The SYSMOD being installed must specify the RMID of the associated target system element on the PRE or SUP operand. If the RMID of the target system element is the same as its FMID, the element has not been replaced by any SYSMOD, and so the SYSMOD being installed need not specify the RMID value in the PRE or SUP operand.

If the element being installed is a ++SRC/++SRCUPD or a ++MAC/++MACUPD resulting in an assembly that replaces a target system module (element), the SYSMOD being installed must specify as one of its PRE or SUP operand values the RMID of the corresponding target system module that is replaced by the assembly. If the target system module is itself the result of an assembly (RMIDASM indicator set in the MOD entry), an exception to this requirement is made, because the reassembly picks up any changes caused by the SYSMOD that last replaced the module through an assembly.

If the SYSMOD being processed does not specify the RMID of the element on the PRE or SUP operand, SMP/E does not apply that SYSMOD, because doing so would regress the service supplied by the SYSMOD represented by the RMID. If you want to allow the RMID SYSMOD to be regressed, you can specify the BYPASS(ID) operand of the APPLY command.

SMP/E makes an exception to this processing requirement if the SYSMOD being processed is itself the RMID of the element and REDO was specified on the APPLY command. In this case, the SYSMOD being processed is the highest level of the element and it is being installed again, therefore SMP/E allows the SYSMOD to be installed and to replace the current element.