Redirect wildcard subdomains to subdirectory, without changing URL in address bar

Question

I've read a lot of questions and answers about this on here but none that seem to solve my specific problem.

I want to redirect any subdomain to the subdirectory to match.

So: x.domain.com would go to domain.com/x, and y.domain.com would go to domain.com/y - But I want to do this without the URL in the address bar changing.

Here's what I have so far:

    Options +FollowSymLinks 

    RewriteEngine on

    RewriteBase /

    RewriteCond %{HTTP_HOST} !^(www)\. [NC]

    RewriteCond %{HTTP_HOST} ^(.*)\.domain\.com [NC]

    RewriteRule ^ /%1 [P,L]

But this takes me to a website redirect loop, with an incorrect address in the URL bar where the subdomain still exists.

For example, x.domain.com takes me to x.domain.com/x and I get a redirect loop error.

I'd be grateful if anyone can point me in the right direction! Nothing I change seems to work...

Answer 1

First of all, make sure that the vhost in the apache configuration is properly configured and all subdomains of domain.com are in the same host configuration (wildcard):

<VirtualHost *:80>
ServerName domain.com
ServerAlias *.domain.com
...

You can get the redirect working with the following htaccess configuration:

RewriteEngine on
RewriteCond %{HTTP_HOST} ^(.*)\.domain\.com
RewriteRule ^(.*)$ http://domain.com/%1/$1 [L,NC,QSA]

Now, if you open asd.domain.com it should redirect you to domain.com/asd. You will still have the problem, that the redirect is visible in the URL address bar. In order to prevent this, enable mod_proxy (and load the submodules) on your server and exchange the "L" flag with the "P" flag:

RewriteEngine on
RewriteCond %{HTTP_HOST} ^(.*)\.domain\.com
RewriteRule ^(.*)$ http://domain.com/%1/$1 [P,NC,QSA]

If this doesn't work, viewing the vhost configuration and the content of error.log on subdomain calling will be helpful!

References:
.htaccess rewrite subdomain to directory
http://httpd.apache.org/docs/2.2/mod/mod_proxy.html
http://httpd.apache.org/docs/2.2/rewrite/flags.html#flag_p

Answer 2

This can be achieved in .htaccess without mod_proxy provided your server is configured to allow wildcard subdomains. (I achieved that in JustHost by creating a subomain manually named *). Add this to your .htaccess file:

RewriteEngine On
RewriteCond %{HTTP_HOST} !^www\.website\.com$
RewriteCond %{HTTP_HOST} ^(\w+)\.website\.com$
RewriteCond %{REQUEST_URI}:%1 !^/([^/]+)/([^:]*):\1
RewriteRule ^(.*)$ /%1/$1 [QSA]