Have you ever wanted to push all the traffic from one host to another? If you’re using apache, it’s easy. I needed to have all traffic from a http://www.foo.com site go to https://secure.foo.com. Originally, I was thinking of having a meta header redirect on the index.html page, and creating a custom 404 page that would also do a redirect.
Luckily, some folks corrected me, and showed me an easier way. mod_alias (ver 2.0) can do this easily, and as far as I can tell, transparently. I just put this line in the virtual server section for www.foo.com:
Redirect permanent / https://secure.foo.com/
Now, every request for any file from www.foo.com gets routed to secure.foo.com. And since they share the same docroot, this is exactly what I wanted.
To do this, make sure you have mod_alias available. It should be either compiled in (you can tell with httpd -l) or a shared library (on unix, usually called mod_alias.so). You have to make sure to load the shared library; see LoadModule and AddModule for more information.