How to select the logon DC

Hi all,

I have a client that has two physically separate buildings. They have a T1 connection between the two and have been running with 1 server for both buildings. Building 1 is on subnet 10.0.0.0 and bldg 2 is on 10.1.0.0.

I am setting up another DC in the 2nd building and was wondering how to configure the clients so that they logon/authorize by that DC2 rather than DC1. Do I need to set it up as a 2nd site, or can I set it as the same site.

thanks

Nate