I was installing a Tomcat webapp that refused to work until I stumbled on someone else's issue with an unrelated product. The solution was to add the machine's name to /etc/hosts, to match the name returned by hostname. Is this required for general Linux networking to function correctly?
My webapp is running in a virtual machine so that I can test the webapp, and I don't normally bother with the /etc/hosts file on VMs. I just shook my fist and cursed Tomcat and webapp's behavior. I read http://serverfault.com/questions/118823, but that doesn't say if it's required or not.