Creating a cluster with multi-architecture compute machines on Google Cloud¶

To deploy a cluster on Google Cloud with multi-architecture compute machines, you must first create a single-architecture installer-provisioned cluster that uses the multi-architecture installer binary.

You can also migrate your current cluster with single-architecture compute machines to a cluster with multi-architecture compute machines. After creating a multi-architecture cluster, you can add nodes with different architectures to the cluster.

Adding a multi-architecture compute machine set to your Google Cloud cluster¶

After creating a multi-architecture cluster, you can add nodes with different architectures.

You can add multi-architecture compute machines to a multi-architecture cluster in the following ways:

• Adding 64-bit x86 compute machines to a cluster that uses 64-bit ARM control plane machines and already includes 64-bit ARM compute machines. In this case, 64-bit x86 is considered the secondary architecture.
• Adding 64-bit ARM compute machines to a cluster that uses 64-bit x86 control plane machines and already includes 64-bit x86 compute machines. In this case, 64-bit ARM is considered the secondary architecture.

Prerequisites

• You installed the OpenShift CLI (oc).
• You used the installation program to create a 64-bit ARM or 64-bit x86 single-architecture cluster with the multi-architecture installer binary.

Procedure

1. Log in to the OpenShift CLI (oc).
2. Create a YAML file and add the configuration to create a compute machine set to control the 64-bit ARM or 64-bit x86 compute nodes in your cluster.
   Example MachineSet object for a Google Cloud 64-bit ARM or 64-bit x86 compute node

   apiVersion: machine.openshift.io/v1beta1
   kind: MachineSet
   metadata:
     labels:
       machine.openshift.io/cluster-api-cluster: <infrastructure_id>
     name: <infrastructure_id>-w-a
     namespace: openshift-machine-api
   spec:
     replicas: 1
     selector:
       matchLabels:
         machine.openshift.io/cluster-api-cluster: <infrastructure_id>
         machine.openshift.io/cluster-api-machineset: <infrastructure_id>-w-a
     template:
       metadata:
         creationTimestamp: null
         labels:
           machine.openshift.io/cluster-api-cluster: <infrastructure_id>
           machine.openshift.io/cluster-api-machine-role: <role>
           machine.openshift.io/cluster-api-machine-type: <role>
           machine.openshift.io/cluster-api-machineset: <infrastructure_id>-w-a
       spec:
         metadata:
           labels:
             node-role.kubernetes.io/<role>: ""
         providerSpec:
           value:
             apiVersion: gcpprovider.openshift.io/v1beta1
             canIPForward: false
             credentialsSecret:
               name: gcp-cloud-credentials
             deletionProtection: false
             disks:
             - autoDelete: true
               boot: true
               image: <path_to_image>
               labels: null
               sizeGb: 128
               type: pd-ssd
             gcpMetadata:
             - key: <custom_metadata_key>
               value: <custom_metadata_value>
             kind: GCPMachineProviderSpec
             machineType: n1-standard-4
             metadata:
               creationTimestamp: null
             networkInterfaces:
             - network: <infrastructure_id>-network
               subnetwork: <infrastructure_id>-worker-subnet
             projectID: <project_name>
             region: us-central1
             serviceAccounts:
             - email: <infrastructure_id>-w@<project_name>.iam.gserviceaccount.com
               scopes:
               - https://www.googleapis.com/auth/cloud-platform
             tags:
               - <infrastructure_id>-worker
             userDataSecret:
               name: worker-user-data
             zone: us-central1-a

   where:

   <infrastructure_id>

   Specifies the infrastructure ID that is based on the cluster ID that you set when you provisioned the cluster. You can obtain the infrastructure ID by running the following command:

   terminal

   $ oc get -o jsonpath='{.status.infrastructureName}{"\n"}' infrastructure cluster

   <role>

   Specifies the role node label to add.

   <path_to_image>

   Specifies the path to the image that is used in current compute machine sets. You need the project and image name for your path to image. To access the project and image name, run the following command:

   terminal

   $ oc get configmap/coreos-bootimages \
     -n openshift-machine-config-operator \
     -o jsonpath='{.data.stream}' | jq \
     -r '.architectures.aarch64.images.gcp'

   Example output

     "gcp": {
       "release": "415.92.202309142014-0",
       "project": "rhcos-cloud",
       "name": "rhcos-415-92-202309142014-0-gcp-aarch64"
     }

   Use the project and name parameters from the output to create the path to image field in your machine set. The path to the image should follow the following format:

   terminal

   $ projects/<project>/global/images/<image_name>

   gcpMetadata

   Optional parameter. Specifies custom metadata in the form of a key:value pair. For example use cases, see "Setting custom metadata".

   machineType

   Specifies a machine type that aligns with the CPU architecture of the chosen OS image. For more information, see "Tested instance types for Google Cloud on 64-bit ARM infrastructures".

   projectID

   Specifies the name of the Google Cloud project that you use for your cluster.

   region

   Specifies the region. For example, us-central1. Ensure that the zone you select has machines with the required architecture.

3. Create the compute machine set by running the following command:
   terminal

   $ oc create -f <file_name>

   • Replace <file_name> with the name of the YAML file with compute machine set configuration. For example: gcp-arm64-machine-set-0.yaml, or gcp-amd64-machine-set-0.yaml.

Verification

1. Verify that the new machines are running by running the following command:
   terminal

   $ oc get machineset -n openshift-machine-api

   The output must include the machine set that you created.

   Example output

   NAME                                                DESIRED  CURRENT  READY  AVAILABLE  AGE
   <infrastructure_id>-gcp-machine-set-0                   2        2      2          2  10m

2. You can check if the nodes are ready and schedulable by running the following command:
   terminal

   $ oc get nodes