If an installation has been running with its tape libraries in unpartitioned mode for some period of time, the tape volumes will already be assigned to default categories. When the partitioning-related DEVSUPxx parameters are used, special processing is necessary to move volumes to the new categories established through DEVSUPxx:

• Modify the DEVSUPxx PARMLIB member associated with each system or sysplex, or both, in each TCDBplex.
• If the library is a Virtual Tape Server (VTS) or a Peer-to-Peer VTS and you wish to take advantage of the library's nonspecific (scratch) mount performance, define the Fast Ready attribute at the library manager for the DEVSUPxx scratch categories to be used at the library.
• IPL all systems in the TCDBplex to activate the DEVSUPxx changes.
• Ensure that no jobs which require scratch mounts in a library are run. This may be done by varying all library-resident tape drives offline to all systems.
• Start the OAM address space and make sure that all tape libraries are online. The tape drives must remain offline.
• Obtain a list of volumes whose storage group name is ‘*SCRTCH*’ using the ISMF Mountable Tape Volume Application. It is a good idea to do this one library at a time by also specifying the library name.
• Use the ISMF ALTER command (not the line operator) to change the volume use attribute for all volumes in the list from scratch to scratch. This causes the library manager category for each volume to be changed from the default value to the new value established through DEVSUPxx. All volumes in the default scratch categories and in the error category are changed to the new DEVSUPxx scratch categories.
• It is not necessary to change the category of private volumes. When a private volume is returned to scratch, its category will be changed to one of the new scratch categories.
• Vary the tape drives online as appropriate, and start to run normal tape job streams.