A question about load balancers and Terracotta clustering

[Wessel, Keith William]

I know quite a few of you out there have Shib clustered using Terracotta behind a load balancer. We're in the process of moving our production cluster from round robbin DNS to actual, real hardware load balancing. (much to my and many other folks' relief).

I'm doing some testing with our test cluster, and I'm noticing something odd. As recommended, we're running a Terracotta cluster node on each of our two IDP nodes. I'm logging into a test SP then restarting shibd and Apache to force reauthentication when I refresh the SP webpage in the browser. Before refreshing, I'll shut down the IDP node that I used to log in the first time. I'll then wait for Terracotta output on the other IDP to say it's taken over as the active node. In theory, if my persistent store and the Terracotta cluster is working, it'd seem my IDP session would still be valid. Session lifetime on the IDP has been left at the default 30 minutes. However, I'm getting the login screen from the other IDP node at this point.

So, if I lost anyone:

1.      Log into SP via Shib node 1

2.      Once logged in and back at the SP, shut down Tomcat and Terracotta on Shib node 1.

3.      Restart shibd and Apache on the SP.

4.      Click refresh in the browser which takes me to Shib node 2 via the load balancer

5.      Instead of having my existing session honored, I'm getting a login screen.
FYI, I don't get the login screen if I just restart shibd and Apache then hit the same IDP node again that I hit the first time, so I know the SP isn't doing forced re-auth.

Am I overlooking something here? Is this working as designed? Or does it seem I have a Terracotta misconfiguration somewhere?

Thanks for any help that anyone can offer.

Keith

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://shibboleth.net/pipermail/users/attachments/20120628/9b267908/attachment-0001.html