Unfortunately, WordPress didn’t get along with this solution especially well. The WordPress engine didn’t like being accessed through the test subdomain, as it expected a single host name to be designated as its home location. Even though I could open the blog at the test address, all the dynamically generated links to scripts, style sheets, archives and such still pointed to the live version. I also couldn’t log in to the administrative interface at the test version, as it kept redirecting me to the live login page.

I knew PHP stored the actual host name that was used to access the page in the $_SERVER['SERVER_NAME'] variable, and I thought a simple solution would be to make WordPress use that instead of the basic URL set in the configuration. I had very little experience with WordPress internals, so it took me some time to figure out how to implement this, but I eventually succeeded. I wrapped the code into a plugin so that the functionality can be easily enabled or disabled and doesn’t affect the base WordPress code.

So, behold! My first WordPress plugin ever:

<?php /* Plugin Name:    Server Name Support Description:    Allows the blog to be accessed with multiple server names Author:         Michal Wojciechowski Version:        0.0.1 Author URI:     http://odyniec.net/ */ $sns_home = preg_replace('!://[a-z0-9.-]*!', '://' . $_SERVER['SERVER_NAME'], get_option('home')); function sns_home() { global $sns_home; return $sns_home; } function sns_replace_host($url, $path = '') { return preg_replace('!://[a-z0-9.-]*!', '://' . $_SERVER['SERVER_NAME'], $url); } add_filter('pre_option_home', 'sns_home'); add_filter('pre_option_siteurl', 'sns_home'); add_filter('pre_option_url', 'sns_home'); add_filter('stylesheet_uri', 'sns_replace_host'); add_filter('admin_url', 'sns_replace_host'); ?>

In case you’d like to use it (not very likely, as I don’t think my use case is that common), all you need to do is save the above code in a .php file, place it in the wp-content/plugins directory, and activate it in the WordPress admin interface.