IBM Support

IT27694: SVRCONN channel 'stopped' status is ignored after queue manager restart allowing clients to connect

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

  • After changing the status of an INACTIVE server-connection
    channel to 'stopped', for example via the MQSC command:
    
      STOP CHANNEL('APP1.SVRCONN') STATUS(STOPPED)
    
    a subsequent restart of the queue manager results in the
    'stopped' status being restored correctly.  A display of the
    channel status shows, correctly, as 'STOPPED':
    
      DISPLAY CHSTATUS('APP1.SVRCONN')
    
      AMQ8417: Display Channel Status details.
         CHANNEL(APP1.SVRCONN)    CHLTYPE(SVRCONN)
         CONNAME( )                             CURRENT
         STATUS(STOPPED)                   SUBSTATE( )
    
    However the stopped status is ignored when a client attempts to
    connect.
    
    It is expected that a stopped server-connection channel would
    prevent the client from connecting with the MQ reason code
    MQRC_CHANNEL_NOT_AVAILABLE (2537), even after a queue manager
    restart.
    

Local fix

  • Re-issue the STOP CHANNEL command to stop the SVRCONN channel
    after the queue manager has restarted.
    

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    This issue affects IBM MQ administrators that restart a Queue
    Manager with SVRCONN channels in the "STOPPED" state.
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    The queue manager did not set an internal "disabled" flag for
    SVRCONN channels when restoring a channel status during queue
    manager restart.  The result of this was that the stopped
    SVRCONN channel could be used to create a connection after Queue
    Manager restart.
    

Problem conclusion

  • The MQ code has been updated such that if the environment
    variable AMQ_PRESERVE_STOPPED_SVRCONNS_ON_RESTART is set (to any
    value) in the environment used to start the queue manager, then
    SVRCONN channel status records in the "STOPPED" state prevent
    clients from connecting after a queue manager restart with the
    reason code MQRC_CHANNEL_NOT_AVAILABLE (2537) until they have
    been re-enabled.
    
    This APAR will have no effect if the
    AMQ_PRESERVE_STOPPED_SVRCONNS_ON_RESTART environment variable is
    not set.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v8.0       8.0.0.15
    v9.0 LTS   9.0.0.10
    v9.1 CD    9.1.3
    v9.1 LTS   9.1.0.5
    
    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

    IT27694

  • Reported component name

    IBM MQ BASE M/P

  • Reported component ID

    5724H7261

  • Reported release

    900

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2019-01-08

  • Closed date

    2020-03-27

  • Last modified date

    2020-06-10

  • 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

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"9.0","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]

Document Information

Modified date:
11 June 2020