I have a website with a primary domain name (call it domain1.com). Another domain name, domain2.com, is also pointed to that same site. So if you go to domain2.com it's the same website as domain1.com.

I want to do an internal rewrite so that anyone going to domain2.com goes to domain1.com/page instead (which also would be domain2.com/page).

I've been trying to do this using rewrite rules but I think perhaps I have the source wrong in the settings? It isn't working.

Help appreciated!