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High Availability Peoplesoft PeopleTools Weblogic

Load Balancing <> High Availability <> Seamless Failover

Having a load balancer and multiple Peoplesoft VM’s at the Web and App layer with a clustered database server does not guarantee “seamless failover” for the end user – it all depends how it is all configured.

Here’s a nice example:

  • Load Balancers (x2 actually)
  • Multiple Weblogic servers
  • Multiple Application servers
  • Clustered DB server

The load balancer feeds the Weblogic servers with sessions and maintains “session stickiness” via a cookie. They in turn each know about the application servers so they can load balance across them too. All good? Nope.

Hmmm … the Weblogic servers are single server domains. With different session cookie names.

So, if a Weblogic server fails the load balancer will re-direct the session to another one. But that server is not even looking for the same session cookie name. End result for the users … the PeopleSoft login page.

But even if all the Weblogic servers did share the cookie name we have another problem – there is no session replication between the Weblogic servers as they were configured as single server domains. No Coherence, no wl_sessions table in a DB somewhere – nothing. End result for the users … the PeopleSoft login page.