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| Toll Free: +44 800 088 5522 Steps to Migrate Exchange 2003 to 2010 Cross Forest
Active Directory is an inevitable part of Exchange Server. It is a database that keeps a record of users, resources, and services in the form of objects. There are two types of objects in an AD: Contained Objects like tree, forest, OUs and Leaf Objects like printers, computers etc. A forest is an AD boundary and interaction between the forests and domains take place when a trust relationship between them is maintained. When a mailbox has to be moved, it can be in same/different domain, forest, or organization and depending upon all these factors, ways to migrate database are adopted.
Local Mailbox move from Exchange 2003 to 2010 is a task that can be performed using Exchange Management Console. However, if the mailboxes are to be moved from one forest to another, it definitely gives hard time to administrator. In this segment, we will have a brief idea as how to migrate Exchange 2003 to 2010 cross forest.
Step1) Set up a new Active Directory forest and install Exchange Server 2010 in the new forest and the forest may be in same or different organization.
Step2) The process of migrating mailboxes might not be a one night process. Therefore, ensure that a dial-tone database is created so that email send/receive process can be continued while the migration is executed. Also, take care of the fact that users can see the Global Address Book of each other and the free-busy info is synchronized.
Step3) For mail flow between Exchange 2003 and 2010, configure relay connectors for both the versions (SMTP Connector for Exchange 2003 and Send/Receive connector for Exchange 2010).
Step4) Now configure Frontend Identity Manager (FIM) for synchronizing the Global Address List (GAL) between Exchange 2003 and 2010. FIM is an identity management tool by Microsoft that helps to synchronize identities, manage certificates by integrating AD and Exchange Server.
Step5) To replicate the free/busy information between two organizations, configure the Inter Org Replication Tool available free by Microsoft.
Step6) For every contact in source forest, the GAL sync by FIM will create Mail Enabled Contacts at the destination forest. However, by using the custom code, there is provision to directly create Mail Enabled Users in destination forest.
Step7) Now when mail enabled users are created, use the Prepare-MoveRequest.ps1 script. Run this script on the target Server and it will copy all mailbox attributes of source forest to the target forest.
Step8) Now download the Active Directory Migration tool (ADMT) that will export Windows SID history and password of accounts from source to destination forests. The SID history contains the user information from source domain.
Step9) Now use the move mailbox cmdlet to export mailboxes from Exchange 2003 to Exchange 2010.
Migration at Small Level:
However, if the cross-forest migration has to execute at a small level, then instead of utilizing the Active Directory, it is better to export Exchange mailbox to PST. For few accounts, mailboxes can be migrated to Outlook PST and then the PST can be imported to desired Exchange account in any domain or forest as required.
