You can perform some inventory management activities only under specific conditions:

• In an environment where the DFSMSrmm control data set is shared, and you use system-managed tape, you must run inventory management on a system that has access to the TCDB. If the TCDB is not shared by each system that is sharing the control data set, and there are multiple TCDBs, run inventory management at least once against each TCDB on a system that has access to that TCDB.
• When either of these conditions exist, you must run inventory management on a system that has access to the catalogs.
  • The DFSMSrmm control data set is shared, the DFSMSrmm control data set and catalogs are not synchronized, and you want to retain data sets that are based on the catalog information.
  • The DFSMSrmm parmlib OPTION command UNCATALOG is coded with Y or S to indicate that catalog processing is required.
• In an unshared user catalog environment, you must specify the DFSMSrmm EDGRMMxx parmlib OPTION command CATSYSID operand to use DFSMSrmm. When you use unshared catalogs, ensure that the DFSMSrmm control data set and the user catalogs are synchronized. You must run inventory management expiration processing on each different catalog environment.
• When DFSMSrmm is active, you cannot reorganize the control data set.
• The DFSMSrmm subsystem address space performs all inventory management functions, except backing up the control data set and backing up the journal. During inventory management processing, the address space running EDGHSKP waits until processing completes. Once the subsystem processing completes, EDGHSKP performs backup processing in its home address space; this can include the backup of the DFSMSrmm control data set and the journal.
• When inventory management functions are active, you can continue using RMM TSO subcommands and DFSMSrmm continues to record tape usage.
• You must define at least one vital record specification in order to run DFSMSrmm vital record processing. The EDGRMMxx parmlib OPTION command VRSMIN operand provides control over this processing.
  Example: Use the RMM ADDVRS subcommand to define a vital record specification.

  RMM ADDVRS DSN('**') WHILECATALOG