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You can do this by specifying START=INITIAL as a system initialization parameter,
or by running the recovery manager's utility program (DFHRMUTL) to override
the type of start indicator to force an initial start.
See the CICS Operations and Utilities Guide for information about the DFHRMUTL
utility program.
Dynamic RLS restart
If a CICS region is connected to an SMSVSAM server when the server fails, CICS
continues running, and recovers using a process known as dynamic RLS restart.
An SMSVSAM server failure does not cause CICS to fail, and does not affect any
resource other than data sets opened in RLS mode.
When an SMSVSAM server fails, any locks for which it was responsible are
converted to retained locks by another SMSVSAM server within the sysplex, thus
preventing access to the records until the situation has been recovered. CICS
detects that the SMSVSAM server has failed the next time it tries to perform an
RLS access after the failure, and issues message DFHFC0153. The CICS regions that
were using the failed SMSVSAM server defer in-flight transactions by abending
units of work that attempt to access RLS, and shunt them when the backouts fail
with “RLS is disabled” responses. If a unit of work is attempting to commit its
changes and release RLS locks, commit failure processing is invoked when CICS
first detects that the SMSVSAM server is not available (see “Commit-failed
recovery” on page 83).
RLS mode open requests and RLS mode record access requests issued by new
units of work receive error responses from VSAM when the server has failed. The
SMSVSAM server normally restarts itself without any manual intervention. After
the SMSVSAM server has restarted, it uses the MVS event notification facility
(ENF) to notify all the CICS regions within its MVS image that the SMSVSAM
server is available again.
CICS performs a dynamic equivalent of emergency restart for the RLS component,
and drives backout of the deferred work.
Recovery after the failure of an SMSVSAM server is usually performed
automatically by CICS. CICS retries any backout-failed and commit-failed units of
work. In addition to retrying those failed as a result of the SMSVSAM server
failure, this also provides an opportunity to retry any backout failures for which
the cause has now been resolved. Manual intervention is required only if there are
units of work which, due to the timing of their failure, were not retried when CICS
received the ENF signal. This situation is extremely unlikely, and such units of
work can be detected using the INQUIRE UOWDSNFAIL command.
Note that an SMSVSAM server failure causes commit-failed or backout-failed units
of work only in the CICS regions registered with the server in the same MVS
image. Transactions running in CICS regions in other MVS images within the
sysplex are affected only to the extent that they receive LOCKED responses if they
try to access records protected by retained locks owned by any CICS regions that
were using the failed SMSVSAM server.
Chapter 3. Shutdown and restart recovery 37