MVS system recovery and sysplex recovery
When an MVS™ image fails, all CICS® regions and the SMSVSAM server in that image also fail. All RLS locks belonging to CICS regions in the image are retained by SMSVSAM servers in the other MVS systems.
When the MVS image restarts, recovery for all resources is through CICS emergency restart. If any CICS region completes emergency restart before the SMSVSAM server becomes available, it performs dynamic RLS restart as soon as the server is available.
The surviving MVS images should be affected by the failure only to the extent that more work is routed to them. Also, tasks that attempt to access records that are locked by CICS regions in the failed MVS image receive the LOCKED response.
If all the MVS images in a sysplex fail, the first SMSVSAM server to restart reconnects to the lock structure in the coupling facility and converts all the locks into retained locks for the whole sysplex.
Recovery from the failure of a sysplex is just the equivalent of multiple MVS failure recoveries.