Trying to set up Apache2 as a proxy for mongrel on my new Ruby on Rails server, following the instructions on the mongrel site. I kept getting “403 Forbidden” errors on every request. I found a comment that seemed to describe the same situation. Sure enough, editing /etc/apache2/mods-enabled/proxy.conf to change “Deny” to “Allow” fixed the problem. I kept ProxyRequests turned off, which is supposed to prevent my site from becoming an open proxy, but I’m still nervous about removing that “Deny” directive. I wish there were a more authoritative source of information on this.