You may need to use more than one version of the CICS® Type 3 SVC, for example to test service applied to the DFHCSVC module while using the current version in a production system.
You can run several CICS regions, at different release levels, in the same MVS™ image, with each region using its own version of the CICS SVC. However, if some of those regions use MRO, all regions that use MRO must use the latest CICS Type 3 SVC (DFHCSVC module) and the latest DFHIRP module. For information about using the latest SVC with earlier releases of CICS, see MRO between different CICS releases with a changed SVC number and a pre-Version 3 Installation Guide.
To use more than one version of the CICS SVC, rename the new SVC module in the LPA, then respecify the SVC in the SVCPARM statements, as outlined in Defining the CICS SVCs to your MVS. To rename the new CICS SVC module, use the renaming facility of ISPF or IEBCOPY, or the TSO command RENAME, renaming the module to a unique name of your choice. We recommend that you use SMP/E to rename the CICS SVC module in the SDFHLPA library. Use the SMP/E RENAME command to inform SMP/E of the change to the name of the CICS SVC module. Therefore, if you later use SMP/E to apply service to that module, the service is applied to the renamed module in the LPA, not the DFHCSVC module.
For example, you might want to use an SVC number 255 for a test CICS region, as well as the default CICS SVC number 216 for your production system:
++USERMOD(umod1) .
++VER(C150) FMID(HCI6400) .
++RENAME (DFHCSVC) TONAME(newname) .
SVCPARM 216,REPLACE,TYPE(3),EPNAME(DFHCSVC)
SVCPARM 215,REPLACE,TYPE(6),EPNAME(DFHHPSVC) [Only required for HPO]
SVCPARM 255,REPLACE,TYPE(3),EPNAME(newname) [New CICS SVC version]
All the SVCPARM statements apply to the same IEASVCxx member of the SYS1.PARMLIB library.