Fundamental changes to the migration strategy in Small Business Server 2008 have made the migration process more flexible and less disruptive to end users than in previous versions. While migration to SBS 2008 still requires detailed planning and testing, Microsoft provided a three-week window in which administrators can stage the migration, relieving the pressure to move all applications and user data in one shot.
SBS 2003 and SBS 2008 can now coexist in the same domain for up to 21 days, solely for purpose of easing the migration process. Once migration is complete, the source server is demoted, leaving only one SBS server in the domain per the standard licensing requirements. Because SBS client computers no longer need to be moved from old domain to new, the migration process can be completed during office hours without interruption to end users.
The Active Directory Migration Tool (ADMT) and Exchange Migration Wizard (used for migration to SBS 2003) are gone, and standard Active Directory (AD) and Exchange administration tools can be used to perform migration tasks once the new SBS 2008 server has been joined to the domain. Microsoft supports migration from Windows Server 2003 and SBS 2003, providing extra help for those migrating from SBS 2003 with a wizard that guides sysadmins through post-migration tasks.
SBS 2008 does not include Internet Security and Acceleration Server (ISA) in any form, so before migration you will need to change your network infrastructure to support an Internet router and configure SBS 2003 to use just one network interface.
The SBS 2008 installer will run in migration mode and check for service packs on the following components if they are installed on the source server: Exchange 2003 SP2, Windows Server 2003 SP2, SBS 2003 SP1 and Windows SharePoint Services 2.0 SP3.
Here is a pre-migration checklist:
The domain and forest functional levels must be raised before running the Source Server Migration Tool. To raise the domain functional level to 2003 on the source server, log on as administrator:
Repeat this procedure to raise the forest functional level, right clicking instead on Active Directory Domains and Trusts in the left pane and selecting Raise Forest Functional Level from the menu. Before proceeding, run the SBS 2003 Best Practices Analyzer, which can be downloaded here [http://go.microsoft.com/fwlink/?LinkId=113752], and correct any problems that the tool reports.
Now run the Source Server Migration Tool from the SBS 2008 disk on the source server:
The built-in administrator account is disabled by default in SBS 2008, so it’s best practice to create an account for migration purposes. Create a new user account on the source server called migration and make sure that it’s a member of the Domain Admins, Enterprise Admins and Schema Admins groups. Now you’re ready to create an answer file to install SBS 2008 in migration mode:
Follow the setup process for a usual installation of Windows Server, selecting the partition on which to install the operating system, etc. The server will restart twice, and if sbsanswerfile.xml is successfully detected after installation, setup will log on using the migration user specified in the file and continue with an automated setup of the SBS components, using the information provided.
Once setup is complete, you’ll be prompted to address any problems detected during installation (Figure 2).
What happens next depends on whether the source server is Windows Server 2003 or SBS 2003. The SBS Console’s Migration Wizard (Figure 3) is only supported if the source server is SBS 2003. The Migration Wizard serves as a guide for sysadmins of what to do and in what order.
While there is no need to migrate user accounts or groups, they do not appear in the SBS Console by default. To remedy this problem, follow the steps below to set the msSBSCreationState attribute on AD user and group objects:
Note that if you upgraded from SBS 2003, you should use the above procedure for groups only, and follow instructions in the Migration Wizard for migrating users. If the source server is Windows Server 2003, the SBS Console can be used to assign roles to migrated users.
Once your users and groups are in order, you should move Exchange mailboxes to the new server, which is an easy task with the Exchange Server 2007 Management Console:
Mailboxes can be moved to the new server during office hours, but be aware of the extra workload this will put on both source and destination servers. Users can continue working while their mailboxes are being moved; they will be prompted to restart Outlook once the operation is complete. No reconfiguration is required.
The final step is to decommission or repurpose the source server. You should uninstall Exchange and then demote the source server, using dcpromo.exe to change its status to a member server, rather than simply reformatting the disk.