> upgrades for applications that maintain state - since a user might > have a session created using a new-code box, then hit an old-code box > on the next page view. it takes us many minutes to work through > restarting the entire array. > > were you ever concerned about something like that?
I only learned this yesterday by reading Perrin's eToys article, but their concept of sticky load balancing was interesting. They had a proxy server in front of the app servers. The proxy assigned session keys, and made sure that if you came back in on the same session you got assigned to the same app server. I thought that was a neat idea and would solve this particular problem. -Fran
