Using multiple IMS systems at different release levels

If your environment includes multiple IMS systems at different release levels, several considerations related to system definition apply.

If you are running multiple copies of IMS at different release levels under the same operating system, the operating system must be at a version and release level that is required for the most recent release of IMS.

If you are installing different release levels of IMS in the same z/OS® system, remember that running a system using the SVC from a lower-level system is not supported. For example, running an IMS Version 12 system using the SVC from IMS Version 11 is not supported. Similarly, running an IMS Version 12 system using the SVC from IMS Version 10 is not supported.

As of IMS Version 11, IMS uses a dynamic abend dump formatting module (DFSAFMX0). If you are running only versions of IMS that are Version 11 or later, you do not need to install the static abend dump formatting module (DFSAFMD0) on the host z/OS system. If you want to have IMS online dump formatting, and your z/OS system is running any jobs (either online or batch) for IMS Version 10 or earlier, the DFSAFMD0 module must be installed on the z/OS system.

For example, if you are running IMS Version 12 and Version 11, you must install the version of DFSAFMD0 that shipped with either IMS Version 12 or Version 11. For information about installing DFSAFMD0, see IMS Version 15.2 System Administration.