Look at your planned or existing use of EDG_EXIT100, EDG_EXIT200, and CBRUXENT installation exits to determine whether customization can be avoided. The function provided by OPENRULE and PRTITION should allow almost any customization related to partitioning, rejecting volumes, ignoring volumes, to be avoided.

Your exit customization does not have to be removed immediately, but can be run alongside the new function, and removed only when you are confident that it is no longer needed. Any existing customization of the CBRUXENT and EDG_EXIT200 installation exits can very likely be removed and replaced with use of PRTITION parmlib commands. Any existing function in the EDG_EXIT100 installation exit that controls the use of a volume, that might fail open or reject a volume, or enable volumes to be ignored without coding EXPDT=98000, can likely be removed and replaced by use of the OPENRULE parmlib commands.

The DFSMSrmm partitioning support based on the PRTITION commands requires either that you use the CBRUXENT exit shipped with DFSMSrmm or that your customized CBRUXENT calls EDGLCSUX and uses the decisions that EDGLCSUX makes.