Let me first try to explain our situation and maybe you guys can help me decide on the best path for the future. Mind you this infrastructure was setup WAY before my time here.
Our current environment consists of one domain, lets call it XYZ.com. In this domain we have 6 companies that are all part of XYZ.com. At our main building we have 2 DC's, both are 2003 R2. Each one of the other companies/locations have 1 DC that is part of XYZ.com and are all also 2003 R2.
We have started a new venture in another state and we are starting to plan for that location. This location will need to have a DC and need to be controlled by us here. This is a different company and thus, the domain is going to be different, let's say XYZXY.com. The new DC at this location will be a 2008 DC, and eventually we will hire IT support for that out of state location in which we would not them to have access to our infrastructure here, but we will need access to ours and theirs.
Now for the questions:
1. Because the new DC will be 2008, we are in the process of building a 2008 server for our XYZ.com domain as well. What implications could we face with a new DC on 2008 and the rest of our servers on 2003 R2. I know we must migrate AD to the new 2008 schema and such, what else am i missing in a mixed environment like this?
2. Since we are going to have a new domain at the new location, XYZXY.com, should a forest be created with 2 child domains? XYZ and XYZXY?
3. Are there other ways of doing this? Best practices?
Thank you for your time!