Microsoft® SQL Server™ 2000 supports snapshot backup and restore technologies in conjunction with independent hardware and software vendors. Snapshot backups minimize or eliminate the use of server resources to accomplish the backup. This is especially beneficial for moderate to very large databases in which availability is extremely important. The primary benefits of this technology are:
- A backup can be created in a very short time, typically measured in seconds, with little or no impact on the server.
- Restore can be accomplished from a disk backup just as quickly.
- Backup to tape can be accomplished by another host with no impact on the production system.
- A copy of a production database can be created instantly for reporting or testing.
Snapshot backups can be created for an entire database or individual files. They are functionally equivalent to conventional full database and file backups and can be rolled forward using conventional, differential and log backups. Like other backups, snapshot backups and restores are tracked in msdb.
The snapshot backup and restore functionality is accomplished in cooperation with third party hardware and/or software vendors. These vendors use features of SQL Server 2000 designed for this purpose. The underlying backup technology creates an instantaneous copy of the data being backed up. This is typically accomplished by splitting a mirrored set of disks or creating a copy of a disk block when it is written, preserving the original. At restore time, the original is made available immediately and synchronizing the underlying disks is done in the background, resulting in almost instantaneous restores.
For more information, see the SQL Server page at the Microsoft Web site. In addition, you can contact your enterprise storage and/or backup software vendor.