Protecting transactions with OTMA

In a z/OS® environment, transaction protection and recovery is managed by z/OS Resource Recovery Services (RRS), part of z/OS Recovery Resource Management Services (RRMS). RRS can apply coordinated changes across multiple mission-critical resources.

OTMA is one of two components that enable IMS to support protected transactions. The second component is APPC/IMS.

To process protected transactions, specify RRS=Y on the control region JCL. IMS then registers as a Resource Manager (RM) with RRMS using the CRGGRM service; it also sets its exits with the Context Services and RRS exit managers using the CRGSEIF service. IMS supports the following RRS exit routines:

PREPARE
COMMIT
BACKOUT
EXIT_FAILED
ONLY_AGENT
SUBORDINATE_FAILED

During initialization, IMS issues message DFS0653I to indicate that it has successfully connected with RRS and that it can now process protected transactions.