mod_append_hostname

modappendhostname is a very simple Apache 2.x filter module. It appends the hostname of the current machine, in an HTML comment, at the bottom of HTML content types:

Configuration:

LoadModule appendhostnamemodule modules/modappendhostname.so

AddOutputFilterByType append_hostname text/html

Very useful when one of your machines behind a load balancer is kinda broken. Based on the an example from Hacking Apache HTTP Server at Yahoo!. I actually wrote it an hour after the session, at ApacheCon US 2005, but I haven’t had a chance to post anything about it.