IT32639: JMS ConnectionFactory property CNLIST does not work in Apache Tomcat

APAR status

• Closed as program error.

Error description

• A JMS connection factory has been defined within Apache Tomcat,
  and uses the CNLIST property to specify a connection name list
  to connect to a multi-instance queue manager, as shown below:
  
    < Resource name="jms/ConnectionFactory"
         auth="Container"
         CHAN="CHANNELNAME"
         QMGR="QMGRNAME"
         CNLIST="Host1(2000),Host2(2000)"
         ... ...>
  
  However, when an application uses the connection factory to
  create a connection, a JMSException containing the following
  message is thrown:
  
  JMSWMQ0018: Failed to connect to queue manager 'QMGRNAME' with
  connection mode 'Client' and host name 'localhost(1414)'.;
  nested exception is com.ibm.mq.MQException: JMSCMQ0001: IBM MQ
  call failed with compcode '2' ('MQCC_FAILED') reason '2538'
  ('MQRC_HOST_NOT_AVAILABLE').
  

Local fix

• Specify the connection name list using the property CRSHOSTS,
  instead of CNLIST.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects users of the IBM MQ classes for JMS that:
  
  - Have defined JMS connection factories in Apache Tomcat, where
  the connection factory definition contains the CNLIST
  (Connection name list) property.
  - And have applications running inside Apache Tomcat which use
  that connection factory to connect to a queue manager.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  When an MQ connection factory is stored in a JNDI repository,
  the MQ classes for JMS will:
  
  - Construct a javax.naming.Reference object containing a number
  of name/value pairs representing the properties of the factory.
  - And pass the Reference object to the JNDI provider to be
  stored in the repository.
  
  When the connection factory is looked up from JNDI, the JNDI
  provider passes the Reference back to the MQ classes for JMS.
  The MQ classes for JMS read the properties contained within the
  Reference to rebuild the MQ connection factory for the
  application to use.
  
  Now, the Connection Factory property CNLIST (Connection name
  list) allows users to specify a comma-separated list of
  "hostname(port)" pairs, where each pair contains:
  
  - The hostname of the system where the queue manager is running.
  - And the port that the listener associated with that queue
  manager is using.
  
  In most environments, when this property is set on a connection
  factory, the MQ classes for JMS create a new internal property
  on the connection factory called CRSHOSTS, and set its value to
  the same value of the CNLIST property. The CRSHOSTS property is
  then added to the Reference object that is stored in JNDI. When
  the MQ classes for JMS reconstruct the connection factory from
  the Reference, they check if the CRSHOSTS property has been set
  - if it has, then the connection name list for the factory is
  set to the value of CRSHOSTS. If it has not been set, then the
  connection name list property is left at its default value of
  "localhost(1414)".
  
  However, when an MQ connection factory was defined with Apache
  Tomcat, it was possible that the Reference object stored in JNDI
  had the CNLIST property set on it, rather than CRSHOSTS. In this
  situation, when the MQ classes for JMS rebuilt the connection
  factory from the Reference, the connection name list was not set
  on it. As a result, when an application created a JMS connection
  from the connection factory, the MQ classes for JMS tried to
  connect to an instance of the queue manager running on the
  system with hostname "localhost" and using port 1414. This
  attempt failed and a JMSException containing the following
  message was thrown back to the application:
  
  JMSWMQ0018: Failed to connect to queue manager '<queue manager
  name>' with connection mode 'Client' and host name
  'localhost(1414)'.;
  nested exception is com.ibm.mq.MQException: JMSCMQ0001: IBM MQ
  call failed with compcode '2' ('MQCC_FAILED') reason '2538'
  ('MQRC_HOST_NOT_AVAILABLE').
  

Problem conclusion

• The MQ classes for JMS have been updated so that when a
  Reference object representing an MQ connection factory is
  retrieved from a JNDI repository, the following steps will now
  be performed:
  
  - Initially check to see if the Reference contains the CRSHOSTS
  property.
  - If it does:
      - Set the connection name list to the value of CRSHOSTS.
  - Else if the Reference contains the CNLIST property then:
      - Set the connection name list to the value of CNLIST.
  - End if
  
  This ensures that the connection name list will be set on an MQ
  connection factory, if the Reference object looked up from JNDI
  uses either the CNLIST or CRSHOSTS property to store this
  information.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.1 CD    TBC.
  v9.1 LTS   9.1.0.7
  
  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 MP

• Fixed component ID

  5724H7271

Applicable component levels