Boswell's Q&A

There's No Place Like Home

Admin wants main office to maintain role as primary Exchange server. Is he missing something in the migration?

• By Bill Boswell
• 02/08/2005

Last year we added a new branch onto our WAN and decided that we would serve up mail locally at the branch. Being that it was a new site we wanted to put in the latest technology, so we installed an Exchange 2003 server along with an Active Directory Connector. We continued to run Exchange 5.5 in the main office.

The time has now come to do the migration from Exchange 5.5 to Exchange 2003 in the main office, but we want the new server to be the "main" Exchange server, as it were. We want it to be the Internet connector and so forth.

I have been advised that, when installing the first Exchange server, it adopts certain roles similar to the way the first DC in an AD infrastructure has certain unique roles.

If I install the Exchange 2003 server in the home office, do I need to do anything to the branch office Exchange server to get it to give up these roles? Do we need to tear it down and build it again after we install the home office Exchange 2003 server?
— Simon

Simon: You won't need to tear down the Exchange 2003 server in the branch office. As far as mail delivery goes, the order you install Exchange 2003 servers doesn't matter.

When you use the Internet Mail Wizard to install the SMTP connector to the Internet after you install the Home Office Exchange 2003 server, you can either just remove the IMS from the Exchange 5.5 server or run them in parallel and use the costing to determine which one gets the traffic.

You're still in Mixed mode for Exchange, so that means that you have two sites and therefore two Administrative Groups. The Public Folder Hierarchy is rooted in the first Administrative Group with an Exchange 2003 server. You'll want to move it to the home office AG after you install the Exchange 2003 server there. Microsoft Knowledge Base Article 252105, "How to move a Top Level Hierarchy to a different Administrative Group," tells how to do this. It's very simple. Just a matter of creating a Public Folders folder then drag-and-dropping the Public Folder Hierarchy to the new folder in the home office AG.

You'll also need to make sure to include the new Exchange 2003 server in public folder replication. This is often where folks run into problems, so don't deinstall Exchange 5.5 from the legacy server until you verify that you can access all public folders (including Free/Busy) from Exchange 2003 machines. The simplest way to assign large numbers of public folders to additional servers for replication is the Pfmigrate.wsf script in the Exchange Deployment tools. Download it as part of the Exchange All Tools download from:

http://www.microsoft.com/downloads/details.aspx?FamilyID=e0f616c6-8fa4-4768-a3ed-cc09aef7b60a&displaylang=en

There are also a few Exchange services that rely on a specific server. You may want to point these services to the home office server.

1. Only one server is selected to generate the Offline Address Book (OAB). This is selected in the Properties window for the Default Offline Address List (or any custom AL you might have) in Exchange System Manager.

2. Only one server is selected to run each Recipient Update Service (RUS) query. This is configured in the Properties window of each Recipient Update Service icon (there is one for each domain and one for Enterprise.)
   

3. Only one server acts as Routing Group master to distribute changes to the Link State Table in each Routing Group. This is configured in the Routing Group folder in ESM. Right-click a member server in the Routing Group and select Set As Master in the flyout menu. Because each Administrative Group also represents a Routing Group in Mixed mode, and because you only have one Exchange server in each Routing Group, you won't need to make any adjustments here.

4. You will want to select the Exchange 2003 server to act as the Home Office bridgehead between routing groups. This is configured in the Properties window for the Routing Group connector.

5. Only one server acts as the Site Replication Service server for a site. This is selected in the Tools | Site Replication Services section of ESM. If you want to change SRS servers, you can start and stop the SRS using ESM but you have to be either at the console of the server running SRS or using remote desktop. Again, because you have only one Exchange 2003 server in a site, you'll be fine.

6. Only one server acts as the Exchange directory service endpoint for each Connection Agreement. This might be an Exchange 5.5 SP3+ server or it might be an Exchange 2000/2003 server running SRS. This is configured in the Properties window of the CA. You should make sure that the CA endpoints in the home office site point at the Exchange 2003 server. The branch office site does not have an Exchange 5.5 server (a Pure Titanium site) and therefore the Configuration connection agreement terminates at the SRS on that server. The Exchange 5.5 server acts as the Exchange endpoints in the Home Office site. You'll want to change the endpoints to the SRS on the new Exchange server in the home office right after you install the new server. Be sure to use TCP port 379 rather than port 389. SRS uses 379 to keep from interfering with LDAP in case it's running on a domain controller.

That's about it. If I missed something, I'm sure a reader will let me know and I'll include an update in a later column.