Storage Foundation for Windows (SFW) provides the capability to create a point-in-time image of all the volumes associated with a SQL Server instance. This image, called a snapshot set, is a complete copy of the SQL Server instance at the specific point in time the snapshots are taken.
SFW uses Veritas FlashSnap™ technology along with the Microsoft Volume Shadow Copy Service (VSS) framework to quiesce the database and ensure a persistent snapshot of the production data.
Quick Recovery is the term for creating and maintaining the SFW snapshot sets on-host for use in quickly recovering databases in the event of corruption or an accidental or malicious update. Quick Recovery is designed to augment your traditional backup methodology. The Quick Recovery solution provides fast recovery from logical errors and eliminates the time-consuming process of restoring data from tape. Databases can be recovered to the point in time when the snapshot was taken or, by using current logs, rolled forward to the point of failure.
Using the SFW Quick Recovery Configuration wizard, you can create multiple snapshot sets for each SQL Server instance and set up schedules for creating and refreshing the snapshot sets. The snapshot sets can be maintained on-host as a Quick Recovery solution.
If you are using Volume Replicator for replication, you can also synchronize snapshot sets on the secondary site. See the Volume Replicator Administrator's Guide.
SFW snapshots use a split-mirror snapshot method. The snapshot is a separate persistent volume that contains an exact duplicate of all the data on the original volume at the time the snapshot is taken. This type of persistent physical snapshot is also known as a Clone (HP) or a BCV (EMC). In contrast, copy-on-write snapshots, also known as metadata snapshots, only copy changed blocks to the snapshot and do not create a separate physical volume.
Because a snapshot set contains a split-mirror snapshot copy of each of the volumes in the database, the snapshot set requires the same amount of space as the original volumes.
Veritas FlashSnap technology is also integrated into the NTBackup 6.0 Advanced Client Option. This solution is preferred for on and off host snapshot-assisted backup.