// Module included in the following assemblies:
//
// * machine_management/cpmso-getting-started.adoc

:_mod-docs-content-type: PROCEDURE
[id="cpmso-activating_{context}"]
= Activating the control plane machine set custom resource

To use the control plane machine set, you must ensure that a `ControlPlaneMachineSet` custom resource (CR) with the correct settings for your cluster exists. On a cluster with a generated CR, you must verify that the configuration in the CR is correct for your cluster and activate it.

[NOTE]
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For more information about the parameters in the CR, see "Control plane machine set configuration".
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.Procedure

. View the configuration of the CR by running the following command:
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[source,terminal]
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$ oc --namespace openshift-machine-api edit controlplanemachineset.machine.openshift.io cluster
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. Change the values of any fields that are incorrect for your cluster configuration.

. When the configuration is correct, activate the CR by setting the `.spec.state` field to `Active` and saving your changes.
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[IMPORTANT]
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To activate the CR, you must change the `.spec.state` field to `Active` in the same `oc edit` session that you use to update the CR configuration. If the CR is saved with the state left as `Inactive`, the control plane machine set generator resets the CR to its original settings.
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