IMS automation and recovery scenarios

(ZOS) IMS automation and recovery scenarios

This article provides scenarios for IMS™ automation and recovery.

Task IMS automation and recovery scenarios
Startup IMS and any required IMS products, such as IMS Connect, need to be properly installed, initialized, and started before any work flows to an IMS-enabled WebSphere for z/OS application control server region are run.
Shutdown Shutdown the WAS for z/OS application controller that uses IMS as a backing store, then shutdown the IMS service
Handling in-flight or indoubt transactions if there is a failure If there is an error during processing, both IMS and WAS for z/OS rely on the underlying RRS subsystem to handle all rollback notifications to the registered interests. In the case of inflight transactions, RRS will notify all participants that a rollback is required and normal rollback processing will occur in each registered party. In the case of indoubt transactions, it may be necessary to recycle the WAS for z/OS Application Control/Server region to release any pending transaction in the IMS MPRs.
How to determine if IMS is running This is installation-dependent.
What happens to IMS if WAS for z/OS goes down? Should WAS for z/OS happen to go down, one of two situations could occur:

If WAS for z/OS and IMS are currently engaged in a unit of work, then RRS processing would occur and it may be necessary to recycle the application control server regions to release pending transactional work in the IMS MPR.
If WAS for z/OS and IMS are not currently engaged in a unit of work, IMS is not affected.

What happens to other subsystems if IMS goes down? Not applicable
Where to find more information IMS/ESA Operator's Reference

Diagnose problems (using diagnosis tools)
Automation and recovery scenarios and guidelines

Task	IMS automation and recovery scenarios
Startup	IMS and any required IMS products, such as IMS Connect, need to be properly installed, initialized, and started before any work flows to an IMS-enabled WebSphere for z/OS application control server region are run.
Shutdown	Shutdown the WAS for z/OS application controller that uses IMS as a backing store, then shutdown the IMS service
Handling in-flight or indoubt transactions if there is a failure	If there is an error during processing, both IMS and WAS for z/OS rely on the underlying RRS subsystem to handle all rollback notifications to the registered interests. In the case of inflight transactions, RRS will notify all participants that a rollback is required and normal rollback processing will occur in each registered party. In the case of indoubt transactions, it may be necessary to recycle the WAS for z/OS Application Control/Server region to release any pending transaction in the IMS MPRs.
How to determine if IMS is running	This is installation-dependent.
What happens to IMS if WAS for z/OS goes down?	Should WAS for z/OS happen to go down, one of two situations could occur: If WAS for z/OS and IMS are currently engaged in a unit of work, then RRS processing would occur and it may be necessary to recycle the application control server regions to release pending transactional work in the IMS MPR. If WAS for z/OS and IMS are not currently engaged in a unit of work, IMS is not affected.
What happens to other subsystems if IMS goes down?	Not applicable
Where to find more information	IMS/ESA Operator's Reference