- Pre-Migration Operational Evaluations
- Exchange Migration Roadma
- Prerequisites and Precautions
- Active Directory Connector Operation
- Forest and Domain Preparation
- ADC Installation
- Connection Agreement Properties
- Initial Exchange 2003 Server Installation
- Connection Agreement Testing
- Site Replication Service Configuration
- Completing the Migration
- Shift to Exchange Native Mode
- Looking Forward
Completing the Migration
At this point, you've installed the ADC and your first Exchange 2003 server. You've replicated the public and system folders to the new server and verified that each of the Connection Agreements works.
You can now install additional Exchange 2003 servers in this and other sites and start laying out your new messaging infrastructure. This involves creating new Routing groups, moving mailboxes, moving connectors, decommissioning legacy servers, and shifting to Exchange Native mode.
Create Routing Groups
Each legacy site forms a separate Routing group in Exchange 2003, so as soon as you install an Exchange 2003 server in a second site, you should create a Routing Group connector between them and remove the legacy Site connector. This has several benefits.
You stop routing messages through the slow, cumbersome MTA on the legacy Exchange bridgeheads.
You reduce your reliance on the error-prone Gateway Address Routing Table (GWART) and move toward using the Link State Table exclusively for message routing.
Once you get multiple Exchange 2003 servers in each site, you can take advantage of fault tolerant message routing and reduce your reliance on a single bridgehead.
To replace the legacy Site connectors, just install a Routing Group connector between sites, select the Exchange 2003 as the bridgeheads, verify that messages flow between those two bridgeheads, and then remove the Site connectors using legacy Exchange Admin.
Do a final verification that mail sent from a user with a legacy Exchange home server in one site arrives in the mailbox of a user with a legacy Exchange mailbox in another site. This assures you that the legacy servers and the new servers all understand the new topology.
For safety's sake, once you have replaced sufficient Site connectors so that you don't need to worry about routing loops, you should start putting multiple routes between Routing groups to assure fault tolerance in case one network connection should go down.
For details on creating Routing Group connectors, and for details on SMTP routing and the operation of Link State tables, see Chapter 8.
Identify Legacy Exchange Services
It's important to map out the legacy services so you have a good idea how to transfer their functionality to Exchange 2003 as you migrate. Be on the lookout for servers hosting the following features:
Internet Mail Service (IMS). To retain access to Internet e-mail, make it a top priority to transfer your Internet mail from any legacy Exchange IMS servers to Exchange 2003 servers acting as bridgeheads for an SMTP connector. To assure continuity of service, leave the existing IMS connection in place with a high cost until you verify that the new SMTP connector works in all situations. See Chapter 8, "Message Routing," for details.
SNADS, PROFS, and ccMail connectors. Exchange 2003 does not support these connectors. Leave a legacy Exchange server in place to host the connectors while you find some other method to connect to these services or convince users to abandon them.
Third-party fax connectors. Verify that the vendor of the fax connector supplies an Exchange 2003 version and test it in your lab.
Routing Calculation Server. While you retain legacy Exchange servers in an organization, you need to provide them with routing information via the GWART. Only one legacy server in a site calculates the GWART. You can select the calculation server using the legacy Admin utility. Drill down to the Configuration container for the site and open the Properties window for the Site Addressing object. Figure 12.45 shows an example. Select an Exchange 2003 server from the dropdown list. Any Exchange 2003 server can perform this function. It does not need to run SRS.
Figure 12.45 You can use legacy Admin to select a different routing calculation server when the time comes to decommission the server.legacy Exchange serversmigration to Exchange 2003final stepsmigration from legacy Exchangefinal stepslegacy services. identifying
Before using an Exchange 2003 server to calculate the GWART, transfer all Internet mail routing to Exchange 2003 servers. When Exchange 2003 calculates the GWART, it removes the @ sign from the address scope. Legacy Exchange IMS requires this @ sign to work properly.
Bridgehead servers. Before decommissioning a legacy server that acts as a bridgehead for a Site connector or a Directory Service connector, evaluate whether you still need the connector. In most circumstances, once you have Exchange 2003 servers in all sites, you do not want legacy Exchange servers to act as bridgeheads.
Address Book Views. You cannot migrate legacy Address Book Views to Active Directory. Create custom address lists with LDAP queries that mimic the selection criteria used for a particular Address Book View.
Key Management Server (KMS). If you have deployed secure messaging in your legacy Exchange organization, you'll have at least one legacy Exchange server acting as the KMS. Exchange 2003 does not have a KMS function. That's because Windows Server 2003 Certification Authorities can store private keys, so you do not need a KMS. See the Microsoft white paper titled, "Key Archival and Management in Windows Server 2003" (download from http://snipurl.com/5z3s) for instructions on transferring the KMS database to a Windows Server 2003 CA.
Complete Mailbox Moves
During the initial testing of your first Exchange 2003 server, you moved a few user mailboxes from the legacy servers to the new server. Now that you have installed sufficient Exchange 2003 servers to handle your user population, continue moving mailboxes until all users have their mailboxes on new Exchange 2003 servers.
ESM can move four mailboxes at a time, so this portion of the migration should not take long unless you have users with extremely large mailboxes. See Chapter 7, "Managing Storage and Mailboxes," for details.