Microsoft states thatfor Exchange 2007 http://technet.microsoft.com/en-us/library/1e80857c-b870-4a6d-a0f4-ff7b3a7be037.aspx The domain controller that is the schema master must have Microsoft Windows Server 2003 Service Pack 1 (SP1) installed. (By default, the schema master runs on the first Windows domain controller installed in a forest.) You must have at least one global catalog server in every Active Directory directory service site where you plan to install Exchange 2007. This global catalog server must be running Windows Server 2003 SP1. Windows Server 2003 SP1 is recommended for the following reasons: Windows Server 2003 SP1 supports Exchange 2007 service notifications. When a configuration change occurs in Active Directory, a notification is sent to the service. Several Exchange 2007 services use this notification. The notification mechanism in Windows Server 2003 SP1 is an improvement over the notification mechanism in Windows 2000 Server. Windows Server 2003 SP1 allows users to browse the address book in Microsoft Outlook Web Access. Windows Server 2003 SP1 provides the ability to look up distribution list membership in a more efficient manner than in Windows 2000 Server. Do the GCs only in sites that contain Exchange 2007 servers need to be 2003 SP1, or do all GCs in a domain need to be 2003 SP1? The article above seems to indicate only sites with ex2k7 servers but I'm looking for clarification. If the 2003 SP1 GC requirement only pertains to sites containing Exchange 2007 servers is there any impact with Outlook clients using non 2003 SP1 GCs for lookups?

Everything I have read and heard so far would indicate that the only relevent "requirement" is that there is a Windows Server 2003 SP1 server holding the Schema master role and in each site that has an Exchange Server 2007 mailbox server.Exchange Server 2007 uses the AD sites as the service discovery boundary as well as for mail routing but I have read that the Exchange server only prefers a Windows Server 2003 SP1 DC to communicate with indicating that it will fail over requests to another DC which has Windows Server 2003 SP1 in the event the ones in its own site are unavailable. Given the other points you mention on thereasons forWindows Server SP1, thedifferences used by Exchange Server 2007 are only server side callsand would not be required for any client GC lookups. It would be a good idea to have another Windows Server 2003 SP1 in the forest for redundancy and close to the AD site with Exchange sincea failure of allthe Windows Server 2003 SP1 DC's may bring Exchange functionality down. This would normally be acheived with normal AD site design best practices. The Microsoft document "Deploying a Complex Exchange Server 2007 Organization" http://www.microsoft.com/downloads/details.aspx?familyid=32BA768D-9727-464A-B7E2-3E037D61A8D6&displaylang=enand http://technet.microsoft.com/en-us/library/aa998561.aspxgivemore information on this. Cheers, Rhys

Old post I realise but possibly the best place for my query. I understand the requirement to have a GC in each site where Exchange 2007 servers exist. Would I be right in presuming the Exchange servers should be able to use GC's in other AD sites or is it limited only to the GC in it's AD site ? Currently all Exchange 2007 servers are in one AD site (in UK) with a GC, although there are several AD sites in the UK with GC's. The AD design has sites typically related to physical country location. If the GC in the Exchange server AD site is rebooted it causes Exchange lookup issues. App log on a HT is finding the other GC's Event 2080's with CDG 177101171 which looks OKCheers, CH

Exchange servers will use a DC in another site if there are no usable DCs in its own site. But it won't use any intelligence in choosing that DC, i.e., it would just as likely choose a DC in Singapore as it would one across town. Be patient, the failover could take something like 15 minutes. -- Ed Crowley MVP "There are seldom good technological solutions to behavioral problems." . "Calvin or Hobbes" wrote in message news:4b1805bd-f87f-4ed9-b7c8-42d247edca7e... Old post I realise but possibly the best place for my query. I understand the requirement to have a GC in each site where Exchange 2007 servers exist. Would I be right in presuming the Exchange servers should be able to use GC's in other AD sites or is it limited only to the GC in it's AD site ? Currently all Exchange 2007 servers are in one AD site (in UK) with a GC, although there are several AD sites in the UK with GC's. The AD design has sites typically related to physical country location. If the GC in the Exchange server AD site is rebooted it causes Exchange lookup issues. App log on a HT is finding the other GC's Event 2080's with CDG 177101171 which looks OK Cheers, CHEd Crowley MVP "There are seldom good technological solutions to behavioral problems."

Ed, I believe the problem was immediately the DC was rebooted E2K7 users could not do email lookups to send new emails in Outlook. Is that what you mean by failover - do you mean Exchange "failover" to another DC ? The other DC's are in another AD site, but geographically local to the Exchange AD site - in the same data centre.. Cheers, CH >Exchange servers will use a DC in another site if there are no usable DCs in its own site. But it won't use any intelligence in choosing that >DC, i.e., it would just as likely choose a DC in Singapore as it would one across town. Be patient, the failover could take something like 15 >minutes. >-- >Ed Crowley MVP >"There are seldom good technological solutions to behavioral problems."Cheers, CH

You should have DC redundancy within the site Exchange is in. If you don't have that, you might consider collapsing the sites into one, especially if there's no reason to have them separate. By failover, I mean Exchange will start using another DC. But, like I said, it'll be a little while, like 15 minutes, before it switches. -- Ed Crowley MVP "There are seldom good technological solutions to behavioral problems." . "Calvin or Hobbes" wrote in message news:5706eff9-85ee-40e6-957a-9f77a53467c0... Ed, I believe the problem was immediately the DC was rebooted E2K7 users could not do email lookups to send new emails in Outlook. Is that what you mean by failover - do you mean Exchange "failover" to another DC ? The other DC's are in another AD site, but geographically local to the Exchange AD site - in the same data centre.. Cheers, CH >Exchange servers will use a DC in another site if there are no usable DCs in its own site. But it won't use any intelligence in choosing that >DC, i.e., it would just as likely choose a DC in Singapore as it would one across town. Be patient, the failover could take something like 15 >minutes. >-- >Ed Crowley MVP >"There are seldom good technological solutions to behavioral problems." Cheers, CHEd Crowley MVP "There are seldom good technological solutions to behavioral problems."

Ed, >You should have DC redundancy within the site Exchange is in. If you don't have that, you might consider collapsing the sites into one, >especially if there's no reason to have them separate. Ahh OK. From what I have read the requirement to have a seperate AD site for Exchange is no longer nexessary with Exchange 2007 onwards ? I believe the reason it exists is that it was an Exchange 2003 recommendation - do you agree ? If so it makes sence IMHO to collapse the AD site. Is that an easy process ? Do I just move the servers to another existing site and or change the associated subnet then delete the current Exchange AD site ? >By failover, I mean Exchange will start using another DC. But, like I said, it'll be a little while, like 15 minutes, before it switches. Well 15 mins is a no go really so I guess either add another GC to the Exchange site or collapse depending on your thoughts to the above.. Cheers, CH

http://msexchangeteam.com/archive/2007/03/28/437313.aspx http://technet.microsoft.com/en-us/library/cc780655(WS.10).aspx Hope you find it helpful. Regards, Pushkal MishrA

I don't recall it ever being necessary to have a separate AD site for Exchange. All you should have to do is change the subnet & site definitions in AD. Exchange should figure things out. If you're worried about it, you could shut down the Exchange servers, make the changes, wait for replication, then start the Exchange servers, but I don't know that it is necessary to do that. -- Ed Crowley MVP "There are seldom good technological solutions to behavioral problems." . "Calvin or Hobbes" wrote in message news:11273f07-f8f2-47a2-8662-7770747dc42a... Ed, >You should have DC redundancy within the site Exchange is in. If you don't have that, you might consider collapsing the sites into one, >especially if there's no reason to have them separate. Ahh OK. From what I have read the requirement to have a seperate AD site for Exchange is no longer nexessary with Exchange 2007 onwards ? I believe the reason it exists is that it was an Exchange 2003 recommendation - do you agree ? If so it makes sence IMHO to collapse the AD site. Is that an easy process ? Do I just move the servers to another existing site and or change the associated subnet then delete the current Exchange AD site ? >By failover, I mean Exchange will start using another DC. But, like I said, it'll be a little while, like 15 minutes, before it switches. Well 15 mins is a no go really so I guess either add another GC to the Exchange site or collapse depending on your thoughts to the above.. Cheers, CHEd Crowley MVP "There are seldom good technological solutions to behavioral problems."

Ed, Thanks for all the advice. >I don't recall it ever being necessary to have a separate AD site for Exchange. >All you should have to do is change the subnet & site definitions in AD. Exchange should figure things out. If you're worried about it, you could shut down the >Exchange servers, make the changes, wait for replication, then start the Exchange servers, but I don't know that it is necessary to do that. Cheers, CH