IT17062: Change subscription with no parameter causes subtype change fromproxy to admin created FDC with probe ID PS000085

APAR status

• Closed as program error.

Error description

• When a user alters an subscription with SubType of PROXY (using
  the subId to identify it) MQ alters the SubType of the
  subscription to ADMIN in keeping with the documentation
  This helps indicate that an API subscription created by an
  application for example, has been changed.
  
  For a PROXY subscription however, this causes issues :
  - After a queue manager restart, additional PROXY subscriptions
  are created on behalf of the 'new' ADMIN subscriptions causing
  un-intended traffic.
  - Publications received by remote queue managers, are not
  processed correctly
  
  The fdc is reported as :
  | Probe Id          :- PS000085
  | Component         :- psiReceivePublications
  
  | Program Name      :- amqzmuf0
  | Major Errorcode   :- MQRC_PROPERTY_NOT_AVAILABLE
                +
  MQM Function Stack
  psiReceivePublications
  xcsFFST
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of Queue Manager Clusters Publish / Subscribe who
  inadvertently make alterations to proxy subscriptions using the
  subid attribute to reference a subscription
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  Secondary proxy subscriptions were created when a queue manager
  is recycled having altered an existing proxy subscription (with
  no specific changes to simply force persistence to the
  SYSTEM.DURABLE.SUBSCRIBER.QUEUE)
  
  The secondary proxy subscriptions can cause duplicate
  publications to remote queue managers which cannot be processed
  correctly.
  

Problem conclusion

• The problem is resolved with the inclusion of a check of the
  subscription type, before allowing the alteration to take place.
  If a user attempts to change an internal proxy subscription, the
  command will now fail reporting MQRC_SUBSCRIPTION_IN_USE
  (AMQ8469)
  Applications using Programmable Command Formats (PCF) to alter
  internal proxy subscriptions, will receive return code
  MQRCCF_SUBSCRIPTION_IN_USE
  
  The following pages have been updated as a result of this APAR :
  The following pages should be considered for updates with this
  APAR ..
  
  https://www.ibm.com/support/knowledgecenter/SSFKSJ_7.5.0/com.ibm
  .mq.ref.adm.doc/q086340_.htm
  PROXY
   An internally created subscription used for routing
  publications through a queue manager.
  Subscriptions of type PROXY are not modified when to ADMIN when
  alterations are attempted
  
  http://www.ibm.com/support/knowledgecenter/SSFKSJ_8.0.0/com.ibm.
  mq.ref.adm.doc/q085420_.htm
  Usage notes for ALTER SUB : Added point 4.
  Subscriptions with SUBTYPE of PROXY, cannot be modified.
  Attempting to do so using the PCF interface, will return
  MQRCCF_SUBSCRIPTION_IN_USE
  MQSC will report the following message
   	AMQ8469: WebSphere MQ subscription SYSTEM.PROXY in use.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.6
  v9.0 CD    9.0.2
  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 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