Promise Technology FastTRAK66, Руководство пользователя

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Understanding Disk Array Concepts
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.
See Chapter 4 for a functional description.
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.
Spare Drive -- Under a RAID 1
setup, an extra “hot spare” drive can
be attached to the FastTrak66 and not
assigned to the array. In this case, it
will be put on standby. This drive will
be activated to replace a failed drive
that is part of the mirrored array. A
rebuild is performed automatically in
the background to mirror the good
drive onto 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.
Striping/Mirror (RAID 0+1)
6-4