Snapshot Properties - Overland Storage SnapServer Administrator's Manual

SnapServer 7.0 Administrator's Guide
Allocate about 10% of RAID set if
• Activity is write-light.
• Write access patterns are concentrated in
• A small number of Snapshots must be
There are two other processes that may affect the size of the snapshot space:
• Creating a Traditional RAID Volume – In the course of creating a new volume, a
drop-down list allows you to add a percentage of the capacity being allocated to the
new volume to the snapshot space. This feature defaults to 20 percent, the
recommended amount of space to reserve for snapshots. If you do not plan to use
snapshots with this volume, maximize volume capacity by reducing this percentage to
zero; if you do plan to use snapshots, adjust this percentage in accordance with the
guidelines discussed in the previous section,
Requirements.
• Creating a Traditional RAID Group – When two or more RAID sets are grouped
together, their snapshot spaces are added together. For example, if RAID set A with a
snapshot space of 50 GB is grouped with RAID set B with a snapshot space of 25 GB,
the resulting RAID set group will have a snapshot space of 75 GB. Depending on the
purpose you had in mind when grouping the RAID sets, the result of combining the
two snapshot spaces may or may not be desirable, and you will need to readjust the
size as described previously.

Snapshot Properties

From the Snapshot primary page table, you can click a snapshot name to access the
Snapshot Properties
or, for Traditional RAID configurations, roll back to a previous state.
Edit a Snapshot
You can edit the name and duration by changing the data in the detail fields.
Delete a Snapshot
Click the Delete Snapshot button and then click it again on the confirmation page. The
snapshot is deleted and all its associated data.
Rollback to a Previous State
NOTE: This is only available on a Traditional RAID configuration.
If you need to restore an entire filesystem to a previous state, you can do so without
resorting to tape. The snapshot rollback feature allows you to use any archived snapshot to
restore an entire filesystem to a previous state simply by selecting the snapshot and
clicking the Rollback button. During the rollback operation, data on the volume will be
inaccessible and changes blocked.
10400317-001 10/2011
a few places.
available at any point in time.
page. There you can edit the name and duration, delete the snapshot,
©2010-11 Overland Storage, Inc.
6 – Other Storage Options
Allocate about 25% of RAID set if
• Activity is write-heavy.
• Write access patterns are randomized
across the volume.
• A large number of Snapshots must be
available at any point in time.
Estimating Snapshot Space
6-7