It is important to back up your domain controllers to ensure their availability.
Backing up a server that acts as a domain controller is similar to backing up an Exchange 2000 member server. The primary difference between backing up a domain controller and backing up an Exchange 2000 member server is that your domain controller backups do not include Exchange 2000 databases (unless you are running Exchange 2000 on your domain controller). The method that you use to back up your domain controller depends on the disaster recovery strategy you select.
It is, therefore, important to understand the ascpects of domain controller availability.

This section contains the following information about backing up domain controllers:

• Backing up the System State of a domain controller
• Recommendations for backing up a domain controller

The information in this article applies to:

• Microsoft Exchange Server 2003 Enterprise Edition
• Microsoft Exchange Server 2003 Standard Edition
• Microsoft Windows Small Business Server 2003, Premium Edition
• Microsoft Windows Small Business Server 2003, Standard Edition
• Microsoft Exchange 2000 Server