Due to connectivity constraints on old DASD and tape, it might be necessary to know the system and Parallel Sysplex® where an ACS routine is being executed in order to direct the allocation to a storage groups that is accessible from the current system. To support this function, SMS ACS processing uses the &SYSNAME and &SYSPLEX read-only variables.

Do not use the &SYSPLEX variable in ACS routines for JES3 systems as Parallel Sysplex name support is not supported in a JES3 environment. Also, ACS routines for JES3 systems should not rely on the &SYSNAME variable, as the system on which the ACS routines are run (during converter/interpreter) might have nothing to do with the system on which the job is eventually executed.