For reliable diagnosis, it is important that you have dumps of
the MVS logger address space and (if applicable) the coupling facility structures
used by the system log.
Before you begin
This means that, before performing the diagnostic run, you will probably
need to set a SLIP trap, as described in Setting a SLIP trap.
About this task
You need to set a SLIP if any of the following are true:
- You have not applied MVS APAR OW27057.
- MVS did not produce a dump of the logger address space.
- MVS produced a dump of the logger address space but you have not kept
the dump.
- The CICS system log uses coupling facility log streams.
When specifying the SLIP, note the following:
Procedure
- Set the trap for the specific DFHLG07xx message
that CICS issued when the original failure occurred.
When
the diagnostic run occurs and the failure repeats, the message will drive
the SLIP.
Occasionally, the DFHLG07xx message that
was issued at the time of the original failure is not repeated during a diagnostic
run. Instead, a different DFHLG07xx message is issued.
Therefore the SLIP is not triggered. If this happens, perform another diagnostic
run. This time, however, set the SLIP for the DFHLG07xx message
that was issued during the first diagnostic run.
- Change the JOBLIST parameter in the example
SLIP to read
You do not need to specify a dump of the CICS system, because one is
taken automatically by the diagnostic run mechanism.
- Specify a dump of the MVS logger address space.
See
the example SLIP. If you have applied MVS APAR OW27057, and the original failure
occurred because the MVS logger was unable to find a specific log stream block
identifier, an extra dump may be produced.
- If the system log uses coupling facility log streams, specify a
dump of the coupling facility structure.
You can get the name
of the structure from the two DFHLG0104 messages that were issued when CICS
connected to DFHLOG and DFHSHUNT during the run in which the failure occurred.
If DFHLOG and DFHSHUNT use separate coupling facility structures, dump
both structures. Specify the names of both structures on the STRLIST
parameter.