On the High Availability screen, you can swap the roles of the SMS HA cluster nodes to promote the passive SMS to the active SMS, and reconfigure the active SMS to the passive SMS.
This process can take several minutes, during which time the SMS HA cluster is re-synchronized,
nodes are restarted, and the SMS client is temporarily disconnected to re-establish
the SMS HA cluster to a fully functional active-passive state. The operational state
of the cluster is shown as Configured for the active SMS server and for the passive
SMS server until the synchronization process finishes.