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SmartStor NAS Product Manual
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7.3 Spare Drive
A spare is a disk drive that has been designated to replace a failed disk drive in a
RAID Volume. In the event of the failure of a disk drive within a RAID 1 or three
drive RAID 5 Volume, the spare drive is activated as a member of the RAID
Volume to replace a disk drive that has failed.
A spare drive cannot replace the failed drive in a RAID 0 Volume because of the
way in which data is written to the disk drives under RAID 0.
A spare drive is not available for a RAID 10 Volume because RAID 10 requires
all four disk drives in the SmartStor enclosure. However, when you replace the
failed disk drive, the SmartStor will automatically rebuild the RAID Volume using
the new disk drive.
You must designate a disk drive as a Spare. By default, and unassigned disk
drive is Free. Use WebPASM to designate the Free disk drive as a Spare. See
Maintaining a spare drive is a good precaution to protect your RAID Volume
integrity in the event of disk drive failure.
7.4 Automatic Rebuilding
When a disk drive in your RAID 1, 5, or 10 Volume fails, and a replacement disk
drive becomes available, the RAID Volume will rebuild itself to the new disk drive
automatically.
For RAID 1 and three-drive RAID 5 Volumes, you can designate a spare drive. If
a spare drive is present when the RAID Volume experiences a disk drive failure,
the rebuild will start automatically using the spare drive.
For RAID 1, RAID 5, and RAID 10 Volumes without a spare drive, the RAID
Volume will begin to rebuild itself automatically when you remove the failed disk
drive and install a new disk drive.
A RAID 0 Volume cannot be rebuilt because of the way in which data is written to
the disk drives under RAID 0. Even if there is a designated spare drive,
rebuilding is not possible for RAID 0 Volumes.
7.5 Partition and Format
When you create a RAID Volume on SmartStor, the RAID Volume is
automatically partitioned and formatted for you.
To use your RAID Volume, you must create Folders on the RAID Volume and
assign services to those Folders according to your requirements. SmartStor
provides file services for Windows, UNIX/Linux and Mac, so all of those PCs can
access the folders on the SmartStor, even though each PC might have a
different file system.