Understanding Interoperability and Migration in Exchange Server 2003


Topic Last Modified: 2006-03-07

A messaging migration is a type of deployment in which existing user mailboxes, public folders, and content are moved to another e-mail system. In the context of these topics, migration refers to the process of moving from a non-Exchange messaging system to Microsoft® Exchange Server 2003. This can involve replacing hardware, restructuring the underlying network topology, optimizing the Microsoft Active Directory® directory service, replacing messaging clients on workstations, and more.

Many of the planning, design, and deployment steps involved in a migration are the same steps that you take when deploying Exchange 2003 in an environment where there is no pre-existing messaging platform. For example, you must design server hardware, define an administrative and routing group topology for the organization, identify options for resource consolidation, and possibly deploy Microsoft Office Outlook®.

In addition to the planning, design, and deployment steps, when you migrate to Exchange 2003, you must ensure that users can continue to communicate with each other during and after the migration. This often requires deployment of connector components between the legacy system and the new Exchange 2003 organization, followed by directory synchronization, so that non-migrated and migrated users have complete address lists that contain all users in the company, no matter which system they actually reside on. Interoperability between the systems might not be necessary, however, if you can move all of your users to Exchange 2003 at once.

For more information about the tools, guidance, and additional resources for interoperability between Lotus Notes R5/R6, Exchange Server 2003, and Windows Server 2003 Active Directory that are available to download, see Resources for Moving to the Microsoft Collaboration Platform.

Migrating from a non-Exchange messaging system to Exchange 2003 typically entails:

  1. Planning and designing the future Exchange 2003 organization.

    For more information about planning, design, and deployment, see Planning an Exchange Server 2003 Messaging System (http://go.microsoft.com/fwlink/?LinkId=21766) and the Exchange Server 2003 Deployment Guide (http://go.microsoft.com/fwlink/?LinkId=21768).
  2. Assessing the existing messaging system to identify connectivity and migration opportunities and documenting its infrastructure.

  3. Developing an interoperability and migration strategy based on your assessment.

  4. Deploying the new Exchange 2003 organization, in whole or in part.

  5. Connecting Exchange 2003 to the legacy messaging infrastructure in a seamless way (that is, connecting the systems and synchronizing their directories).

  6. Deploying Outlook or Microsoft Office Outlook Web Access.

  7. Moving users and porting collaborative applications.

  8. Decommissioning the legacy system.

The topics in this section focus on migration-specific concepts. They present guidelines for documenting and assessing the messaging infrastructure, followed by a discussion of migration strategies. These topics then describe migration of user data in a single-phase scenario, as well as interoperability issues that you need to plan for in a multiphase migration. These topics briefly cover Outlook and Outlook Web Access deployment options. Also discussed are typical migration challenges, such as migration of existing workgroup applications, and how to address these challenges.

The topics in this section cover general strategies, as well as typical tasks that you must accomplish when you are migrating users and data to a new Exchange 2003 organization in a single phase or multiple phases. In the following sections, you can read about the actual steps that are required to connect Exchange 2003 to a non-Exchange messaging system, perform directory synchronization, synchronize calendar information, and move mailboxes using the Exchange Migration Wizard. It is recommended that you follow the explanations provided in the following topics in a computer lab (ideally, restore a backup with real data). This will help you to familiarize yourself with what needs to be done in a minimum amount of time.

After you perform a test migration successfully, you might want to revisit the topics in this section to adjust your project plans, then test again before approaching your production environment. Whether you are migrating from Novell GroupWise or another messaging system, careful project planning and thorough testing are key factors that can help you to complete your migration project successfully.