I tried a few things and this is what I found. I did try adding a third node (using a virtual machine) and I still see the issue so I removed it.
Using my existing domain, node-agents, virtual machine, Apache mod proxy, etc., I switched to a "file" realm from my JDBC realm (still using my current application), and I still see the issue.
I then undeployed my application and deployed the clusterjsp.ear. I refreshed the page many times using the refresh in Firefox and using the refresh button on the jsp, and the session stayed the same. I did this for several minutes and was pretty much giving up. Then as I was writing this I tried it again and after a little while I saw the session ID change. I went on refreshing for several minutes trying to make it happen again. Then I tried refreshing as fast as I could and still didn't see it happen again. Then I simply held down the F5 key to have the "key repeat" send as fast as possible, and I saw the problem. I then restarted all the glassfish parts, just for grins and got it to demonstrate the problem again by holding down the refresh key F5.
I'm still using Apache mod proxy, and a Virtual machine but I don't really think those are the issue. I can use another physical machine pretty easy so I'll try that also, but I think you might be able to create the same issue in your environment by sending the refreshes as quickly as possible.
My application is fairly good size and does use frames and creates many server hits for each page transition so this does make some sense from that point of view. Let me know what you think and if you have any suggestions with configuration or anything. Thanks for your help.
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