Cisco Cisco HDT Network Storage Hard Drive Trays 관리자 가이드
Configuring your Storage
Viewing the Snapshot Reserve Details
Linksys Small Business NSS4000 and NSS6000 Series Network Storage System Administration Guide
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Viewing the Snapshot Reserve Details
You can configure the NSS6000 series NAS to take snapshots of the data on an
existing volume. When you create a snapshot, a backup of each of the shares on
the volume is created and is available within the system’s file directory to which
end users of those shares have access. The advantage of a snapshot over a
backup is that a snapshot is user-accessible and can be used for quick file
recovery resulting from end-user error (such as an accidentally deleted file). A
backup is only accessible to the administrator through the NSS configuration
interface. Restoring data from a backup is generally a task that is scheduled with
the IT administration staff. Backups are usually used to restore the system from a
major system failure.
existing volume. When you create a snapshot, a backup of each of the shares on
the volume is created and is available within the system’s file directory to which
end users of those shares have access. The advantage of a snapshot over a
backup is that a snapshot is user-accessible and can be used for quick file
recovery resulting from end-user error (such as an accidentally deleted file). A
backup is only accessible to the administrator through the NSS configuration
interface. Restoring data from a backup is generally a task that is scheduled with
the IT administration staff. Backups are usually used to restore the system from a
major system failure.
Snapshots can be taken at various time intervals (such as hourly, daily, and so on).
Each time a snapshot is taken, the previous snapshot is overwritten. You can also
configure multiple snapshot sequences for the same volume. This is typically done
to have snapshots occur at different time intervals. For example, you might want to
capture a snapshot sequence for each hour, a separate sequence for weekly
snapshots, and one for bi-weekly snapshots. In this case, the volume has three
separate snapshot sequences. Each snapshot is overwritten when the next
snapshot of the same frequency is taken. To ensure data integrity, during the
creation of the snapshot (the duration is approximately a few seconds), no writes
can occur to the share.
Each time a snapshot is taken, the previous snapshot is overwritten. You can also
configure multiple snapshot sequences for the same volume. This is typically done
to have snapshots occur at different time intervals. For example, you might want to
capture a snapshot sequence for each hour, a separate sequence for weekly
snapshots, and one for bi-weekly snapshots. In this case, the volume has three
separate snapshot sequences. Each snapshot is overwritten when the next
snapshot of the same frequency is taken. To ensure data integrity, during the
creation of the snapshot (the duration is approximately a few seconds), no writes
can occur to the share.
The snapshot reserve is the amount of space that you want to allocate to the
snapshot on the associated array. Once set, this space is not available for other
storage use. The recommended amount of a reserve is generally between 10 to
20% of the total volume size. Note that if the period of time between snapshots is
greater, the amount of the reserve should be greater. Or, if there is a heavy amount
of activity on the volume, set a higher reserve. This is due to the snapshot reserve
being used to store the changes to the volume contents since the last time the
snapshot was taken.
snapshot on the associated array. Once set, this space is not available for other
storage use. The recommended amount of a reserve is generally between 10 to
20% of the total volume size. Note that if the period of time between snapshots is
greater, the amount of the reserve should be greater. Or, if there is a heavy amount
of activity on the volume, set a higher reserve. This is due to the snapshot reserve
being used to store the changes to the volume contents since the last time the
snapshot was taken.
NOTE
This feature is only available on the NSS6000. You cannot grow a volume if it is the
target of a snapshot. If you want to grow such a volume, delete the snapshots first
and then expand the volume.
target of a snapshot. If you want to grow such a volume, delete the snapshots first
and then expand the volume.