PI25702: WEBSPHERE MQ, UNCOMMITTED MQGET IS NOT BEING BACKED-OUT FOLLOWING THE RESTART OF RRS

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• The MQGET is for a non-persistent message and was issued by WAS
  system ANS112S, EB 248BCB70, the EB being associated with MQ
  private context CDBBDF3D 802C0C34 02000000 04B340A8 and a
  global RRS transaction (so CCBRRSGL is set). When RRS was
  restarted, the queue-manager's resync processing in CSQ3RRSR
  detected that this context needed to be ended (and hence the
  transaction backed-out) and therefore scheduled deferred
  end-context processing. However, when the deferred end-context
  was processed by CSQMCTXE it detected that there was a global
  RRS tranaction and did not perform end-context processing, the
  assumption being that RRS will subsequently drive the
  queue-manager for commit or abort, after which the context
  could be ended. However, as RRS was restarted when the
  transaction was inflight this was never going to happen, hence
  the MQGET remained uncommitted.
  
  
  Additional Symptom(s) Search Keyword(s): RRS UNCOM
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of WebSphere MQ for z/OS Version 7 *
  *                 Release 0 Modification 1 and Release 1       *
  *                 Modification 0.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: Uncommitted messages that are part of   *
  *                      an RRS-coordinated global transaction   *
  *                      may not be correctly backed out after a *
  *                      restart of RRS                          *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When RRS is stopped and restarted it resynchronizes with MQ in
  order to correctly resolve any in-doubt transactions.
  
  When an MQ transaction is not yet in an in-doubt state (because
  it is still in-flight and has not been committed) then we cannot
  rely on RRS to inform MQ to back out the associated Unit of
  Recovery.
  
  MQ must automatically perform this backout, preventing the
  messages from being left uncommitted on the queue.
  

Problem conclusion

• Processing has been amended to ensure the the transaction is
  correctly backed-out as necessary.
  010Y
  100Y
  CSQMCTXE
  CSQ3RRSR
  

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:

  PI26626 UI21872 UI21873

Modules/Macros

• CSQMCTXE CSQ3RRSR
  

Fix information

• Fixed component name

  WMQ Z/OS V7

• Fixed component ID

  5655R3600

Applicable component levels

• R010 PSY UI21872

     UP14/10/17 P F410 ¢

• R100 PSY UI21873

     UP14/10/17 P F410 ¢

Fix is available

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