The following topology has been built: cell with cluster comprised of two WAS servers. Nodes belong to "ReplicationZone" Node group. There is XC10 appliance ver 1.0 in the mix. On the application level Session management is enabled and session persistence is provided by DataPower XC10 appliance.
The sample application is session-aware with counter stored in the session object. The app comprised of login servlet, couple "worker" servlets and logoff servlet to invalidate session.
I use JMeter to run application. I can see Grid to be populated at runtime and I know that both my servers are load-balanced by HTTP server as I can see each of them serve the requests generated by JMeter.. No memory-to-memory replication is set up.
Obviously, what I want to see is the session failover. While app is running in JMeter loop (worker servlets are invoked every 2-3 seconds), one of the servers gets shut down. I expect to see the second server to pickup new requests and reuse session data persisted in the appliance. Unfortunately I just see the session dropped – as if no replication is setup. What else is needed to be setup so sessions will survive the server shutdown?
Pinned topic How to use DataPower XC10 for session persistance/failover?
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Updated on 2011-03-16T21:09:11Z at 2011-03-16T21:09:11Z by bkmartin
bkmartin 120000K38911 Posts
Re: How to use DataPower XC10 for session persistance/failover?2011-03-13T01:45:41ZThis is the accepted answer. This is the accepted answer.Are you running XC10 firmware 22.214.171.124 with the XC10 Client 1.0 (XS 126.96.36.199) updated on 12/17/2010 posted here: http://www-01.ibm.com/support/docview.wss?uid=swg24027148
There is nothing special you need to do to enable session failover as long the application is configured to use the XC10 for session persistence in the WAS WebUI. What version of WAS is being utilized? Are you using the WAS plugin as the front end load balancer for this scenario?
I suspect we might need to look at session=all=enabled traces on your WAS servers to see why you are not seeing the sessions failover from WAS server to the other.
SystemAdmin 110000D4XK25 Posts
Re: How to use DataPower XC10 for session persistance/failover?2011-03-14T20:00:06ZThis is the accepted answer. This is the accepted answer.Thank you, Brian for response.
As soon as I bounced the servers I can see the session failover working.
The next related question is why I don't see sessions coming back to the initial server.
Here is the scenario:
Two WAS servers fronted with IHS. Two browser-based clients access the application deployed to the cluster. Each client is served by one of servers. I cat track this using com.ibm.websphere.runtime.ServerName. Session affinity works fine.
Now I take down one server and can see that all requests are served by the remainin server. The expected behavior (I may be wrong here drawing parallels with memory-to-memory replication) whould be that when I bring up the failed server back the session initially hosted on that server would come back. I don't see this happening. After session failed over to another server it does not come back to the server where it was started. Is this correct behavior?
bkmartin 120000K38911 Posts
Re: How to use DataPower XC10 for session persistance/failover?2011-03-16T21:09:11ZThis is the accepted answer. This is the accepted answer.
- SystemAdmin 110000D4XK