I have to upgrade two W2K8 DCs, one of which seems to have pretty much all clients authenticating to it. There will be two other DCs in the site when I do this.

What is the likely effect? Will Exchange 2010 freak out if it happens to be bound to this server? I don't especially want to take it out of the domain just to do this RAM upgrade.

Hello,

1. Make sure when you do RAM upgrade you do it out of business hours.  

2. Take a proper backup of DC before doing such activity.

3. transfer the required roles from that server to near by server or another server in same site.

4. for exchange server make sure your outlook authentication or LDAP Query should go to another DC in near by site or  another DC in same site.

Hello,

there is no problem taking down the DC for RAM upgrade

Assure that at least one other DNS Server and DC with GC enabled for the domain is reachable and clients are configured to use that DNS Server on the NIC.

Also assure in the Exchange management console that another DC is listed so Exchange can work correct.

There is no need to transfer FSMO roles to another DC for short time shutdown. Authentication doesn't require FSMO roles.
also if you transfer the PDCEmulator FSMO to another DC you have to reconfigure the time service.

Hi,

I agree with Meinolf Weber

Thanks this worked fine. The only issue I had was that messages sent during the downtime did not leave the Outbox in Outlook 2010. That is, the message was sent but a copy remained in the Outbox.

I have to do this now on a server that contains DHCP: two scopes, one is data and one is for VOIP. I am hoping that only those leases that expire during the downtime will have problems.