IBM SC34-7012-01 Server User Manual


 
Start requests
In general, start requests are recovered only when they are associated with
recoverable data or are protected and the issuing unit of work is indoubt.
However, recovery can be further limited by the use of the specific COLD option
on the system initialization parameter for TS, ICP, or BMS. If you suppress start
requests by means of the COLD option on the appropriate system initialization
parameter, any data associated with the suppressed starts is discarded. The rules
are:
v ICP=COLD suppresses all starts including BMS starts.
v TS=COLD (or TS main only) suppresses all starts that had data associated with
them.
v BMS=COLD suppresses all starts relating to BMS paging.
Start requests that have not been suppressed for any of the above reasons either
continue to wait if their start time or interval has not yet expired, or are processed
immediately.
For start requests with terminals, consider the effects of the CICS restart on the set
of installed terminal definitions. For example, if the terminal specified on a start
request is no longer installed after the CICS restart, CICS invokes an XALTENF
global user exit program (if enabled), but not the XICTENF exit.
Terminal control resources
Terminal control information is installed from the warm keypoint in the global
catalog, or installed from the TCT, depending on whether the definitions are
CSD-defined or TCT-defined.
CSD-defined resource definitions
CICS retrieves the state of the CSD-eligible terminal control resources from the
catalog entries that were written:
v During a previous cold start
v When resources were added with EXEC CICS CREATE or CEDA INSTALL
v When resources were added with autoinstall (subject to the AIRDELAY system
initialization parameter)
v Rewritten to the catalog at an intervening warm shutdown
The state of the catalog may have been modified for some of the above resources
by their removal with a CEMT, or an EXEC CICS DISCARD, command.
CICS uses records from the system log, written when any terminal resources were
being updated, to perform any necessary recovery on the cataloged data. This may
be needed if terminal resources are installed or deleted while CICS is running, and
CICS fails before the operation is completed.
Some terminal control resources are installed or deleted in “installable sets” as
described under “Committing and cataloging resources installed from the CSD” on
page 49. If modifications are made to terminal resource definitions while CICS is
running, CICS writes the changes in the form of forward recovery records to the
system log. If the installation or deletion of installable sets or individual resources
64 CICS TS for z/OS 4.1: Recovery and Restart Guide