Switching the source system from the primary node to a backup node within a cluster configuration is a simple process. The default planned switch procedure performs the following activities:
The status of the application group changes to *SWTPND and the takeover address assigned to its primary node (the source system) is ended.
A controlled end is initiated for all data groups that are reading data from the primary node.
When replication successfully ends, the data groups are switched so that they will read from the first backup node listed for recovery nodes for the application group. Then the data groups are started again.
The status of the application group changes to *ACTIVE and the assigned takeover address is started.
The previously assigned primary node is changed to become the last backup node in the application group and the previously assigned first backup node is changed to become the primary node.