What the dump engine backs up

The dump engine can back up a file, directory, qtree, or an entire volume to a tape.

In addition to backing up data in files, the dump engine can back up the following information about each file, as applicable:

• UNIX GID, owner UID, and file permissions
• UNIX access, creation, and modification time
• File type
• File size
• DOS name, DOS attributes, and creation time
• Access Control Lists (ACLs) with 1024 Access Control Entries (ACEs)
  Note: If you restore ACLs backed up from storage systems running Data ONTAP 8.2 to storage systems running Data ONTAP 8.1.x and earlier that have an ACE limit lower than 1024, a default ACL is restored.
• Qtree information
• LUN and LUN clones

  You can back up only an entire LUN object; you cannot back up a single file within the LUN object. Similarly, you can restore an entire LUN object but not a single file within the LUN.

  Note: The dump engine backs up LUN clones as independent LUNs.

When you back up data to tape, the dump command does not back up the LUN clones that are inconsistent. For all other LUN clones, the dump command locks their backing Snapshot copies to ensure that they do not become inconsistent during the backup.

When you back up a vault destination volume or a volume SnapMirror destination to tape, only the data on the volume is backed up. The associated metadata is not backed up. Therefore, when you try to restore the volume, only the data on that volume is restored. Information about the volume SnapMirror relationships is not available in the backup and therefore is not restored.

If you dump a file that has only Windows NT permissions and restore it to a UNIX-style qtree or volume, the file gets the default UNIX permissions for that qtree or volume.

If you dump a file that has only UNIX permissions and restore it to an NTFS-style qtree or volume, the file gets the default Windows permissions for that qtree or volume.

Other dumps and restores preserve permissions.