IBM TotalStorage NAS Gateway 500, Administrator'S Manual, Page: 200 / 358

Restoring mirrors from a snapshot
You can restore the configuration information for all the remotely mirrored volumes,
if, for example, the software or the whole system, needs to be reinstalled.
CLI command
From the command line, enter geo_snapshot -a –f < snapshot_file >.
SMIT fastpath
The SMIT fastpath command to restore from a snapshot of the mirrors is smit
geo_snapshot .
WebSM
To restore from a snapshot of the mirrors from the main WebSM panel, navigate to:
NAS Management
→
NAS System
→
Remote Mirroring
→
Overview and Tasks
→
Apply
a snapshot of the remote mirroring devices to the system .
Managing snapshots
The NAS volume snapshot captures a consistent block-level image of a volume at
any given point in time. The snapshot remains the same even if the source volume
changes. The snapshot can then be used to create a backup of the volume. The
snapshot also provides the capability to access files or directories as they were at
the time of the snapshot. The snapshot can be generally viewed as a mechanism of
backing up a specific NAS volume.
Note: A snapshot needs approximately two to six percent of the space needed for
the volume that the snapshot was taken from. In the case of a highly active
snapped volume, this estimate could rise to 15 percent.
You can perform the following tasks when working with snapshots:
v
“Creating a snapshot”
v “Deleting a snapshot” on page 179
v
“Renaming a snapshot” on page 179
v “Rolling back a snapshot” on page 180
v
“Showing all current snapshots” on page 180
v “Configuring a snapshot schedule” on page 181
v
“Managing a snapshot schedule” on page 182
v “Showing a snapshot schedule” on page 182
v
“Snapshot Link Management” on page 183
Creating a snapshot
The snapvol -C command creates a snapshot. If you specified that snapshots
should be mirrored when you created the remotely mirrored NAS volumes, this
snapshot will also be remotely mirrored,
Use one of the following interfaces to create a snapshot.
Notes:
1. If you reach the maximum number of snapshots for a particular volume, more
snapshots can be added through the extendvol command (see “Extending the
size of a NAS volume” on page 169).
2. Within a cluster configuration, the cluster must be started to allow volumes to be
mounted. Unmounted volumes will not be in the list for creating snapshots.
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NAS Gateway 500 Administrator’s Guide