Question

I have example.org and foo.example.org pointing to the same directory, /var/www/html/, and want foo.example.org to internally redirect to /var/www/foo/ using only mod_rewrite.

This is what I have so far, but no joy:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{HTTP_HOST} ^foo [NC]
    RewriteRule ^(.*)$ ../foo/$1 [L]
</IfModule>

This gets me 500s due to hitting the limit of 10 internal redirects, but I don’t understand why.

Answer 1

The reason for the internal redirect loop is that your only RewriteCond is the host name check. The host name won’t change after the internal redirect, and alas, will get triggered when the rules are parsed for the new request. You can solve this by adding a RewriteCond to check if the path already is set to the expected value (i.e. only rewrite requests with the path set to /var/www/html, and skip any other rewrite – as it has already been rewritten).

I’m going to suggest that it might be cleaner to do something like this through mod_vhost_alias, depending on your use case.