How to setup Windows 2008 domain redundancy

[guest]

Basically, it is the same as windows 2003.

1. Install Windows 2008 and join the existing domain.
2. Promote it to a DC. Also check this how to.

How to add an additional DC in Windows 2008 forest
http://www.howtonetworking.com/server/w2008ad1.htm

3. Once Active Directory is installed then to make the new machine a global catalog server and DNS.

[guest]

For full redundancy, you may want to do DHCP 50/50 and DFS. These hwo to may help.

How to install DFS on Windows 2008
How to setup DHCP redundancy (50/50) on Windows 2008
http://www.howtonetworking.com/server/w2008.htm