IBM SC34-7012-01 manual Shutdown requested by the operating system, Dfhcesd

2.If the default shutdown assist transaction CESD is run, it allows as many tasks as possible to commit or back out cleanly, but within a shorter time than that allowed on a normal shutdown. See “The shutdown assist transaction” on page 30 for more information about CESD, which runs the CICS-supplied program

DFHCESD.

3.None of the programs listed in the shutdown PLT is executed.

4.CICS does not write a warm keypoint or a warm-start-possible indicator to the global catalog.

5.CICS does not close files managed by file control. It is left to VSAM to close the files when VSAM is notified by MVS that the address space is terminating. This form of closing files means that a VSAM VERIFY is needed on the next open of the files closed in this way, but this is done automatically.

6.VTAM sessions wait for the restarted region to initialize or until the expiry of the interval specified in the PSDINT system initialization parameter, whichever is earlier.

The next initialization of CICS must be an emergency restart, in order to preserve data integrity. An emergency restart is ensured if the next initialization of CICS specifies START=AUTO. This is because the recovery manager’s type-of-restart indicator is set to “emergency-restart-needed” during initialization and is not reset in the event of an immediate or uncontrolled shutdown. See “How the state of the CICS region is reconstructed” on page 34.

Note: A PERFORM SHUTDOWN IMMEDIATE command can be issued, by the operator or by the shutdown assist transaction, while a normal or immediate shutdown is already in progress. If this happens, the shutdown assist transaction is not restarted; the effect is to force an immediate shutdown with no shutdown assist transaction.

If the original PERFORM SHUTDOWN request specified a normal shutdown, and the restart manager (ARM) was active, CICS is restarted (because CICS will not de-register from the automatic restart manager until the second quiesce stage of shutdown has completed).

Shutdown requested by the operating system

This type of shutdown can be initiated by the operating system as a result of a program check or an operating system abend.

A program check or system abend can cause either an individual transaction to abend or CICS to terminate. (For further details, see “Processing operating system abends and program checks” on page 94.)

A CICS termination caused by an operating system request:

vDoes not guarantee that user tasks will complete.

vDoes not allow shutdown PLT programs to execute.

vDoes not write a warm keypoint or a warm-start-possible indicator to the global catalog.

vTakes a system dump (unless system dumps are suppressed by the DUMP=NO system initialization parameter).

vDoes not close any open files. It is left to VSAM to close the files when VSAM is notified by MVS that the address space is terminating. This form of closing files means that a VSAM VERIFY is needed on the next open of the files closed in this way, but this is done automatically.

Chapter 3. Shutdown and restart recovery 29