WebSphere Extended Deployment, Version 6.0.x
             Operating Systems: AIX, HP-UX, Linux, Solaris, Windows, z/OS


Configuring HTTP session affinity in the on demand router

About this task

In most cases, the on demand router (ODR) does not require configuration to support HTTP session affinity. However, some special cases exist where you must configure the ODR:

Procedure

  1. Create and modify the session affinity descriptor. In the administrative console, click Servers > Dynamic clusters or Generic server clusters > cluster_name> Custom properties > New.
  2. Define the session affinity descriptor properties. Create a custom property to define the session affinity descriptor. Enter the name of the custom property as HttpSessionAffinityPolicyDescriptor. The value must be in the following format:
    <learnCloneIDs>!@#<cookieNames>!@#<urlRewriteNames>!@#<delimiter>
    • <learnCloneIDs>: The value of this field must be either true or false'. If the value is true, the ODR will look at the clone IDs returned in responses from individual servers in order to learn the clone IDs of those servers. This is only necessary when the servers are non-WebSphere or the ODR is not in the same core group as that of the application servers and the core groups are not bridged together.
    • <cookieNames>: The value of this field is a comma-separated list of cookie names which are used to determine if a request has affinity. Modify this field if an application uses non-standard cookie names.
    • <urlRewriteNames>: The value of this field is the name of the field used in a URL when affinity is kept using URL-rewriting.
    • <delimiter>: The value of this field is separator character or string used to extract the clone ID from the cookie value. For example, the standard WebSphere cookie value is of the form '<sessionID>:<cloneID>' where the ':' character is the delimiter.
    • The default value of the HttpSessionAffinityPolicyDescriptor custom property is:
      false!@#WSJSESSIONID,JSESSIONID,SSLJSESSIONID!@#jsessionid!@#:
      The false value indicates that clone IDs are learned directly from the servers, not by parsing responses. The WSJSESSIONID,JSESSIONID,SSLJSESSIONID value causes the ODR to look for three different cookie names to find session information, and then jsessionid in the URL. When extracting clone IDs from the session information, the : delimiter character is used.

Results

When the ODR processes a request, it obtains the session affinity descriptor policy that is configured for the cluster to which the server belongs. The method in which the server clone identification is obtained depends on the property values of the policy attributes.




Related concepts
Overview of request flow prioritization
Related tasks
Creating ODRs
Routing requests to external nodes with generic server clusters
Creating and configuring ODRs
Task topic    

Terms of Use | Feedback

Last updated: Oct 16, 2009 11:06:12 AM EDT
http://publib.boulder.ibm.com/infocenter/wxdinfo/v6r0/index.jsp?topic=/com.ibm.websphere.xd.doc/info/odoe_task/todrpassive.html