Saturday, October 22, 2005
Today we're all here, moving 50ish sites off of the blade servers that they sit on, and onto brand new servers, in a load balanced environment.
Some time ago, we decided upon and purchased two Equalizers from Coyote Point Systems. The Equalizers are implemented in the the following manor (from here):
1 Equalizer "virtual clusters" provide a single IP address to Client on Internet or Intranet.
2 Equalizer monitors server performance and availability. Client requests are forwarded to best available server in real time.
3 Fully redundant configuration provides no "single point of failure."
Inital testing of the units have shown that they're going to be very sweet indeed for our situation here. Specifically, they employ some interesting techniques for dealing with the "Sessions". They actually send a second cookie to the user to tie that user with the server that they are coming from. Cool stuff.
My only complaint regarding them at this point, is in setting them up. The web-based interface is nice, but it's not the most user-friendly piece of software. It would be nice to be able to do things like sort, search, etc. Also, it'd be nice if there was an API that would allow us to interact with the machine and it's data from some of our other programs (such as the PublishChanger). Minor details though, as it's not like this data is changing all that much. Basically, like Ronco says: "Just set it, and forget it!"
Time will tell, but I'm pumped about having this technology at our disposal. Projects from here on out will be developed keeping the load balancers in mind (not storing documents on the local server, not using sessions at all, etc).
Dusty Davidson
Lead Developer