HP Veritas Volume Manager 5.0 -UX 11i v3 manual Administering volume snapshots

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Administering volume snapshots

Full-sized instant snapshots

volume are updated, its original contents are gradually relocated to the snapshot volume.

If desired, you can additionally select to perform either a background (non- blocking) or foreground (blocking) synchronization of the snapshot volume. This is useful if you intend to move the snapshot volume into a separate disk group for off-host processing, or you want to use the vxsnap dis or vxsnap split commands to turn the snapshot volume into an independent volume.

The vxsnap refresh command allows you to update the data in a snapshot each time that you make a backup.

The command, vxsnap reattach, can be used to attach snapshot plexes to the original volume, and to resynchronize the data in these plexes from the original volume. Alternatively, you can use the vxsnap restore command to restore the contents of the original volume from a snapshot that you took at an earlier point in time. You can also choose whether or not to keep the snapshot volume after restoration of the original volume is complete. See “Restoring the original volume from a snapshot” on page 317 for more information.

By default, the FastResync feature of VxVM is used to minimize the time needed to resynchronize the data in the snapshot mirror. If FastResync is not enabled, a full resynchronization of the data is required. For details, see “FastResync” on page 66.

See “Creating and managing full-sized instant snapshots” on page 327 for details of the procedures for creating and using this type of snapshot.

For information about how to prepare an empty volume for use by full-sized instant snapshots, see “Creating a volume for use as a full-sized instant or linked break-off snapshot” on page 323.