Chapter 4. Modifying a compute machine set You can modify a compute machine set, such as adding labels, changing the instance type, or changing block storage. Note If you need to scale a compute machine set without making other changes, see Manually scaling a compute machine set . 4.1. Modifying a compute machine set by using the CLI You can modify the configuration of a compute machine set, and then propagate the changes to the machines in your cluster by using the CLI. By updating the compute machine set configuration, you can enable features or change the properties of the machines it creates. 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 Your OpenShift Container Platform cluster uses the Machine API. You are logged in to the cluster as an administrator by using the OpenShift CLI ( oc ). Procedure List the compute machine sets in your cluster by running the following command: USD 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 Edit a compute machine set by running the following command: USD oc edit machinesets.machine.openshift.io <machine_set_name> \ -n openshift-machine-api Note the value of the spec.replicas field, because you need it when scaling the machine set to apply the changes. apiVersion: machine.openshift.io/v1beta1 kind: MachineSet metadata: name: <machine_set_name> namespace: openshift-machine-api spec: replicas: 2 1 # ... 1 The examples in this procedure show a compute machine set that has a replicas value of 2 . Update the compute machine set CR with the configuration options that you want and save your changes. List the machines that are managed by the updated compute machine set by running the following command: USD 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 For each machine that is managed by the updated compute machine set, set the delete annotation by running the following command: USD oc annotate machine.machine.openshift.io/<machine_name_original_1> \ -n openshift-machine-api \ machine.openshift.io/delete-machine="true" To create replacement machines with the new configuration, scale the compute machine set to twice the number of replicas by running the following command: USD oc scale --replicas=4 \ 1 machineset.machine.openshift.io <machine_set_name> \ -n openshift-machine-api 1 The original example value of 2 is doubled to 4 . List the machines that are managed by the updated compute machine set by running the following command: USD 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 When the new machines are in the Running phase, you can scale the compute machine set to the original number of replicas. 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: USD oc scale --replicas=2 \ 1 machineset.machine.openshift.io <machine_set_name> \ -n openshift-machine-api 1 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: USD oc describe machine.machine.openshift.io <machine_name_updated_1> \ -n openshift-machine-api 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: USD 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 Additional resources Lifecycle hooks for the machine deletion phase Scaling a compute machine set manually Controlling pod placement using the scheduler

Commands:
oc get machinesets.machine.openshift.io -n openshift-machine-api
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
oc edit machinesets.machine.openshift.io <machine_set_name> -n openshift-machine-api
apiVersion: machine.openshift.io/v1beta1 kind: MachineSet metadata: name: <machine_set_name> namespace: openshift-machine-api spec: replicas: 2 1
oc get machines.machine.openshift.io -n openshift-machine-api -l machine.openshift.io/cluster-api-machineset=<machine_set_name>
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
oc annotate machine.machine.openshift.io/<machine_name_original_1> -n openshift-machine-api machine.openshift.io/delete-machine="true"
oc scale --replicas=4 \ 1 machineset.machine.openshift.io <machine_set_name> -n openshift-machine-api
oc get machines.machine.openshift.io -n openshift-machine-api -l machine.openshift.io/cluster-api-machineset=<machine_set_name>
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
oc scale --replicas=2 \ 1 machineset.machine.openshift.io <machine_set_name> -n openshift-machine-api
oc describe machine.machine.openshift.io <machine_name_updated_1> -n openshift-machine-api
oc get machines.machine.openshift.io -n openshift-machine-api -l machine.openshift.io/cluster-api-machineset=<machine_set_name>
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
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