Using the z/OS Automatic Restart Manager (ARM)

Use this topic to understand how you can use ARM to automatically restart your queue managers.

This section contains information about the following topics:

What is the ARM?

The z/OS® Automatic Restart Manager (ARM) is a z/OS recovery function that can improve the availability of your queue managers. When a job or task fails, or the system on which it is running fails, ARM can restart the job or task without operator intervention.

If a queue manager or a channel initiator has failed, ARM restarts it on the same z/OS image. If z/OS, and hence a whole group of related subsystems and applications have failed, ARM can restart all the failed systems automatically, in a predefined order, on another z/OS image within the sysplex. This is called a cross-system restart.

Restart the channel initiator by ARM only in exceptional circumstances. If the queue manager is restarted by ARM, restart the channel initiator from the CSQINP2 initialization data set (see Using ARM in an IBM MQ network ).

You can use ARM to restart a queue manager on a different z/OS image within the sysplex in the event of z/OS failure. The network implications of IBM® MQ ARM restart on a different z/OS image are described in Using ARM in an IBM MQ network.

To enable automatic restart:

Set up an ARM couple data set.
Define the automatic restart actions that you want z/OS to perform in an ARM policy.
Start the ARM policy.

Also, IBM MQ must register with ARM at startup (this happens automatically).

Note: If you want to restart queue managers in different z/OS images automatically, you must define every queue manager as a subsystem in each z/OS image on which that queue manager might be restarted, with a sysplex wide unique four character subsystem name.

ARM couple data sets

Ensure that you define the couple data sets required for ARM, and that they are online and active before you start any queue manager for which you want ARM support. IBM MQ automatic ARM registration fails if the couple data sets are not available at queue manager startup. In this situation, IBM MQ assumes that the absence of the couple data set means that you do not want ARM support, and initialization continues.

See z/OS MVS Setting up a Sysplex for information about ARM couple data sets.