Specifying takeover commands: DFHCLT TYPE=COMMAND

This macro allows you to specify the commands to be used by the alternate CICS® system during takeover.

COMMAND=command-string

Defines a command that is passed to MVS for execution. CICS does not interpret this command.

The command that is issued in this way most frequently is CEBT PERFORM TAKEOVER.

In multiregion operation (MRO), where there is a simple hierarchy of main and dependent regions, a failing main region can issue this command to each of its dependent regions, if it is necessary that they also move to another CPC.

In a more complex multiregion operation, a failing main region can issue this to its coordinator region, and the coordinator can issue the same command to other main and dependent regions in the same hierarchy of regions. Hence, many MRO-connected regions can move together to another CPC, without operator intervention.

Here are some examples:

A main region without a coordinator sends a command to a dependent region:

DFHCLT TYPE=COMMAND,
        COMMAND='MODIFY CICSDEP,CEBT PERFORM
        TAKEOVER'

A main region sends a command to its coordinator region:

DFHCLT TYPE=COMMAND,
        COMMAND='MODIFY CICSCRD,CEBT PERFORM
        TAKEOVER'

A coordinator region sends commands to main and dependent regions:

DFHCLT TYPE=COMMAND,
        COMMAND='MODIFY CICSMAS,CEBT PERFORM
        TAKEOVER'
DFHCLT TYPE=COMMAND,
        COMMAND='MODIFY CICSDEP,CEBT PERFORM
        TAKEOVER'

You can also issue other commands to any other job running under MVS:

DFHCLT TYPE=COMMAND,
        COMMAND='MODIFY jobname,command
        string'