NOTE: Using <VirtualHost> parameter only.
How do I redirect a directory (say example.com/groups/) to a sub-domain (say groups.example.com), and also the www of that sub-domain (www.groups.example.com) to the non-www URL of that sub-domain (groups.example.com)?
Precisely (⇒ stands for 'should 301 redirect to'):
example.com/groups/ ⇒ groups.example.com
www.groups.example.com ⇒ groups.example.com
I have read that using <VirtualHost> is better than all those redirection rules that are usually used (i.e. that using redirection engine is pretty heavy on disk i/o). So, I would like to have the above problem solved using <VirtualHost> in .htaccess / httpd.conf if possible. Thanks!