Media Recovery Using the Snapshot
The RESTORE command supports use of the 'WITH SNAPSHOT' option with virtual devices. An application issues the RESTORE DATABASE command, then interacts with the server through the VDI interface to provide the backup set meta data. After inspecting the meta data, the application receives a command to mount the snapshot. It makes the original content of the data files available on the system and responds when this is complete. The data files mounted must be byte-for-byte exactly the same as when the snapshot was taken with the BACKUP command.
Ideally, the file content is provided to the operating system (mounted) in response to the mount command. This provides the most functionality, highest availability, and easiest administration. However, some technologies or scenarios may not allow this, instead requiring a reboot of the operating system.
If the files cannot be mounted during the RESTORE command, the database should be detached or dropped from a running SQL Server prior to execution of the RESTORE command. This approach precludes restoration of individual files. Snapshot restore of individual files is only supported if the database exists.
See also