Switch over an ApeCloud MySQL cluster

You can initiate a switchover for an ApeCloud MySQL RaftGroup by executing the kbcli or kubectl command. Then KubeBlocks switches the instance roles.

Before you start

• Make sure the cluster is running normally.

• Check whether the following role probe parameters exist to verify whether the role probe is enabled.

  kubectl get cd apecloud-mysql -o yaml
  >
  probes:
    roleProbe:
      failureThreshold: 2
      periodSeconds: 1
      timeoutSeconds: 1

Initiate the switchover

You can switch over a follower of an ApeCloud MySQL RaftGroup to the leader role, and the former leader instance to a follower.

• Initiate a switchover with no leader instance specified.

  kbcli cluster promote mycluster

• Initiate a switchover with a specified new leader instance.

  kbcli cluster promote mycluster --instance='mycluster-mysql-2'

• If there are multiple components, you can use --components to specify a component.

  kbcli cluster promote mycluster --instance='mycluster-mysql-2' --components='apecloud-mysql'

Verify the switchover

Check the instance status to verify whether the switchover is performed successfully.

kbcli cluster list-instances

Handle an exception

If an error occurs, refer to Handle an exception to troubleshoot the operation.