using mod_rewrite to redirect from subdomain to maindomain - mod-rewrite

Question

My problem is that i have a functioning subdomain (sub.mydomain.com). sub is loaded in mydomain.com/sub.
What i would like to do is to redirect all requests to sub.mydomain.com to mydomain.com.
Somehow it seems that when im the subdomain i cannot access the rootfolder (main domain). I can get it working with from mydomain.com/sub to mydomain.com. But not from the subdomain.
Currently im using:
RewriteEngine on
RewriteRule ^(.*)/?$ /home/web/webuser/$1 [L]
When accessing sub.mydomain.com i get a 500 Internal Server Error.
Is there a restriction in accessing the main from a sub? (rights wise)
Or maybe another way of getting to main, perhaps something like (../$1)
Thanks
EDIT:
I only have access to .htaccess. So DocumentRoot cannot AFAIK be used in .htaccess file.
What about symlinks? I dont really know what it does, but i assume that it links two locations? The only code i found for that enables symlinks (Options +FollowSymlinks) - but this line doesnt say anything about what to link (perhaps im all wrong)
Btw. thanks for input so far !

Answer 1

I must admit that I did not fully understand your question. Do you want to redirect everything from sub.mydomain.com/whatever to mydomain.com/whatever? In that case, the following (put in the config file of your sub.mydomain.com) might work:
RewriteEngine On
RewriteRule ^/(.*)$ http://mydomain.com/$1 [R,L]
It redirects on the client side, meaning that the user will see mydomain.com/sub in the browser.
EDIT: I think I understand your question now. Yes, it's a permissions issue: If the DocumentRoot of your web site is /whatever/sub, then you cannot just access /whatever by adding "/.." to the URL. I hope you understand that this is a good thing. :-) mod_rewrite just changes the URL, so it cannot do that either.
So, to solve your problem, you need to either change the DocumentRoot of sub.mydomain.com or create a symlink that allows you to access the required directory (e.g. /whatever/sub/redir-target -> /whatever). Be careful with the symlink option, though, since it will create valid directories of infinite length on your file system (/whatever/sub/redir-target/sub/redir-target/...) and some scripts cannot cope with that.
EDIT2: Instead of a symlink, you might want to create an alias, e.g., something like this:
Alias /redir-target /home/web/webuser
RewriteEngine On
RewriteCond %{REQUEST_URI} !^/redir-target/.*$
RewriteRule ^/(.*)$ /redir-target/$1
Still, I think the easiest solution is to change the DocumentRoot...

Answer 2

Why not try using a Redirect Directive from mod_alias?

Answer 3

It's difficult to provide a definitive answer without knowing more about your server configuration.
The following might work and is at the very least a decent starting point:
RewriteEngine On
RewriteCond %{HTTP_HOST} ^sub\.mydomain\.com
RewriteRule (.*) /$1 [L]
Ideally that would go in your httpd.conf, but might work from a .htaccess file (again, more information about how your subdomains are setup would be helpful).