You can make changes to a MachineSet, such as adding labels, changing the instance type, or changing block storage.

If you need to scale a MachineSet without making other changes, see Manually scaling a MachineSet.

Modifying a machine set

To make changes to a machine set, edit the MachineSet YAML. Then, remove all machines associated with the machine set by deleting each machine or scaling down the machine set to 0 replicas. Then, scale the replicas back to the desired number. Changes you make to a machine set do not affect existing machines.

If you need to scale a machine set without making other changes, you do not need to delete the machines.

By default, the OpenShift Container Platform router pods are deployed on workers. Because the router is required to access some cluster resources, including the web console, do not scale the worker machine set to 0 unless you first relocate the router pods.

Prerequisites
  • Install an OpenShift Container Platform cluster and the oc command line.

  • Log in to oc as a user with cluster-admin permission.

Procedure
  1. Edit the machine set:

    $ oc edit machineset <machineset> -n openshift-machine-api
  2. Scale down the machine set to 0:

    $ oc scale --replicas=0 machineset <machineset> -n openshift-machine-api

    Or:

    $ oc edit machineset <machineset> -n openshift-machine-api

    Wait for the machines to be removed.

  3. Scale up the machine set as needed:

    $ oc scale --replicas=2 machineset <machineset> -n openshift-machine-api

    Or:

    $ oc edit machineset <machineset> -n openshift-machine-api

    Wait for the machines to start. The new machines contain changes you made to the machine set.