Supero SUPER 370DDE, Руководство пользователя

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Chapter 5: The FastTrak 100 RIAD Card (370DDE)
Mirroring (RAID 1)
Writes duplicate data on to a pair of drives while reads are performed in
parallel. ATA RAID 1 is fault tolerant because each drive of a mirrored
pair is installed on separate IDE channels. If one of the mirrored drives
suffers a mechanical failure (e.g. spindle failure) or does not respond,
the remaining drive will continue to function. This is called
Fault
Tolerance
. If one drive has a physical sector error, the mirrored drive
will continue to function.
On the next reboot, the FastBuild TM utility will display an error in the
array and recommend to replace the failed drive. Users may choose to
continue using their PC, however Promise recommends replacing the
failed drive as soon as possible.
Due to redundancy, the drive capacity of the array is half the total drive
capacity. For example, two 1GB drives that have a combined capacity
of 2GB would have 1GB of usable storage. With drives of different
capacities, there may be unused capacity on the larger drive.
Using a Spare Drive
Under a RAID 1 setup, an extra “hot spare” drive (a third drive on
FastTrak100) can be attached to the FastTrak100 and not assigned to
the array. Such a drive will be activated to replace a failed drive that is
part of a mirrored array. A rebuild is performed automatically in the
background to mirror the good drive data on to the spare.
At a later time, the system can be powered off and the failed drive can
be physically removed and replaced. Spare drives must be the same or
larger capacity than the smallest array member.