IT09411: USING A RESEQUENCE NODE IN A SUBFLOW THAT IS USED IN MULTIPLE FLOWS CONTAMINATES COLLECTION STATE

APAR status

• Closed as program error.

Error description

• If a subflow contains a resequence node, and that subflow is
  used in more than one flow, and those flows are deployed to the
  same execution group, then all of the resequence nodes will
  have the same identifier.
  This will cause them to use the same correlation id for their
  messages on the collections queue. This then causes an error
  if the flows are reloaded, redeployed or restarted. A BIP2112E
  error is seen, with the text "already exists" when the broker
  tries to restart the flows.
  

Local fix

• Use copies of the subflow for each instance of their reuse.
  Each subflow should give the resequence node a different name.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  All users of IBM Integration Bus V9.0 and V10.0 who use the
  Resequence node in a subflow and reuse that subflow in more than
  one message flow.
  
  
  Platforms affected:
  z/OS, MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The Resequence node creates an identification string that it
  uses for the correlation ID of any messages that it stores to
  the collections state queue. This identification string is
  generated from information that includes the message flow name.
  
  When the Resequence node is in a subflow, the flow name only
  includes the subflow part of the name. This means that when the
  subflow is reused across more than one message flow, each
  instance of the Resequence node will have the same correlation
  ID.
  
  This becomes a problem when the Resequence nodes are
  reinitialized (by restarting the Integration bus, reloading the
  Integration server or redeploying the flow or application). Each
  of the Resequence nodes will see the collections from all of the
  other nodes.
  
  This will cause an error message to be written to the syslog
  such as BIP2112E, containing the error text "already exists".
  
  There are a number of resource name changes between WebSphere
  Message Broker and IBM Integration Bus Version 9.0. For details
  visit
  http://pic.dhe.ibm.com/infocenter/wmbhelp/v9r0m0/topic/com.ibm.e
  tools.mft.doc/bb23814_.htm
  

Problem conclusion

• The product has been changed so that each individual Resequence
  node uses the full name of the flow (including the parent flow
  name and the subflow name) to create the identification string.
  This causes each Resequence node to have a different correlation
  ID.
  
  NOTE - This APAR will change the correlation ID used to store
  the Resequence node's messages on the collections queue. There
  must be no message sequences in flight when the fix is applied,
  as the Resequence node may not load all of the previously saved
  message sequences.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.0       9.0.0.4
  v10.0      10.0.0.2
  
  The latest available maintenance can be obtained from:
  http://www-01.ibm.com/support/docview.wss?rs=849&uid=swg27006041
  
  If the maintenance level is not yet available,information on
  its planned availability can be found on:
  http://www-1.ibm.com/support/docview.wss?rs=849&uid=swg27006308
  ---------------------------------------------------------------
  

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

  INTEGRATION BUS

• Fixed component ID

  5724J0530

Applicable component levels

• R900 PSY

     UP