Backing up and restoring with snapshots

NDMP directory-level backup operations give you the ability to back up user-created snapshots of a NAS file system. Those snapshots are then stored as subdirectories. The snapshots can be taken at any time, and the backup to tape can be deferred to a more convenient time.

Procedure

For example, to back up a snapshot that is created for a NetApp file system, complete the following steps:

  1. On the console for the NAS device, issue the command to create the snapshot. SNAP CREATE is the command for a NetApp device.
    snap create vol2 february17
    This example creates a snapshot that is named FEBRUARY 17 of the /vol/vol2 file system. The physical location for the snapshot data is in the directory /vol/vol2/.snapshot/february17. The stored location for snapshot data depends on the NAS vendor implementation. For NetApp, the SNAP LIST command can be used to display all snapshots for a file system.
  2. Define a virtual file space mapping definition on the Tivoli® Storage Manager server for the snapshot data that is created in the previous step.
    define virtualfsmapping  nas1 /feb17snapshot  /vol/vol2  /.snapshot/february17 
    This example creates a virtual file space mapping definition named /feb17snapshot.
  3. Back up the virtual file space mapping.
    backup node nas1 /feb17snapshot mode=full toc=yes 
  4. After the backup is created, you can either restore the entire snapshot image or restore an individual file. Before you restore the data, you can create a virtual file space mapping name for the target directory. You can select any file system name as a target. The target location in this example is the directory /feb17snaprestore on the file system /vol/vol1.
    define virtualfsmapping  nas1 /feb17snaprestore  /vol/vol1  /feb17snaprestore
  5. Restore the snapshot backup image.
    restore node nas1 /feb17snapshot /feb17snaprestore
    This example restores a copy of the /vol/vol2 file system to the directory /vol/vol1/feb17snaprestore in the same state as when the snapshot was created in the first step.