and therefore recovery of the most recent units of work cannot be carried out.

 

However, data might be missing from any part of the system log and CICS cannot

 

identify what is missing. CICS cannot examine the log and determine exactly what

 

data is missing, because the log data might appear consistent in itself even when

 

CICS has detected that some data is missing.

These are the messages that CICS issues as it reads the log during a warm or

emergency start and that can help you identify which units of work were

recovered:

DFHRM0402

This message is issued for each unit of work when it is first encountered

on the log.

DFHRM0403 and DFHRM0404

One of these messages is issued for each unit of work when its context is

found. The message reports the state of the unit of work.

DFHRM0405

This message is issued when a complete keypoint has been recovered from

the log.

If you see that message DFHRM0402 is issued for a unit of work, and it is matched

by message DFHRM0403 or DFHRM0404, you can be sure of the state of the unit

of work. If you see message DFHRM0405, you can use the preceding messages to

determine which units of work are incomplete, and you can also be sure that none

of the units of work is completely missing.

 

Another class of problem with the system log is one that does not indicate any loss

 

of previously logged data; for example, access to the logstream was lost due to

 

termination of the MVS system logger address space. This class of problem causes

 

an immediate termination of CICS because a subsequent emergency restart will

 

probably succeed when the cause of the problem has been resolved.

 

For information about how to deal with system log problems, see the CICS Problem

 

Determination Guide.

How the state of the CICS region is reconstructed

CICS recovery manager uses the type-of-restart indicator in its domain state record from the global catalog to determine which type of restart it is to perform.

This indicator operates as follows:

vBefore the end of initialization, on all types of startup, CICS sets the indicator in the control record to “emergency restart needed”.

vIf CICS terminates normally, this indicator is changed to “warm start possible”.

vIf CICS terminates abnormally because the system log has been corrupted and is no longer usable, this indicator is changed to “no restart”. After fixing the system log, perform an initial start of the failed CICS region.

vFor an automatic start (START=AUTO):

If the indicator says “warm start possible”, CICS performs a warm start.

If the indicator says “emergency restart needed”, CICS performs an emergency restart.

34CICS TS for z/OS 4.1: Recovery and Restart Guide

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IBM SC34-7012-01 manual How the state of the Cics region is reconstructed, DFHRM0403 and DFHRM0404