Compatibility mode (CSD file sharing)

CICS® allows a CSD file and its resource definitions to be shared between different CICS systems. The systems might be running the same or different releases of CICS. Compatibility mode is intended for use when you want to create or change resource definitions on a CSD file that is shared between different releases.

All maintenance should be done under the latest release of CICS. This avoids the risk of earlier releases modifying entries created under more recent releases with new attributes that the older version does not recognize. Ensure this by restricting write access to the CSD file to the latest release. See the CICS System Definition Guide for further details on defining CSD files.

Compatibility mode is entered by using PF2 on the CEDA panels where it is available. It gives you access to those attributes that were current at your earlier release, but are obsolete at your later release. However, you can use compatibility mode only with commands affecting individual resources: you cannot perform generic commands (ALTER, DEFINE, and VIEW) in compatibility mode.

There is more information about issues relating to compatibility mode in the following places: