IBM Support

IT16872: MQ can incorrectly handle internal object reference count value during media backup

Subscribe to this APAR

By subscribing, you receive periodic emails alerting you to the status of the APAR, along with a link to the fix after it becomes available. You can track this item individually or track all items by product.

Notify me when this APAR changes.

Notify me when an APAR for this component changes.

 

APAR status

  • Closed as program error.

Error description

  • A queue file might disappear from the object catalog resulting
    in a queue not being visible to
    RUNMQSC or MQ Explorer.
    An earlier set of FDCs can display a pattern similar to the
    following:
    amqzlaa0    XC027010
    xcsRequestMutexSem      STOP OK
    amqzlaa0 AO175000 aouLockQHandle          STOP OK
    amqzlaa0 AO254010 aocDeregisterQHandleUse STOP OK
    
    The problem is fully diagnosed using a temporary patch from the
    MQ L3 service team.
    The diagnostic patch shows:
    An FDC with probID AO254010 and function name
    aocDeregisterQHandleUse
    MQM Function Stack
    zlaMainThread
    zlaProcessMessage
    zlaProcessSPIRequest
    zlaSPIRecordImage
    zsqSPIRecordImage
    kpiSPIRecordImage
    apiRecordMediaImage
    aomRecordMediaImage
    aocDeregisterQHandleUse
    xcsFFST
    The body of the FDC shows:
    AOCDetail
    {
    Qid 3B16FF49.11F
    DiskOffset 406
    RealName queues/<QNAME>
    Flags aocOBJFLAG_ATTRS_DISK
    ModelQid 0.0
    ReuseCount 0
    ReferenceCount 18
    RefCountByType[0] 14
    RefCountByType[1] 1
    RefCountByType[2] 0
    RefCountByType[3] 0
    RefCountByType[4] 2
    RefCountByType[5] 0
    RefCountByType[6] 0
    RefCountByType[7] 0
    RefCountByType[8] 0
    RefCountByType[9] 0
    RefCountByType[10] 0
    RefCountByType[11] 0
    RefCountByType[12] 1
    RefCountByType[13] 0
    RefCountByType[14] 0
    RefCountByType[15] 0
    QState         0X2
    BestBeforeTime 0
    IdleCount 0
    EmptyCount 0
    UseCountOC 2441754
    UseCountQL 2441753
    LogReserve 0
    RecoveryFlags: None
    {
    Qid          : 3b16ff49.ffffffff
    hsmbQHandle  : 2.11.11.5904000
    } Synonym
    {
    Qid          : 3b16ff49.11f
    hsmbQHandle  : 2.11.11.5904000
    } SynonymO
    }
    
    The important values in the output are ReferenceCount and
    RefCountByType.
    The RefCountByType array has been added as part of the
    diagnostic.
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    Users of IBM MQ V8.0 and later.
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    The IBM MQ administration utility rcdmqimg had the potential to
    incorrectly set an internal reference count for a queue. This
    caused a problem at a later time with the queue being
    incorrectly marked as deleted.
    

Problem conclusion

  • The IBM MQ functions which handle rcdmqimg have been modified to
    correctly handle the internal reference count.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v8.0       8.0.0.6
    v9.0 CD    9.0.1
    v9.0 LTS   9.0.0.1
    
    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

    IT16872

  • Reported component name

    WMQ BASE MULTIP

  • Reported component ID

    5724H7251

  • Reported release

    800

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2016-09-01

  • Closed date

    2016-10-05

  • Last modified date

    2017-06-01

  • 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 BASE MULTIP

  • Fixed component ID

    5724H7251

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":"8.0.0.0","Edition":"","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]

Document Information

Modified date:
01 June 2017