Switch over a PostgreSQL cluster

You can initiate a switchover for a PostgreSQL Replication Cluster by executing the kbcli or kubectl command. Then KubeBlocks modifies 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 postgresql -o yaml
  >
  probes:
    roleProbe:
      failureThreshold: 2
      periodSeconds: 1
      timeoutSeconds: 1

Initiate the switchover

You can switch over a secondary of a PostgreSQL Replication Cluster to the primary role, and the former primary instance to a secondary.

• Switchover with no primary instance specified

  kbcli cluster promote pg-cluster

• Switchover with a specified new primary instance

  kbcli cluster promote pg-cluster --instance='pg-cluster-postgresql-2'

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

  kbcli cluster promote pg-cluster --instance='pg-cluster-postgresql-2' --components='postgresql'

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.