in your cluster’s manifests directory.

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
  • You have configured an account with the cloud platform that hosts your cluster.

  • You have the OKD installation program and the pull secret for your cluster.

  • You have verified that the cloud provider account on your host has the correct permissions to deploy the cluster. An account with incorrect permissions causes the installation process to fail with an error message that displays the missing permissions.

Procedure
  • 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.
Verification

When the cluster deployment completes successfully:

  • The terminal displays directions for accessing your cluster, including a link to the web console and credentials for the kubeadmin user.

  • Credential information also outputs to <installation_directory>/.openshift_install.log.

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

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: "password"
INFO Time elapsed: 36m22s
  • 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.

  • It is recommended that you use Ignition config files within 12 hours after they are generated because the 24-hour certificate rotates from 16 to 22 hours after the cluster is installed. By using the Ignition config files within 12 hours, you can avoid installation failure if the certificate update runs during installation.

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 xvf <file>
  4. Place the oc binary in a directory that is on your PATH.

    To check your PATH, execute the following command:

    $ echo $PATH
Verification
  • 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 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
Verification
  • 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 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
Verification
  • 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 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
Additional resources
Additional resources