FAQs related to dump, NDMP, and WAFL

Following are some questions related to dump, NDMP, and WAFL in SnapLock.

Is it possible to use dump, restore, or NDMP to back up SnapLock volumes?

Yes, but there are some restrictions for restores. Dump and NDMP backups work exactly as they work on regular volumes. However, there are two restrictions with restore and NDMP restore:

True incremental restores are not supported on SnapLock volumes. The restore command automatically converts restore r to restore x if the destination volume is a SnapLock volume.
This restriction is necessary because of the way the incremental restore process works. For example, moving directories around and renaming them is not allowed on WORM volumes and causes the incremental restore to break.
Restore and NDMP do not get any free passes around the SnapLock protection and are bound by the same restrictions that apply to a regular client. This means that restore and NDMP cannot overwrite, modify, delete, or change attributes of any existing WORM files on a SnapLock volume.

Do dump, restore, and NDMP preserve the WORM attributes of the files?

Yes. The data streams of these features have been augmented to preserve the WORM attributes of files on a SnapLock volume when data is backed up, restored, or copied. However, for the WORM attributes to be meaningfully enforced, you must perform the restore to a SnapLock volume. If the backup from a SnapLock volume is restored to a non-SnapLock volume, the WORM attributes preserved are ignored, but they will not be enforced by Data ONTAP.