CSD compatibility between different CICS releases

Most releases of CICS change the CICS-supplied groups of resource definitions that are included in the DFHLIST group list. The old versions of the CICS resource definitions are retained in compatibility groups. If you share the CSD between different CICS releases, these compatibility groups are needed to support earlier releases.

After you upgrade a CSD, if you plan to share the CSD with earlier releases of CICS, include the appropriate DFHCOMPx compatibility groups in your startup group list. Table 1 shows you which DFHCOMPx groups to include for each earlier release.

Do not attempt to share a CSD with a CICS region that is running at a higher release level than the CSD.

You must install the compatibility groups in the correct order, as shown in the table. For example, to run a CICS TS 5.2 region with a CSD that is upgraded to CICS TS 5.5, add the DFHCOMPI compatibility group, followed by the DFHCOMPH compatibility group, to the end of your group list.