PH06308: WEBSPHERE WEBSERVER PLUGIN CRASHES WHEN HANDLING WEBSOCKET REQUEST IN ESI CACHE.

9.0.0.11: WebSphere Application Server traditional V9.0 Fix Pack 11
9.0.5.0: WebSphere Application Server traditional Version 9.0.5 Refresh Pack
9.0.5.1: WebSphere Application Server traditional Version 9.0.5 Fix Pack 1
9.0.5.2: WebSphere Application Server traditional Version 9.0.5 Fix Pack 2
8.5.5.17: WebSphere Application Server V8.5.5 Fix Pack 17
9.0.5.3: WebSphere Application Server traditional Version 9.0.5 Fix Pack 3
8.5.5.20: WebSphere Application Server V8.5.5.20
8.5.5.18: WebSphere Application Server V8.5.5 Fix Pack 18
8.5.5.19: WebSphere Application Server V8.5.5 Fix Pack 19
8.5.5.16: WebSphere Application Server V8.5.5 Fix Pack 16
8.5.5.21: WebSphere Application Server V8.5.5.21

APAR status

• Closed as program error.

Error description

• WebSphere webserver plugin crashes when handling websocket
  request in ESI cache.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  IBM WebSphere Application Server web        *
  *                  server plugin users                         *
  ****************************************************************
  * PROBLEM DESCRIPTION: If ESI is enabled on the webserver      *
  *                      plugin and websocket traffic is         *
  *                      cached, plugin may crash.               *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When the initial websocket request is answered from ESI cache,
  no server is selected so the next request causes a crash from
  a null server object.
  Crash stack:
  #0   serverGetWsServerIOTimeout (server=0x0, reqInfo=...)
  #1   requestGetServer (request=...)
  #2   websphereHandleRequest (reqInfo=...)
  #3   as_handler (req=...)
  

Problem conclusion

• Fix restricts the ESI cache from answering initial websocket
  requests to ensure a server is selected.
  
  The fix for this APAR is currently targeted for inclusion in
  fix pack 8.5.5.16 and 9.0.0.11.  Please refer to the
  Recommended Updates page for delivery information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  

Temporary fix

• Disable ESI caching when using websockets.
  

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

  WEBS APP SERV N

• Fixed component ID

  5724H8800

Applicable component levels

• R850 PSY

     UP

• R900 PSY

     UP