PH06227: MQ Z/OS: APPLICATION HUNG WHEN ASYNC CONSUMER IS USED WITH A QSG

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• MQ z/OS
  application hung when async consumer is used with a QSG
  
  There is an issue with the way the async consumer is set up
  when the application is connected to a QSG and there is more
  than one member available on the LPAR.
  
  When an async consumer is established, a new thread is created
  which is where the callback processing will run.
  This additional thread needs to be connected to the same qmgr as
  the application thread, so that it can use the queue handle
  which  it has already been opened.
  If the application thread is connected using the QSG name, the
  connect
  logic for the async thread is incorrectly connected using the
  QSG name.
  If there are two or more members of the QSG on the same LPAR,
  this means
  that the async thread can end up connected to a different qmgr
  from the
  application thread.
  

Local fix

• na
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM MQ for z/OS Version 8       *
  *                 Release 0 Modification 0.                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: MQ Z/OS: APPLICATION HUNG WHEN ASYNC    *
  *                      CONSUMER IS USED WITH A QSG             *
  ****************************************************************
  When an async consumer is established, a new thread is created
  which is where callback processing will run. This additional
  thread needs to be connected to the same qmgr as the application
  thread, so it can use the queue handle which has already been
  opened.
  If the application thread is connected using the QSG name,
  the  connect logic for the async thread is incorrectly
  connecting using the QSG name.
  If there are two or more members of the QSG on the same LPAR,
  this means that the async thread can end up connected to a
  different qmgr from the application thread.
  

Problem conclusion

• The CSQBCON module has been updated with corrective conditional
  logic to ensure the application threads connect appropriately.
  

Temporary fix

Comments

APAR Information

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

  PH06033

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

  UI63845

Modules/Macros

• CSQBCON
  

Fix information

• Fixed component name

  IBM MQ Z/OS V8

• Fixed component ID

  5655W9700

Applicable component levels

• R000 PSY UI63845

     UP19/07/23 P F907

Fix is available

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