Naming the CICS regions

Every CICS® region has a network name, defined on a z/OS® Communications Server APPL statement, that uniquely identifies it to z/OS Communications Server.

You specify this name, or applid, on the APPLID system initialization parameter. If a region is a member of a generic resource, its applid and member name are one and the same.

A generic resource—a collection of CICS regions—has a generic resource name. Each CICS region that is to be a member of a generic resource specifies the generic resource name on its GRNAME system initialization parameter. Unlike network names, generic resource names do not have to be defined to z/OS Communications Server. However, they must be distinct from network names, and must be unique within a network.

When you start to use generic resources, you must decide how the generic resource name and the member names are to relate to the applids by which the member regions were known previously:

If you have several TORs, you could continue to use the same applids for the TORs, and choose a new name for the generic resource. Terminal logon procedures will need to be changed to use the generic resource name, and so will connection definitions that are to use the generic resource name.
If you have a single TOR, you could use its applid as the generic resource name, and give it a new applid. Changes to terminal logon procedures (and connection definitions) are minimized, but you need to change z/OS Communications Server definitions, CONNECTION definitions in AORs connected using MRO, and RACF® profiles that specify the old applid.