The following are best practices from this chapter:
Use the in-place upgrade procedure for "quick and dirty" upgrades or when server equipment is newer .
Use the move mailbox procedure when deploying new server hardware or changing basic server architecture, or for risk-averse migrations.
Create a prototype lab to test the migration process and validate design assumptions.
Keep an Exchange 2000 Server in place to support legacy tools ”such as Conferencing Server, KMS, Chat, and Instant Messenger Server ”and other non-supported functionality if it is required in the migrated environment.
Leave legacy Exchange 2000 Servers in place for a few weeks following a move mailbox migration to ensure that all clients are redirected to their new mailbox locations.
Consider the use of advanced tools ”such as MIIS 2003, InterOrg/PF, and dedicated Exchange forests ”for complex situations involving multiple Exchange organizations.
When using the move mailbox approach, allow time between the deployment of the new servers and the migration to enable the new servers to "burn in." This is also an ideal time to migrate a pilot set of users.
Use the Exchange Deployment Tools to help minimize any issues associated with the migration process.
