I have a scenario that I have windows 2003 Forest.
I have 3 Domain Controllers
1 DC is also Exchange server 2003
I have two forests have same above configurations
I simply want to upgrade my windows 2003 DCs to windows 2008 DCs in both forests and then create trust relationship for some applications i.e. ISA 2006 for both forests, SCOM monitoring for both forests etc ...
Both forests are on 10..x.x.x and in same building but are separately being administered.
My question is:
What precautions should I take to upgrade my windows 2003 DCs to Windows 2008 DCs while exchange server 2003 will not be upgraded to higher versions for the time being.