IT00663: WMQ V7.1 AND V7.5: CLIENT APPLICATIONS MAY RECEIVE MQRC=2009 (MQRC_CONNECTION_BROKEN) ON MQGET CALLS.

Fix Pack 7.1.0.6 for WebSphere MQ V7.1

APAR status

• Closed as program error.

Error description

• When a client application disconnects and reconnects to a queue
  manager, the application may fail to receive messages and an
  MQRC_CONNECTION_BROKEN may be returned to the application.
  
  From a WebSphere MQ trace taken on the queue manager side, it
  can be seen that an MQCTL call ends with reason 2534
  (MQRC_OPERATION_NOT_ALLOWED).
  As result the qmgr sends STREAMING_FAILURE error to the client
  application and terminates the connection.
  
  Here is an abstract of the WebSphere MQ trace:
  
   ----------}! lpiSPICTL (rc=MQRC_OPERATION_NOT_ALLOWED)
   MQCTL(SUSPEND) failed CC(2) RC(2534)
   ----------{ rrxError
   .
   .
   .
   ----------}! rstSuspendConnection (rc=rrcE_MQAPI_FAILED)
   ---------}! rstReceiveMessageRequest (rc=rrcE_MQAPI_FAILED)
   --------}! rriServerAsyncRcv (rc=rrcE_MQAPI_FAILED)
   pHdr<027F46F8> Decremented UseCount(1)
   -------}! cciProcessAsyncRcv (rc=rrcE_MQAPI_FAILED)
   ------}! cciProcessUserData (rc=rrcE_MQAPI_FAILED)
   -----}! cciProcessOne (rc=rrcE_MQAPI_FAILED)
   -----{ ccxPoolFree
   ------{ xcsRequestThreadMutexSem
   ------} xcsRequestThreadMutexSem (rc=OK)
   ------{ xcsReleaseThreadMutexSem
   ------} xcsReleaseThreadMutexSem (rc=OK)
   -----} ccxPoolFree (rc=OK)
   -----{ xcsQueryThreadMutexSem
   hmtx is
   -----} xcsQueryThreadMutexSem (rc=OK)
   -----{ cciEndConv <-- the conversation is being ended
  

Local fix

• Set SHARECNV=0 in channel svrconn definition
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users using MQ XA client application that request messages from
  the queue manager.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  When an XA client application failed to disconnect cleanly, so
  state information was not correctly cleaned up within the queue
  manager. This meant that if the application reconnected and
  re-issued the request, the queue manager logic incorrectly
  assumed that the request was part of the previous connection and
  hence, failed with MQRC_CONNECTION_BROKEN error.
  

Problem conclusion

• The queue manager logic has been modified to correctly
  update the session data when the connection disconnects.  This
  means that the message request made in the subsequent fresh
  connection can be processed correctly.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v7.1       7.1.0.6
  v7.5       7.5.0.5
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

Temporary fix

Comments

APAR Information

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

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

  PI17126

Fix information

• Fixed component name

  WMQ BASE MULTIP

• Fixed component ID

  5724H7241

Applicable component levels

• R750 PSY

     UP