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Chapter 7. Automatic restart management
CICS uses the automatic restart manager (ARM) component of MVS to increase the
availability of your systems.
MVS automatic restart management is a sysplex-wide integrated automatic restart
mechanism that performs the following tasks:
v Restarts an MVS subsystem in place if it abends (or if a monitor program
notifies ARM of a stall condition)
v Restarts all the elements of a workload (for example, CICS TORs, AORs, FORs,
DB2, and so on) on another MVS image after an MVS failure
v Restarts CICS data sharing servers in the event of a server failure.
v Restarts a failed MVS image
CICS reconnects to DBCTL and VTAM automatically if either of these subsystems
restart after a failure. CICS is not dependent on using ARM to reconnect in the
event of failure.
The MVS automatic restart manager provides the following benefits:
v Enables CICS to preserve data integrity automatically in the event of any system
failure.
v Eliminates the need for operator-initiated restarts, or restarts by other automatic
packages, thereby:
– Improving emergency restart times
– Reducing errors
– Reducing complexity.
v Provides cross-system restart capability. It ensures that the workload is restarted
on MVS images with spare capacity, by working with the MVS workload
manager.
v Allows all elements within a restart group to be restarted in parallel. Restart
levels (using the ARM WAITPRED protocol) ensure the correct starting sequence
of dependent or related subsystems.
Restrictions
You cannot use MVS automatic restart for CICS regions running with XRF. If you
specify XRF=YES, CICS deregisters from ARM and continues initialization with
XRF support.
MVS automatic restart management is available only to those MVS subsystems that
register with ARM. CICS regions register with ARM automatically as part of CICS
system initialization. If a CICS region fails before it has registered for the first time
with ARM, it will not be restarted. After a CICS region has registered, it is
restarted by ARM according to a predefined policy for the workload.
CICS ARM processing
A prime objective of CICS support for the MVS automatic restart manager (ARM)
is to preserve data integrity automatically in the event of any system failure.
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