Does Apache Virtual Hosting work with localhost?

Question

I'm a newbie trying to learn how apache web server works. I've activated apache web server on my Mac PowerBook G4, and tweaked the config file to get PHP, SSI and CGI working.
If I type the url http://127.0.0.1/ I get the same page as http://localhost/
If localhost is the domain name for the address 127.0.0.1, can I assign other domain names to 127.0.0.1 using apache's virtual hosting?
Ti Powerbook G4   Mac OS X (10.4.4)  

Answer 1

localhost is defined as 127.0.0.1. You can use them interchangeably.
As for virtual hosts, sure. Apache doesn't care.
There are two ways of running virtual hosts.
Port-based virtual hosts use a port number other than the standard 80. They can be accessed via something like http://localhost:8000/
Name-based virtual hosts look at the hostname header in the request to work out which site to serve. You can run any number of sites on the same port number this way, but you need to be able to control DNS so that it points to your machine.
If you are just testing this locally you can edit /etc/hosts to add whatever hostnames you like;
127.0.0.1 localhost my.testsite.com me.mydomain.com
Now when you enter 'my.testsite.com' or 'my.mydomain.com' in your web browser, /etc/hosts will resolve this to 127.0.0.1 and you'll talk to your local apache server.
Note that the localhost entries don't have to be in your domain. You can use this to override any real hostname you like.
Of course, if you want remote users to access this site you'll need to setup something in the DNS, or edit their /etc/hosts files individually.