We currently have 3 x Domain controllers , 2 running Server 2008 R2 data center and on running Server 2008 R2 Enterprise, all have a Forest Level and a Domain Functional Level of 2003 server
I am now looking to raise both the Forest and Domain Functional Level to 2008 R2 for all DC'S
Can someone tell me if I need to , raise both on DC1 , then DC2 , then DC3 individually?
Do I raise the Forest level , then the Domain functional server on DC1, Then DC2 etc?
Do they all need a reboot as soon as they are raised?
We don't use Exchnage or Lync, so from what I have read it is relatively straight forward?
How long does it take per DC approx. to do raise the levels?