PH34977: INTELLIGENT MANAGEMENT ENABLED PLUGIN ATTEMPTS TOO MANY RETRIES WHEN APPLICATION WITH SESSION AFFINITY RETURNS 503.

APAR status

• Closed as program error.

Error description

• Intelligent Management enabled Plugin attempts too many retries
  when application with session affinity returns 503.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server                                      *
  *                  using Intelligent  Management Enabled Web   *
  *                  Servers                                     *
  ****************************************************************
  * PROBLEM DESCRIPTION: For an affinity application attempting  *
  *                      to return a HTTP 503 to their client,   *
  *                      delays may be observed.                 *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  In the plugin's log it can be seen that retries are made for the
  same server equal to the number of endpoint in the odrGroup.
  The
  informational message 'http.summary' including
  'RESPONSE_READ_ERROR Retry' for the same endpoint will be
  observed.
  

Problem conclusion

• One fix and two improvements have been made.  First affinity
  will be broken and retires will only be made up to the number of
  endpoints able to service the request.  Two tune-able properties
  have been added to allow custom limiting of the amount of
  retries.  The first of these, 'MaxTargetEndpointsPerRequest',
  globally limits the number of attempts for a request for any
  reason.  Acceptable values for this property are 1 or more.  The
  second of these, 'Request503Retry', globally limits the number
  of retries Http 503 responses from the application servers. The
  acceptable values for this property are 0 or more.
  
  The fix for this APAR is targeted for inclusion in fix pack
  8.5.5.20 & 9.0.5.8. For more information, see 'Recommended
  Updates for
  WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

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

  WEBS APP SERV N

• Fixed component ID

  5724H8800

Applicable component levels

• R850 PSY

     UP

• R900 PSY

     UP