About data restoration

When to restore data from tape

You restore data from tape under the following circumstances:

Files were deleted from disk but backed up to tape.
For example, if you inadvertently delete a file and want to restore the file, you can recover the file from tape.
Files are corrupted. If some files are corrupted, you can restore the subtree containing the files.
No disk slots are available for expansion. If the storage system runs out of storage space, you can do the following tasks:
- Back up the entire storage system.
- Replace the current disks with disks of greater capacity.
- Set up volumes on new disks.
- Restore the storage system from tapes.
The entire storage system is damaged and unusable. Call Network Appliance Technical Support to determine whether you can repair the storage system and restore data from tape.

When not to restore data from tape

You do not need to restore a deleted file from tape if you can recover the deleted file from a Snapshot copy on the storage system. If the file is in a Snapshot copy, copying the file to the active file system is faster than recovering the file from tape.

Note
If you attempt an incremental restore to a storage system running Data ONTAP 6.2 or later from a storage system running a version earlier than 6.2, the restore will fail because of a formatting code change between the two code releases. You need to run the full backup again after you have upgraded to 6.2.