Red Alert - Potential for loss of access to data on a volume due to erroneous 'End of File' written to the VTOC or VTOCIX on z/OS V2R2 DFSMS

Here's the information for the second Red Alert. It was first published on November 2 (link) with an update on November 4 (link). I'm giving you the info from the updated version

Abstract:

Potential for loss of access to data on a volume due to erroneous 'End of File' written to the VTOC on z/OS V2R2 DFSMS (HDZ2220)

Users Affected:

Systems running z/OS V2R2 with DFSMS Secondary Space Reduction (SSR) function enabled (default)

Description:

For systems with DFSMS Device Manager Secondary Space Reduction enabled, the VTOC may be updated incorrectly if an AbendE37 occurs when no storage space is available while trying to extend to secondary extents on a new volume.

Recommended Actions:

Disable z/OS SSR function of Device Manager until fix for APAR OA51499 is available (instructions below).
Please note: If recent PTF UA82730 is applied then you must remove this PE PTF or apply ++APAR for OA51474 prior to disabling SSR. Please see APAR OA51499 Local Fix for additional details.
Disabling z/OS SSR:

• Issue z/OS Command F DEVMAN,DISABLE(SSR) for current IPL

                          -or-  

• Update DEVSUPxx parmlib member to include DISABLE(SSR) and issue z/OS command SET DEVSUP=(xx,yy) or SET DEVSUP=xx to all systems to persist across IPL's.

If you haven't signed up to the Red Alerts by now, you really should do it. Just go over here.