Compaq N2400 - TaskSmart - 1 GB RAM Administration Manual page 49

2-20 Compaq TaskSmart N2400 Administration Guide
Snapshots, Restoring Files, and Directories
Snapshots may be used as a highly efficient way to maintain online backups of
a virtual disk, enabling immediate file and directory recovery. Snapshots are
assigned to a drive letter and used exactly like virtual disks. If a file or
directory is lost or corrupted, it can be recovered easily. The user can switch to
the snapshot drive and copy the file or directory back to its original location on
the virtual disk or an alternate location.
IMPORTANT: To preserve the integrity of a point-in-time snapshot of your virtual disk,
ensure that it is exported as read-only.
Snapshots and Restoring a Virtual Disk
When data on a virtual disk becomes corrupted, restore the virtual disk from
your normal tape backup. Alternatively, use an existing and valid snapshot of
the virtual disk to restore the entire virtual disk from the existing snapshot.
NOTE: Snapshots are not a replacement for normal tape backup.
CAUTION: Snapshot recovery causes temporary pool space consumption
because of the need to preallocate pool space for the newly recovered virtual
disk. There must be sufficient free pool space; otherwise, a pool-full condition
may occur and Lifeguard may delete the snapshot from which you are restoring.
If your only snapshot is deleted, you must restore from tape backup. See "SWVR
Lifeguard Service" later in this chapter.
The Restore From Snapshot Wizard schedules the re-creation of a virtual disk
from a snapshot. If specified, upon successful completion of the schedule, the
previous virtual disk and snapshot are both deleted. Perform the following
steps:
1. Remove all shares associated with the virtual disk that you are intending
to restore.
2. Delete all snapshots of the virtual disk that you are intending to recover,
except for the snapshot that will be used for the recovery. Additionally,
to free up pool space, delete any unnecessary snapshots of other virtual
disks in the same pool.