Areca ARC-5030 Series, Руководство пользователя

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INTRODUCTION
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with each disk being mirrored by exactly one other unique disk.
Therefore, all the characteristics for a traditional RAID 10 apply
to a RAID 1E when the latter has an even number of disks. Areca
RAID 10 offers a little more flexibility in choosing the number of
disks that can be used to constitute an array. The number can be
even or odd.
1.7.4 RAID 3
RAID 3 provides disk striping and complete data redundancy
though a dedicated parity drive. RAID 3 breaks up data into
smaller blocks, calculates parity by performing an exclusive-or
on the blocks, and then writes the blocks to all but one drive in
the array. The parity data created during the exclusive-or is then
written to the last drive in the array. If a single drive fails, data
is still available by computing the exclusive-or of the contents
corresponding strips of the surviving member disk. RAID 3 is best
for applications that require very fast data- transfer rates or long