Files – IBM SC34-7012-01 User Manual

Page 58

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– CICS requests the SMSVSAM server, if connected, to release all RLS retained

locks.

– CICS does not rebuild the non-RLS retained locks.

v

CICS requests the SMSVSAM server to clear the RLS sharing control status for
the region.

v

CICS does not restore the dump table, which may contain entries controlling
system and transaction dumps.

v

CICS preserves resynchronization information about distributed units of
work—information regarding unit of work obligations to remote systems, or to
non-CICS resource managers (such as DB2) connected through the RMI. For
example, the preserved information includes data about the outcome of
distributed UOWs that is needed to allow remote systems (or RMI resource
managers) to resynchronize their resources.

Note:

The system log information preserved does not include before-images of

any file control data updated by a distributed unit of work. Any changes made
to local file resources are not backed out, and by freeing all locks they are
effectively committed. To preserve data integrity, perform a warm or emergency
restart using START=AUTO.

v

CICS retrieves its logname token from the recovery manager control record for
use in the “exchange lognames” process during reconnection to partner systems.
Thus, by using the logname token from the previous execution, CICS ensures a
warm start of those connections for which there is outstanding resynchronization
work.

To perform these actions on a cold start, CICS needs the contents of the catalog
data sets and the system log from a previous run.

See the CICS System Definition Guide for details of the actions that CICS takes for
START=COLD in conjunction with various states of the global catalog and the
system log.

The DFHRMUTL utility returns information about the type of previous CICS
shutdown which is of use in determining whether a cold restart is possible or not.
For further details, see the CICS Operations and Utilities Guide.

Files

All previous file control state data, including file resource definitions, is lost.

If RLS support is specified, CICS connects to the SMSVSAM, and when connected
requests the server to:

v

Release all RLS retained locks

v

Clear any “lost locks” status

v

Clear any data sets in “non-RLS update permitted” status

For non-RLS files, the CICS enqueue domain does not rebuild the retained locks
relating to shunted units of work.

File resource definitions are installed as follows:

VSAM

Except for the CSD itself, all VSAM file definitions are installed from the
CSD. You specify these in groups named in the CSD group list, which you

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CICS TS for z/OS 4.1: Recovery and Restart Guide

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