Modifying a compute machine set

To add labels, change the instance type, change block storage, or make other changes, you can modify a compute machine set.

Note

If you need to scale a compute machine set without making other changes, see "Manually scaling a compute machine set".

Modify a compute machine set by using the CLI

To enable features or change the properties of machines, you can modify the configuration of a compute machine set using the CLI. You can then propagate the changes to the machines in your cluster.

When you modify a compute machine set, your changes only apply to compute machines that are created after you save the updated MachineSet custom resource (CR). The changes do not affect existing machines.

Note

Changes made in the underlying cloud provider are not reflected in the Machine or MachineSet CRs. To adjust instance configuration in cluster-managed infrastructure, use the cluster-side resources.

You can replace the existing machines with new ones that reflect the updated configuration by scaling the compute machine set to create twice the number of replicas and then scaling it down to the original number of replicas.

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

Note

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

The output examples in this procedure use the values for an AWS cluster.

Prerequisites

tag:CAPI[][]

• Your OpenShift Container Platform cluster uses the Cluster API. end:CAPI[][] tag:MAPI[][]
• Your OpenShift Container Platform cluster uses the Machine API. end:MAPI[][]
• You are logged in to the cluster as an administrator by using the OpenShift CLI (oc).

Procedure

1. List the compute machine sets in your cluster by running the following command:

   tag:CAPI[][]

   $ oc get machinesets.cluster.x-k8s.io -n openshift-cluster-api
   

   Example output

   NAME                          CLUSTER             REPLICAS   READY   AVAILABLE   AGE   VERSION
   <compute_machine_set_name_1>  <cluster_name>      1          1       1           26m
   <compute_machine_set_name_2>  <cluster_name>      1          1       1           26m
   

   end:CAPI[][] tag:MAPI[][]

   $ oc get machinesets.machine.openshift.io -n openshift-machine-api
   

   Example output

   NAME                           DESIRED   CURRENT   READY   AVAILABLE   AGE
   <compute_machine_set_name_1>   1         1         1       1           55m
   <compute_machine_set_name_2>   1         1         1       1           55m
   

   end:MAPI[][]

2. Edit a compute machine set by running the following command:

   tag:CAPI[][]

   $ oc edit machinesets.cluster.x-k8s.io <machine_set_name> \
     -n openshift-cluster-api
   

   end:CAPI[][] tag:MAPI[][]

   $ oc edit machinesets.machine.openshift.io <machine_set_name> \
     -n openshift-machine-api
   

   end:MAPI[][]

3. Note the value of the spec.replicas field, because you need it when scaling the machine set to apply the changes.

   #tag::CAPI[]
   apiVersion: cluster.x-k8s.io/v1beta1
   #end::CAPI[]
   #tag::MAPI[]
   apiVersion: machine.openshift.io/v1beta1
   #end::MAPI[]
   kind: MachineSet
   metadata:
     name: <machine_set_name>
   #tag::CAPI[]
     namespace: openshift-cluster-api
   #end::CAPI[]
   #tag::MAPI[]
     namespace: openshift-machine-api
   #end::MAPI[]
   spec:
     replicas: 2
   # ...
   

   The examples in this procedure show a compute machine set that has a replicas value of 2.

4. Update the compute machine set CR with the configuration options that you want and save your changes.

5. List the machines that are managed by the updated compute machine set by running the following command:

   tag:CAPI[][]

   $ oc get machines.cluster.x-k8s.io \
     -n openshift-cluster-api \
     -l cluster.x-k8s.io/set-name=<machine_set_name>
   

   Example output for an AWS cluster

   NAME                        CLUSTER          NODENAME                                    PROVIDERID                              PHASE           AGE     VERSION
   <machine_name_original_1>   <cluster_name>   <original_1_ip>.<region>.compute.internal   aws:///us-east-2a/i-04e7b2cbd61fd2075   Running         4h
   <machine_name_original_2>   <cluster_name>   <original_2_ip>.<region>.compute.internal   aws:///us-east-2a/i-04e7b2cbd61fd2075   Running         4h
   

   end:CAPI[][] tag:MAPI[][]

   $ oc get machines.machine.openshift.io \
     -n openshift-machine-api \
     -l machine.openshift.io/cluster-api-machineset=<machine_set_name>
   

   Example output for an AWS cluster

   NAME                        PHASE     TYPE         REGION      ZONE         AGE
   <machine_name_original_1>   Running   m6i.xlarge   us-west-1   us-west-1a   4h
   <machine_name_original_2>   Running   m6i.xlarge   us-west-1   us-west-1a   4h
   

   end:MAPI[][]

6. For each machine that is managed by the updated compute machine set, set the delete annotation by running the following command:

   tag:CAPI[][]

   $ oc annotate machines.cluster.x-k8s.io/<machine_name_original_1> \
     -n openshift-cluster-api \
     cluster.x-k8s.io/delete-machine="true"
   

   end:CAPI[][] tag:MAPI[][]

   $ oc annotate machine.machine.openshift.io/<machine_name_original_1> \
     -n openshift-machine-api \
     machine.openshift.io/delete-machine="true"
   

   end:MAPI[][]

7. To create replacement machines with the new configuration, scale the compute machine set to twice the number of replicas by running the following command:

   tag:CAPI[][]

   $ oc scale --replicas=4 \
     machinesets.cluster.x-k8s.io <machine_set_name> \
     -n openshift-cluster-api
   

   end:CAPI[][] tag:MAPI[][]

   $ oc scale --replicas=4 \
     machineset.machine.openshift.io <machine_set_name> \
     -n openshift-machine-api
   

   end:MAPI[][]

   The original example value of 2 is doubled to 4.

8. List the machines that are managed by the updated compute machine set by running the following command:

   tag:CAPI[][]

   $ oc get machines.cluster.x-k8s.io \
     -n openshift-cluster-api \
     -l cluster.x-k8s.io/set-name=<machine_set_name>
   

   Example output for an AWS cluster

   NAME                        CLUSTER          NODENAME                                    PROVIDERID                              PHASE           AGE     VERSION
   <machine_name_original_1>   <cluster_name>   <original_1_ip>.<region>.compute.internal   aws:///us-east-2a/i-04e7b2cbd61fd2075   Running         4h
   <machine_name_original_2>   <cluster_name>   <original_2_ip>.<region>.compute.internal   aws:///us-east-2a/i-04e7b2cbd61fd2075   Running         4h
   <machine_name_updated_1>    <cluster_name>   <updated_1_ip>.<region>.compute.internal    aws:///us-east-2a/i-04e7b2cbd61fd2075   Provisioned     55s
   <machine_name_updated_2>    <cluster_name>   <updated_2_ip>.<region>.compute.internal    aws:///us-east-2a/i-04e7b2cbd61fd2075   Provisioning    55s
   

   end:CAPI[][] tag:MAPI[][]

   $ oc get machines.machine.openshift.io \
     -n openshift-machine-api \
     -l machine.openshift.io/cluster-api-machineset=<machine_set_name>
   

   Example output for an AWS cluster

   NAME                        PHASE          TYPE         REGION      ZONE         AGE
   <machine_name_original_1>   Running        m6i.xlarge   us-west-1   us-west-1a   4h
   <machine_name_original_2>   Running        m6i.xlarge   us-west-1   us-west-1a   4h
   <machine_name_updated_1>    Provisioned    m6i.xlarge   us-west-1   us-west-1a   55s
   <machine_name_updated_2>    Provisioning   m6i.xlarge   us-west-1   us-west-1a   55s
   

   end:MAPI[][]

   When the new machines are in the Running phase, you can scale the compute machine set to the original number of replicas.

9. To remove the machines that were created with the old configuration, scale the compute machine set to the original number of replicas by running the following command:

   tag:CAPI[][]

   $ oc scale --replicas=2 \
     machinesets.cluster.x-k8s.io <machine_set_name> \
     -n openshift-cluster-api
   

   end:CAPI[][] tag:MAPI[][]

   $ oc scale --replicas=2 \
     machineset.machine.openshift.io <machine_set_name> \
     -n openshift-machine-api
   

   end:MAPI[][]

   The replicas parameter is set to the original example value of 2.

Verification

• To verify that a machine created by the updated machine set has the correct configuration, examine the relevant fields in the CR for one of the new machines by running the following command:

  tag:CAPI[][]

  $ oc describe machines.cluster.x-k8s.io <machine_name_updated_1> \
    -n openshift-cluster-api
  

  end:CAPI[][] tag:MAPI[][]

  $ oc describe machine.machine.openshift.io <machine_name_updated_1> \
    -n openshift-machine-api
  

  end:MAPI[][]

• To verify that the compute machines without the updated configuration are deleted, list the machines that are managed by the updated compute machine set by running the following command:

  tag:CAPI[][]

  $ oc get machines.cluster.x-k8s.io \
    -n openshift-cluster-api \
    cluster.x-k8s.io/set-name=<machine_set_name>
  

  Example output while deletion is in progress for an AWS cluster

  NAME                        CLUSTER          NODENAME                                    PROVIDERID                              PHASE      AGE     VERSION
  <machine_name_original_1>   <cluster_name>   <original_1_ip>.<region>.compute.internal   aws:///us-east-2a/i-04e7b2cbd61fd2075   Running    18m
  <machine_name_original_2>   <cluster_name>   <original_2_ip>.<region>.compute.internal   aws:///us-east-2a/i-04e7b2cbd61fd2075   Running    18m
  <machine_name_updated_1>    <cluster_name>   <updated_1_ip>.<region>.compute.internal    aws:///us-east-2a/i-04e7b2cbd61fd2075   Running    18m
  <machine_name_updated_2>    <cluster_name>   <updated_2_ip>.<region>.compute.internal    aws:///us-east-2a/i-04e7b2cbd61fd2075   Running    18m
  

  Example output when deletion is complete for an AWS cluster

  NAME                        CLUSTER          NODENAME                                    PROVIDERID                              PHASE      AGE     VERSION
  <machine_name_updated_1>    <cluster_name>   <updated_1_ip>.<region>.compute.internal    aws:///us-east-2a/i-04e7b2cbd61fd2075   Running    18m
  <machine_name_updated_2>    <cluster_name>   <updated_2_ip>.<region>.compute.internal    aws:///us-east-2a/i-04e7b2cbd61fd2075   Running    18m
  

  end:CAPI[][] tag:MAPI[][]

  $ oc get machines.machine.openshift.io \
    -n openshift-machine-api \
    -l machine.openshift.io/cluster-api-machineset=<machine_set_name>
  

  Example output while deletion is in progress for an AWS cluster

  NAME                        PHASE           TYPE         REGION      ZONE         AGE
  <machine_name_original_1>   Deleting        m6i.xlarge   us-west-1   us-west-1a   4h
  <machine_name_original_2>   Deleting        m6i.xlarge   us-west-1   us-west-1a   4h
  <machine_name_updated_1>    Running         m6i.xlarge   us-west-1   us-west-1a   5m41s
  <machine_name_updated_2>    Running         m6i.xlarge   us-west-1   us-west-1a   5m41s
  

  Example output when deletion is complete for an AWS cluster

  NAME                        PHASE           TYPE         REGION      ZONE         AGE
  <machine_name_updated_1>    Running         m6i.xlarge   us-west-1   us-west-1a   6m30s
  <machine_name_updated_2>    Running         m6i.xlarge   us-west-1   us-west-1a   6m30s
  

  end:MAPI[][]

Additional resources

• Lifecycle hooks for the machine deletion phase
• Manually scaling a compute machine set
• Controlling pod placement using the scheduler