the user is automatically redirected to the appropriate domain
What do you understand by this???
The host access is by IP address.
A domain name is simply a convenient designation for a person not to remember the numbers of the IP address.
Computer always accesses the host with the specified address.
Domain .by is key, but if the user is in Russia to extradite him .EN ?
Output in the browser bar the name?
Well define the region of the user on a proxy and substitute, and fast.