Planned shutdowns using F OMVS,SHUTDOWN

Steps for shutting down z/OS UNIX using F OMVS,SHUTDOWN describes how to use the F OMVS,SHUTDOWN operator command for a planned shutdown and reIPL. Consider using it if you plan to recustomize and reinitialize the z/OS UNIX environment without reIPLing. Using F OMVS,SHUTDOWN along with F OMVS,RESTART might allow you to avoid a system outage by providing the ability to shut down and then reinitialize the z/OS UNIX environment without the need for a reIPL.

F OMVS,SHUTDOWN is an alternative to F BPXOINIT,SHUTDOWN=... commands for synchronizing data to the file systems and unmounting or moving file system ownership before a planned shutdown.

Guideline: Sometimes F OMVS,SHUTDOWN cannot shut down z/OS UNIX completely and you must do a reIPL in order to correct the condition that is requiring the shutdown. With F OMVS,SHUTDOWN and F OMVS,RESTART, some reconfiguration tasks can be accomplished that otherwise would have required a reIPL. These tasks include the following steps:

Reconfiguring a system to go from a non-shared file system to a shared file system.
Completely applying a new file system file structure.

However, there are some tasks that you cannot accomplish using these commands, as follows:

Installing maintenance to the z/OS UNIX component.
Resolving severe system outages.

Follow the recommended pre-shutdown procedure described in Steps for shutting down z/OS UNIX using F OMVS,SHUTDOWN when using F,OMVS,SHUTDOWN. If you do not, the risk of having to do a reIPL is far greater.

If you want to shut down the system as part of JES2 maintenance and do not want to reIPL the system, issue F BPXOINIT,SHUTDOWN=FORKS as described in Partial shutdowns for JES2 maintenance.