Red Hat OpenShift Container Platform

Create a compute machine set

To dynamically manage machine compute resources, you can create your own compute machine sets in addition to the compute machine sets created by the installation program. Use the Red Hat OpenShift Container Platform CLI to automate node provisioning.

Prerequisites

Deploy an Red Hat OpenShift Container Platform cluster.
Install the OpenShift CLI (oc).
Log in to oc as a user with cluster-admin permission.

Procedure

Create a new YAML file that contains the compute machine set custom resource (CR) sample and is named <file_name>.yaml.

Ensure that you set the <clusterID> and <role> parameter values.

Optional: If you are not sure which value to set for a specific field, you can check an existing compute machine set from your cluster.

To list the compute machine sets in your cluster, run the following command:

$ oc get machinesets -n openshift-machine-api

The following is example output:

NAME                                DESIRED   CURRENT   READY   AVAILABLE   AGE
agl030519-vplxk-worker-us-east-1a   1         1         1       1           55m
agl030519-vplxk-worker-us-east-1b   1         1         1       1           55m
agl030519-vplxk-worker-us-east-1c   1         1         1       1           55m
agl030519-vplxk-worker-us-east-1d   0         0                             55m
agl030519-vplxk-worker-us-east-1e   0         0                             55m
agl030519-vplxk-worker-us-east-1f   0         0                             55m

To view values of a specific compute machine set custom resource (CR), run the following command:

$ oc get machineset <machineset_name> \
  -n openshift-machine-api -o yaml

The following is example output:

apiVersion: machine.openshift.io/v1beta1
kind: MachineSet
metadata:
  labels:
    machine.openshift.io/cluster-api-cluster: <infrastructure_id>
  name: <infrastructure_id>-<role>
  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>-<role>
  template:
    metadata:
      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>-<role>
    spec:
      providerSpec:
        ...

where:

metadata.labels.machine.openshift.io/cluster-api-cluster

Specifies the cluster infrastructure ID.

metadata.labels.name

Specifies a default node label.

For clusters that have user-provisioned infrastructure, a compute machine set can only create worker and infra type machines.

spec.template.metadata.spec.providerSpec

Specifies the values of the compute machine set CR. The values are platform-specific. For more information about <providerSpec> parameters in the CR, see the sample compute machine set CR configuration for your provider.

Create a MachineSet CR by running the following command:
```
$ oc create -f <file_name>.yaml
```
If you need compute machine sets in other availability zones, repeat this process to create more compute machine sets.

Verification

View the list of compute machine sets by running the following command:

$ oc get machineset -n openshift-machine-api

The following is example output:

NAME                                DESIRED   CURRENT   READY   AVAILABLE   AGE
agl030519-vplxk-infra-us-east-1a    1         1         1       1           11m
agl030519-vplxk-worker-us-east-1a   1         1         1       1           55m
agl030519-vplxk-worker-us-east-1b   1         1         1       1           55m
agl030519-vplxk-worker-us-east-1c   1         1         1       1           55m
agl030519-vplxk-worker-us-east-1d   0         0                             55m
agl030519-vplxk-worker-us-east-1e   0         0                             55m
agl030519-vplxk-worker-us-east-1f   0         0                             55m

When the new compute machine set is available, the DESIRED and CURRENT values match. If the compute machine set is not available, wait a few minutes and run the command again.