IC62386: XASESSION.CLOSE() DOES NOT DISCONNECT FROM THE QUEUE MANAGER, EVENTUALLY LEADING TO "AMQ9513: MAX CHANNELS REACHED" ERRORS.

WebSphere MQ V7.0 Fix Pack 7.0.1.1
WebSphere MQ V7.0 Fix Pack 7.0.1.2
WebSphere MQ V7.0.1 for i5/OS Fix Pack 7.0.1.2

APAR status

• Closed as program error.

Error description

• When an application using the WebSphere MQ V7 classes for Java
  Message Service (JMS) calls XASession.close(), the underlying
  connection to the queue manager is left open.
  
  After a period of time, the application will get the following
  exception when calling XAConnection.createXASession():
  
  com.ibm.msg.client.jms.DetailedIllegalStateException:
  JMSWMQ0018: Failed to connect to queue manager '<queue manager
  name>' with connection mode '1' and host name '<hostname>'.
  Check the queue manager is started and if running in client
  mode, check there is a listener running. Please see the linked
  exception for more information.
  at com.ibm.msg.client.wmq.common.internal.Reason.
  reasonToException(Reason.java:489)
  at com.ibm.msg.client.wmq.common.internal.Reason.
  createException(Reason.java:219)
  at com.ibm.msg.client.wmq.internal.WMQSession.
  (WMQSession.java:340)
  at com.ibm.msg.client.wmq.internal.WMQXASession.
  (WMQXASession.java:81)
  at com.ibm.msg.client.wmq.internal.WMQXAConnection.
  createXASession(WMQXAConnection.java:95)
  at com.ibm.msg.client.jms.internal.JmsXAConnectionImpl.
  createXASession(JmsXAConnectionImpl.java:103)
  at com.ibm.mq.jms.MQXAConnection.
  createXASession(MQXAConnection.java:82)
  
  and the error message:
  
  AMQ9513: MAX CHANNELS REACHED
  
  will appear in the queue manager error logs.
  

Local fix

• Temporarily increase the Max Channels attribute for the queue
  manager.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects all WebSphere MQ V7 applications which use
  the classes for Java Message Service (JMS) and create XA
  Sessions.
  
  Platforms affected:
  All Distributed (iSeries, all Unix and Windows) +Java
  ****************************************************************
  PROBLEM SUMMARY:
  Consider the following code:
  
  XASession_object = XAConnection_object.createXASession();
  MQSession_object = XASession_Object.getSession();
  .... do operations with MQSessionObject here ....
  XASession_object.close();
  
  When the XASession_object is closed, the backing MQSession is
  also closed which in turn closes the underlying physical
  connection.
  
  However when we have code like this:
  
  XASession_object = XAConnection_object.createXASession();
  MQSession_object = XASession_Object.getSession();
  .... do operations with MQSessionObject here ....
  MQSession_object.close();
  XASession_object.close();
  
  the underlying physical connection is marked as closed by the
  call to MQSession_object.close() but is actually left open
  (which is valid behaviour). The subsequent call to
  XASession_object.close() checks the state of connection, finds
  it is marked as closed and so does not attempt to close it.
  

Problem conclusion

• The underlying physical connection is now closed as part of the
  call to XASession.close().
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
                     v7.0
  Platform           Fix Pack 7.0.1.2
  --------           --------------------
  Windows            U200316
  AIX                U829807
  HP-UX (PA-RISC)    U829678
  HP-UX (Itanium)    U829681
  Solaris (SPARC)    U829806
  Solaris (x86-64)   U829680
  iSeries            tbc_p700_0_1_2
  Linux (x86)        U829677
  Linux (x86-64)     U829676
  Linux (zSeries)    U829682
  Linux (Power)      U829679
  
  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

  WMQ WINDOWS V7

• Fixed component ID

  5724H7220

Applicable component levels

• R700 PSY

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