I use Mongrel and mongrel_cluster for all of my Rails apps so it was the obvious choice for our Rails based Knowledge Management system at Peritor.
Our app ran fine in WEBrick on the local development boxes but we had strange errors on the production Mongrels:
NoMethodError: undefined method `find’ for Cluster:Module
Locally it was also running fine with Mongrel. It took some time to find out that the mongrel_cluster gem_plugin that we use on the production boxes installs a global module named Cluster and that this module overshadowed our Rails model named Cluster. I already wrote the author about it and hopefully mongrel_cluster will use a separate namespace in the next release. Until then we manage the Mongrels ourselves. Maybe this will spare somebody a long debugging session…
