Automatically unmounting the version file system

The version file system can be unmounted automatically if the version auto-unmount attribute of the version file system is set prior to changing to a new version file system.

Note: A delay of 30 minutes will occur before the first attempt to unmount the unused version root.
To verify the value of the version auto-unmount attribute, issue one of the following commands:
  • DISPLAY OMVS,FILES
  • D OMVS,OPTIONS
  • F BPXOINIT,FILESYS=DISPLAY

To set the version auto-unmount attribute for the current version file system, use parmlib statement VERSION=('nnnn',UNMOUNT) when IPLing with a new version file system, or use the statement with SET OMVS or SETOMVS VERSION=('nnnn',UNMOUNT).

When the file system with version auto-unmount attribute specified is no longer used as a version file system by any system in the sysplex, it will be unmounted automatically along with the file systems that are mounted under it. This unmount action will also be done during dead system takeover (member gone recovery) for a file system with the version auto-unmount attribute.

Restriction: All systems in the sysplex must be at least z/OS V2.3 or version auto-unmount processing will not be performed. To automatically unmount version file systems, perform these one-time actions once all systems in the sysplex are at z/OS V2.3 or later:
  1. Change your BPXPRMxx file system member to specify VERSION('nnnn',UNMOUNT).
  2. Use SET OMVS or SETOMVS to change any current version file system to UNMOUNT.