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IT05296: WMQ 8.0 MQTT CHANNEL SUDDENLY STOPS WITH NULL POINTER EXCEPTIONS

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • With WebSphere MQ 8.0, MQTT channel stops to work suddenly. FDC
    files are generated with the following function stack:
    
    Cause:1 :- java.lang.NullPointerException
    StackTrace:1 :- java.lang.NullPointerException
        at
    com.ibm.mq.MQXRService.MQTTServerSession.scheduleAsynchronousWor
    k(MQTTServerSession.java:1567)
       at
    com.ibm.mq.MQXRService.MQTTServerSession.scheduleCompleteConnect
    ion(MQTTServerSession.java:1605)
       at
    com.ibm.mq.MQXRService.MQTTServerSession.doAsynchronousWork(MQTT
    ServerSession.java:1319)
       at
    com.ibm.mq.MQXRService.MQTTServerSessionV3.doAsynchronousWork(MQ
    TTServerSessionV3.java:1621)
       at
    com.ibm.mq.MQXRService.MQTTServerContext.doAsynchronousWork(MQTT
    ServerContext.java:191)
        at
    com.ibm.mq.communications.NonBlockingWorker.synchronousWorkCompl
    eted(NonBlockingWorker.java:633)
       at
    com.ibm.mq.communications.NonBlockingWorker.run(NonBlockingWorke
    r.java:421)
        at java.lang.Thread.run(Thread.java:804)
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    This issue affects users of the WebSphere MQ MQXR service with
    large numbers of client performing connection takeovers.
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    There was a timing issue where if a client with a specific ID
    reconnected from a different address, the takeover of the
    connection could fail due to there being a small timing window
    where an internal variable could be null.
    

Problem conclusion

  • There is a check to confirm this internal variable is not null,
    and the NullPointerException does not occur.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v8.0       8.0.0.2
    
    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 number

    IT05296

  • Reported component name

    WMQ MOBILITY

  • Reported component ID

    5724H7258

  • Reported release

    800

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2014-10-31

  • Closed date

    2014-11-28

  • Last modified date

    2014-11-28

  • 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 MOBILITY

  • Fixed component ID

    5724H7258

Applicable component levels

  • R800 PSY

       UP

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"8.0","Edition":"","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]

Document Information

Modified date:
28 November 2014