I have a Windows Server 2008 R2 Server (Server A) running as a domain controller with Active Directory, Group Policy, and DNS services.
I set up a second Windows Server 2008 R2 server (Server B), added it to the domain, and installed the Active Directory, Group Policy, and DNS Roles.
If I take Server A offline, then Active Directory and Group policy services are no longer available on Server B.
What would I need to do in order keep AD & GPO services operating while one server or the other is offline?
[edit]: Would I possibly need to do something involving dcpromo.exe on Server B? If so, what might that be?