How to perform a subsystem restart with the z/OS Automatic Restart Manager

You can use the z/OS® Automatic Restart Manager (ARM) to restart a subsystem or a job after a failure of the subsystem or environment in which it is running. IMS supports the z/OS Automatic Restart Manager in the DB/DC, DBCTL, DCCTL, and XRF environments.

The following subsystems also use the z/OS Automatic Restart Manager:

• The IRLM subsystem
• The CQS subsystem
• The CSL Open Database Manager (ODBM)
• The CSL Operations Manager (OM)
• The CSL Resource Manager (RM)
• The CSL Structured Call Interface (SCI)

IMS batch environments and IMS utilities do not support the z/OS Automatic Restart Manager.

After a failure, the z/OS Automatic Restart Manager will restart only the IMS control region and the CQS subsystem (each independently of the other). Other regions (such as DLISAS and DBRC) are in turn restarted by the IMS control region, and IMS dependent regions are typically restarted using automation.

In an XRF environment, the active IMS subsystem is automatically de-registered from the z/OS Automatic Restart Manager while the alternate IMS subsystem is in its tracking phase. Thus, the active subsystem is not be restarted after a failure; instead, the XRF alternate takes over as expected.

The z/OS Automatic Restart Manager ignores AUTO=N in the IMS startup parameters.

If an IMS or CQS subsystem abends before it completes restart, it is de-registered from the z/OS Automatic Restart Manager so that the abend can be fixed before attempting restart again.

If an IMS or CQS subsystem that is registered with the z/OS Automatic Restart Manager is canceled by the z/OS operator (using the CANCEL command), that IMS subsystem is not restarted by the z/OS Automatic Restart Manager unless the operator includes the ARMRESTART keyword on the command.