IT26614: MQ dotnet (.NET) client channel ends abnormally when the heartbeat (HBINT) is reached

APAR status

• Closed as program error.

Error description

• MQ V9 .dotnet client channels end abnormally when the heartbeat
  interval (HBINT) on the channel is reached.
  
  The queue manager error logs record the following at the
  intervals for the configured HBINT:
  --------------------------------------------------------
  10/11/2018 01:42:20 PM - Process(xxxx.xxx) (mqm)
             Program(amqrmppa)
             Host(TestHost) Installation(Installation3)
             VRMF(x.x.x.x) QMgr(TEST)
  AMQ9999: Channel 'TEST.SVRCONN' to host 'x.x.x.x'
            ended abnormally.
  EXPLANATION:
  The channel program running under process ID xxxx for
   channel 'TEST.SVRCONN'
  ended abnormally. The host name is 'x.x.x.x.'; in some
  cases  the host name cannot be determined and so is shown
  as '????'.
  ACTION:
  Look at previous error messages for the channel program in
  the error logs to determine the cause of the failure.
  Note that this message can be excluded completely or
  suppressed by tuning the "ExcludeMessage" or
  "SuppressMessage"  attributes under the QMErrorLog"
  stanza in qm.ini. Further  information can be found in
  the System Administration Guide.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  All users of a managed .NET application.
  
  
  Platforms affected:
  Windows
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  MQ managed .NET client sends a heartbeat if it does not receive
  any data from the queue manager until the time set in the
  channel heartbeat expires. After sending the heartbeat, the
  client waits for a response from the Queue Manager.  If no
  response is received before the receive timeout value expires
  then the channel is closed by the client.
  
  Since the receive timeout value was incorrectly calculated in
  milliseconds instead of seconds, the channel is closed much
  sooner than a response is received from the server.
  
  Additionally, a coding error meant that a default HBINT of 300
  was proposed to the queue manager by the MQ managed and
  unmanaged .NET client. If this value was higher than the HBINT
  on the SVRCONN channel, then the queue manager would accept this
  value.
  A logic error when negotiating the HBINT value caused the
  connection attempt to be aborted at the client side with
  MQRC_Q_MGR_NOT_AVAILABLE in the following cases:
  
  When using CCDT, if HBINT of CLNTCONN  is set less than SVRCONN
  HBINT
  
  When not using CCDT, if HBINT of SVRCONN is greater 300.
  

Problem conclusion

• The MQ managed .NET client has been modified to correctly set
  the receive timeout interval in seconds instead of milliseconds
  so that the client waits for the correct receive timeout
  interval.
  
  The MQ managed and unmanaged .NET client has also been modified
  to use the HBINT from the SVRCONN channel definition when
  establishing a connection to the queue manager if a CCDT is not
  being used.
  
  A logic error when negotiating the HBINT value caused the
  connection attempt to be aborted at the client side with
  MQRC_Q_MGR_NOT_AVAILABLE in the following cases:
  
  When using CCDT, if HBINT of CLNTCONN  is set less than SVRCONN
  HBINT.
  
  When not using CCDT, if HBINT of SVRCONN is greater than default
  HBINT of client(300).
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.13
  v9.0 LTS   9.0.0.7
  v9.1 CD    9.1.3
  v9.1 LTS   9.1.0.3
  
  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:

Fix information

• Fixed component name

  IBM MQ BASE M/P

• Fixed component ID

  5724H7261

Applicable component levels