IT45035: MQ 9.2.4 or later client pub/sub app cannot consume messages after reconnecting following a connection break

APAR status

• Closed as program error.

Error description

• The problem has been replicated using the amqsevt sample, run as
  follows with the "-r r" flag.
  
  /opt/mqm/samp/bin/amqsevt -m TEST -c -r r -t myTopic/testTopic
  
  After a network break, it is expected that a reconnectable
  client application should reconnect and continue to display
  messages published to the myTopic/testTopic topic. However with
  amqsevt, after the break, new messages no longer appear in the
  terminal. Other reconnectable MQ client applications may
  similarly not receive newly published messages after a network
  break.
  
  Queue manager traces confirmed the messages are published and
  consumed but not being displayed to the terminal.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  MQ 9.2.4 CD and later releases, including 9.3.0.x LTS,
  reconnectable client applications using publish subscribe
  messaging.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A regression was introduced into the MQ library code running
  within the application program, causing subscription messages
  not to be delivered to the application, after a network break or
  fail-over event.
  

Problem conclusion

• The MQ code has been corrected.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.3 LTS   9.3.0.20
  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://ibm.biz/mqplannedmaintenance
  
  ---------------------------------------------------------------
  

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 APPLIANCE M2

• Fixed component ID

  5900ALJ00

Applicable component levels