One of the exciting new features in Windows Server 2003 is the Volume Shadow Copy (VSC) service. This service can be used to significantly reduce the amount of time that it takes to back up and restore Exchange Server 2003 databases. The VSC service works with backup applications and hardware to provide a shadow copy–based backup of your Exchange Server 2003 databases.
Essentially, the VSC will ask Exchange Server 2003 to pause—very quickly—to flush the memory structures to the databases, to pause new transactions, and to finish current transactions. Once this is accomplished, a (very) fast hardware copy of the databases is made to a neutral location on the server.
After the copy action is completed, the production databases are released for continued use while the shadow copy version is used for backup to tape. By default, after the backup of the shadow databases is completed, the shadow copy is deleted.
Future versions of this feature might include the scheduling of additional shadow copies periodically during the day, which you can then leave on disk when you require them for restore operations. This feature reduces the data that can be lost when you roll back to earlier database instances and can significantly increase the speed at which databases are recovered.