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The moose likes BEA/Weblogic and the fly likes Session Replication Big Moose Saloon
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Session Replication

PN Kumar
Ranch Hand

Joined: Sep 08, 2001
Posts: 38
In Weblogic 8.1 server, at which point of time does session replication actually take place.For instance, suppose there are 3 servers in a group(across systems), and requests from a particular client go to server1.What i understand from clustering is that the session gets replicated to server2 and server3 - when actually does it take place? Is it during each request - if so wont there be an unnecessary overhead? Or is it during failure of server1 - in which case, how come the session in server1 gets replicated after server1 fails?
Sathwik BP

Joined: Mar 04, 2004
Posts: 2
In a cluster env, replication happens when a value is bound or unbound from the Session/ServletContext objects.
This happens every time, when an object is bound or unbound, and yes this could be a performance issue, considering that the amount of data that is stored in the Session/ServletContext objects.
Rob Misek
Ranch Hand

Joined: Sep 24, 2002
Posts: 41
Further, I am pretty sure that WebLogic follows a primary and secondary modeal for session replication so the session is not replicated to _both_ server2 and server3, just one of them.

<a href="" target="_blank" rel="nofollow"></a><br /><a href="" target="_blank" rel="nofollow">Coherence:</a> Easily share live data across a cluster!
It is sorta covered in the JavaRanch Style Guide.
subject: Session Replication