Apply MCS to an existing cluster

You can turn on MCS for the already-existing non-MCS cluster. To do this:

• Restart the Operator after editing the multiCluster subsection keys and applying deploy/cr.yaml. Find the Operator’s Pod name in the output of the kubectl get pods command (it will be something like percona-server-mongodb-operator-d859b69b6-t44vk) and delete it as follows:

  kubectl delete percona-server-mongodb-operator-d859b69b6-t44vk
  

• If you are enabling MCS for a running cluster after upgrading from the Operator version 1.11.0 or below, you need rotating multi-domain (SAN) certificates. Do this by pausing the cluster and deleting TLS Secrets.

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Last update: 2025-10-21