To use ACS routines or exit selected scratch pooling, you must define messages IEC501A, IEF233A, IAT5110, and IAT5210 using the DFSMSrmm MNTMSG commands in parmlib as described in Defining mount and fetch messages: MNTMSG. These messages provide the pool identifiers to the operator, the job name, and data set name information to the EDG_EXIT100 exit.

DFSMSrmm can update mount messages and tape drive displays with the pool prefix, storage group name, or pool name. DFSMSrmm can also provide information to some tape automation software installed on your system through the tape mount messages. DFSMSrmm updates messages IEF233A and IEC501A, and IAT5210 for JES3 to include the pool identifier that you select. You can define Basic Tape Library Support (BTLS) category names so that DFSMSrmm can be used to manage volumes in a BTLS-managed tape library. If you use BTLS scratch category names as DFSMSrmm pool names, DFSMSrmm can be used to direct which volumes BTLS will use for each scratch mount.

For JES3, to find out which pool was used to satisfy a request, install the USERMOD EDG3UX71; users can see mount messages with the pool identifier in the output from their batch jobs. Users allowed to view the SYSLOG can see the updated messages in the SYSLOG.