IT44173: MQSUB fails to automatically reconnect with 2548: MQRC_RECONNECT_FAILED

APAR status

• Closed as program error.

Error description

• When an MQSUB call loses connection with a queue manager,
  auto-reconnect logic should attempt to restore the connection
  and allow the MQSUB to reconnect.
  
  However a timing window meant that this could fail with error
  code 2548: MQRC_RECONNECT_FAILED and cause the subscriber to
  disconnect.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of Publish/Subscribe messaging with auto-reconnects
  enabled.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A timing window in the auto-reconnect logic caused subscriptions
  to be incorrectly marked as in use, causing the reconnect to
  fail.
  

Problem conclusion

• Corrected the logic to check if subscription is still in use and
  removed automatic sub reconnect during edge cases.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.3 LTS   9.3.0.15
  v9.x CD    9.3.5
  
  The latest available maintenance can be obtained from
  'IBM MQ Recommended Fixes'
  https://www.ibm.com/support/pages/recommended-fixes-ibm-mq
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'IBM MQ
  Planned Maintenance Release Dates'
  https://www.ibm.com/support/pages/ibm-mq-planned-maintenance-rel
  
  ---------------------------------------------------------------
  

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:

Fix information

• Fixed component name

  MQ BASE V9.3

• Fixed component ID

  5724H7291

Applicable component levels