PM52728: WEBSPHERE SIP CONTAINER DISCARDS THE CANCEL IN RACE CONDITION

APAR status

• Closed as program error.

Error description

• We have a race condition, which occurs when we sent a reliable
  interim response (i.e. a response expecting a PRACK) on our
  incoming leg just as the incoming leg is sending a CANCEL.  The
  behavior we see is that Websphere discards the CANCEL in this
  case   not passing it to the application code.  No PRACK is ever
  sent from the incoming leg, since the other side of the dialog
  thinks that dialog is terminated, having sent a CANCEL.
  

Local fix

• N/A
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All SIP container users of IBM WebSphere    *
  *                  Application Server                          *
  ****************************************************************
  * PROBLEM DESCRIPTION: SIP Cancel request is not sent to the   *
  *                      application                             *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When 200 OK response for Cancel is received after reliable
  response it is discarded by the SIP container.
  

Problem conclusion

• SIP container has been modifed to not discard 200 OK response
  on Cancel after reliable response.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  PM52359

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  CEA FEATUREPACK

• Fixed component ID

  5655N0255

Applicable component levels

• R700 PSY

     UP