I have a client who has an IP based site using [domain1.com]

I have setup a subdomain [sub.domain1.com] which my client wishes to point a second domain [domain2.com] to the subdomain [sub.domain1.com].

Is this possible in Ensim or should it be done differently rather than using a subdomain?

Any help would be greatly appreciated. :)

I think this problem can be solved by apache mod_rewrite mechanism.

I'm sorry, I'm not that familiar with apache mod_rewrite, would you have any instructions to follow?

Anyone else got some pointers about how to do this?

EDIT > Can this be done with DNS?

you have to point the domain2 to the same ip where sub.somain1 is pointed; after that it's all a matter of configuring httpd.conf correctly.

You can either use mod_rewrite or (simpler and faster) just add SiteAlias for the sub.domain1's VirtualHost (this way, users coming to domain2.com would get contents of sub.domain1.com but they will see domain2.com in the URL). Also, you can create a Redirect that would change the URL string from domain2 to sub.domain1 if that's what your client needs.

In general, read Apache core docs on Redirects and SiteAlias.

Thanks piramida, I'll give it a shot.