We have a cluster for WorldCupBlog and are running a pretty hacked up version of WordPress to make it all go. The past few days our traffic skyrocketed as we expected, but our servers were not able to handle the load, hence, we installed the WP-Cache plugin.
At first, we were seeing random errors that we could not duplicate…the errors were certain pages would come up 404 – page not found. The random part about it was that the page was a legit page, but was coming up not found. Reloading a few times and it would come up. Duplicating the error was difficult and not consistent.
Solution: Some of our servers were not set on the exact same time as our DB server. We set all of them to equal time, and the error went away. Yahoo. So if you are ever using this plugin on a cluster, make sure everything is synced. We probably should have had it like that, but as things progress, it is easy to forget details.