Installing a cluster on IBM Cloud VPC with network customizations

In OKD version 4.11, you can install a cluster with a customized network configuration on infrastructure that the installation program provisions on IBM Cloud VPC. By customizing your network configuration, your cluster can coexist with existing IP address allocations in your environment and integrate with existing MTU and VXLAN configurations. To customize the installation, you modify parameters in the install-config.yaml file before you install the cluster.

You must set most of the network configuration parameters during installation, and you can modify only kubeProxy configuration parameters in a running cluster.

Prerequisites

• You reviewed details about the OKD installation and update processes.

• You read the documentation on selecting a cluster installation method and preparing it for users.

• You configured an IBM Cloud VPC account to host the cluster.

• If you use a firewall, you configured it to allow the sites that your cluster requires access to.

• You configured the ccoctl utility before you installed the cluster. For more information, see Configuring IAM for IBM Cloud VPC.

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.

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 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_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 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. Download your installation pull secret from the 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 the 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.

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

   • Red Hat Operators are not available.

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

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

Exporting the IBM Cloud VPC API key

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

Prerequisties

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

Procedure

• Export your IBM Cloud VPC API key as a global variable:

  $ export IC_API_KEY=<api_key>

Creating the installation configuration file

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

Prerequisites

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

• Obtain service principal permissions at the subscription level.

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.

      6. Paste the pull secret from the Red Hat OpenShift Cluster Manager. This field is optional.

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

2. 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.

Required configuration parameters

Required installation configuration parameters are described in the following table:

Network configuration parameters

You can customize your installation configuration based on the requirements of your existing network infrastructure. For example, you can expand the IP address block for the cluster network or provide different IP address blocks than the defaults.

If you use the OVN-Kubernetes cluster network provider, both IPv4 and IPv6 address families are supported.

If you use the OpenShift SDN cluster network provider, only the IPv4 address family is supported.

If you configure your cluster to use both IP address families, review the following requirements:

• Both IP families must use the same network interface for the default gateway.

• Both IP families must have the default gateway.

• You must specify IPv4 and IPv6 addresses in the same order for all network configuration parameters. For example, in the following configuration IPv4 addresses are listed before IPv6 addresses.

  networking:
    clusterNetwork:
    - cidr: 10.128.0.0/14
      hostPrefix: 23
    - cidr: fd01::/48
      hostPrefix: 64
    serviceNetwork:
    - 172.30.0.0/16
    - fd00:172:16::/112

networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  - cidr: fd01::/48
    hostPrefix: 64

networking:
  serviceNetwork:
   - 172.30.0.0/16
   - fd02::/112

networking:
  machineNetwork:
  - cidr: 10.0.0.0/16

Optional configuration parameters

Optional installation configuration parameters are described in the following table:

sshKey:
  <key1>
  <key2>
  <key3>

Additional IBM Cloud VPC configuration parameters

Additional IBM Cloud VPC configuration parameters are described in the following table:

1. Whether you define an existing resource group, or if the installer creates one, determines how the resource group is treated when the cluster is uninstalled. If you define a resource group, the installer removes all of the installer-provisioned resources, but leaves the resource group alone; if a resource group is created as part of the installation, the installer removes all of the installer provisioned resources and the resource group.

2. To determine which profile best meets your needs, see Instance Profiles in the IBM documentation.

Sample customized install-config.yaml file for IBM Cloud VPC

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.

apiVersion: v1
baseDomain: example.com (1)
controlPlane:  (2) (3)
  hyperthreading: Enabled (4)
  name: master
  platform:
    ibm-cloud: {}
  replicas: 3
compute:  (2) (3)
- hyperthreading: Enabled (4)
  name: worker
  platform:
    ibmcloud: {}
  replicas: 3
metadata:
  name: test-cluster (1)
networking: (2)
  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:
  ibmcloud:
    region: us-south (1)
credentialsMode: Manual
publish: External
pullSecret: '{"auths": ...}' (1)
sshKey: ssh-ed25519 AAAA... (5)
capabilities:
  baselineCapabilitySet: None
  additionalEnabledCapabilities:
  - openshift-samples

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-----

   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 that contains one or more additional CA certificates that are required for proxying HTTPS connections. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges these contents with the Fedora CoreOS (FCOS) trust bundle, and this config map is referenced in the trustedCA field of the Proxy object. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the FCOS trust bundle.

   The installation program does not support the proxy readinessEndpoints field.

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.

Manually creating IAM for IBM Cloud VPC

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 VPC 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, obtain the OKD release image that your openshift-install binary is built to use:

   $ RELEASE_IMAGE=$(./openshift-install version | awk '/release image/ {print $3}')

4. Extract the CredentialsRequest objects from the OKD release image:

   $ oc adm release extract --cloud=ibmcloud --credentials-requests $RELEASE_IMAGE \
       --to=<path_to_credential_requests_directory> (1)

   1	The directory where the credential requests will be stored.

   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 in IBM Cloud VPC, and generate the secret:

   $ ccoctl ibmcloud create-service-id \
       --credentials-requests-dir <path_to_store_credential_request_templates> \ (1)
       --name <cluster_name> \ (2)
       --output-dir <installation_directory> \
       --resource-group-name <resource_group_name> (3)

   1	The directory where the credential requests are stored.
   2	The name of the OKD cluster.
   3	Optional: 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.

Network configuration phases

There are two phases prior to OKD installation where you can customize the network configuration.

Phase 1

You can customize the following network-related fields in the install-config.yaml file before you create the manifest files:

• networking.networkType

• networking.clusterNetwork

• networking.serviceNetwork

• networking.machineNetwork

  For more information on these fields, refer to Installation configuration parameters.

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

Phase 2

After creating the manifest files by running openshift-install create manifests, you can define a customized Cluster Network Operator manifest with only the fields you want to modify. You can use the manifest to specify advanced network configuration.

You cannot override the values specified in phase 1 in the install-config.yaml file during phase 2. However, you can further customize the cluster network provider during phase 2.

Specifying advanced network configuration

You can use advanced network configuration for your cluster network provider to integrate your cluster into your existing network environment. You can specify advanced network configuration only before you install the cluster.

Prerequisites

• You have created the install-config.yaml file and completed any modifications to it.

Procedure

1. Change to the directory that contains the installation program and create the manifests:

   $ ./openshift-install create manifests --dir <installation_directory> (1)

   1	<installation_directory> specifies the name of the directory that contains the install-config.yaml file for your cluster.

2. Create a stub manifest file for the advanced network configuration that is named cluster-network-03-config.yml in the <installation_directory>/manifests/ directory:

   apiVersion: operator.openshift.io/v1
   kind: Network
   metadata:
     name: cluster
   spec:

3. Specify the advanced network configuration for your cluster in the cluster-network-03-config.yml file, such as in the following example:

   Specify a different VXLAN port for the OpenShift SDN network provider

   apiVersion: operator.openshift.io/v1
   kind: Network
   metadata:
     name: cluster
   spec:
     defaultNetwork:
       openshiftSDNConfig:
         vxlanPort: 4800

4. Optional: Back up the manifests/cluster-network-03-config.yml file. The installation program consumes the manifests/ directory when you create the Ignition config files.

Cluster Network Operator configuration

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

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

clusterNetwork

IP address pools from which pod IP addresses are allocated.

serviceNetwork

IP address pool for services.

defaultNetwork.type

Cluster network provider, such as OpenShift SDN or OVN-Kubernetes.

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

Cluster Network Operator configuration object

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

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

spec:
  serviceNetwork:
  - 172.30.0.0/14

defaultNetwork object configuration

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

Configuration for the OpenShift SDN CNI cluster network provider

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

Example OpenShift SDN configuration

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

Configuration for the OVN-Kubernetes CNI cluster network provider

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

While migrating egress traffic, you can expect some disruption to workloads and service traffic until the Cluster Network Operator (CNO) successfully rolls out the changes.

Example OVN-Kubernetes configuration with IPSec enabled

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

kubeProxyConfig object configuration

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

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

Deploying the cluster

You can install OKD on a compatible cloud platform.

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

+

$ ./openshift-install create cluster --dir <installation_directory> \ (1)
    --log-level=info (2)

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.

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

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.

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 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

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

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

• Accessing the web console

Additional resources

• About remote health monitoring

Next steps

• Customize your cluster.

• If necessary, you can opt out of remote health reporting.