PI40139: MQGET OF NON-PERSISTENT MESSAGE INCORRECTLY BACKED OUT DURING PEER LEVEL RECOVERY FOLLOWING LOSS OF CONNECTIVITY

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• MQGET of non-persistent message incorrectly backed out during
  peer level recovery following loss of connectivity
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of WebSphere MQ for z/OS Version 7 *
  *                 Release 1 Modification 0.                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: If connection is lost to the CF during  *
  *                      a get of a non-persistent message from  *
  *                      a shared queue with                     *
  *                      MQGMO_SYNCPOINT_IF_PERSISTENT then the  *
  *                      got message may unexpectedly still be   *
  *                      on the queue.                           *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When a MQGET is performed for a non-persistent message from a
  shared queue, the get processing calls CSQESYNC to commit the
  in-progress get. However if connection is lost to the coupling
  facility during this processing, the message may be returned and
  also backed out from the uncommitted queue, returning the
  message to the queue, resulting in the message being possibly
  duplicated.
  

Problem conclusion

• CSQESYNC processing has been updated to correct this scenario,
  to not return the message in this case, when connectivity is
  lost to the CF. This ensures the message will be correctly
  backed off the uncommitted queue when connectivity is restored
  to the CF. This ensures the message is not duplicated, and is
  not returned more than once.
  100Y
  CSQESYNC
  CSQIMGES
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UI37324

Modules/Macros

• CSQESYNC CSQIMGES
  

Fix information

• Fixed component name

  WMQ Z/OS V7

• Fixed component ID

  5655R3600

Applicable component levels

• R100 PSY UI37324

     UP16/05/26 P F605 Ž

Fix is available

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