Database utility coexistence considerations

Coexistence restrictions apply to the use of some database utilities.

JCL from earlier versions of IMS might need to be changed because IMS 15 DBRC uses time-stamp precision to the microsecond.

Recommendation: Use DBRC with all IMS 15 database change accumulation and database recovery jobs, especially during migration and coexistence.

Attention: Other utility programs (such as Log Merge and Log Analysis) work properly only when they process data that was created by an IMS subsystem or batch application program that is at the same version level as the utility program. Otherwise, the results are unpredictable and the output is unreliable.

Restrictions:

IMS 15 utilities must be used whenever the input data for a DBDS contains log, image copy, or change accumulation records created by the IMS 15 system.
Log records generated by a particular version of IMS must use that same version (or later) of the Database Recovery (DFSURDB0) and Database Change Accumulation (DFSUCUM0) utilities to process those logs. For example, the IMS 14 utilities can process either IMS Version 13 or IMS 14 log records, but cannot process IMS 15 log records.