AMCC 3ware 9000 Series, Руководство пользователя

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Glossary
182 3ware 9000 Series Serial ATA RAID Controller User Guide
preserved on the paired drive. Mirrored disk arrays include RAID 1 and
RAID 10.
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Non-redundant units. A disk array without fault tolerance (RAID 0,
single disk, or JBOD.).
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OCE (Online Capacity Expansion). The process of increasing the size of
an existing RAID unit without having to create a new array.
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Parity. Information that the controller calculates using an exclusive OR
(XOR) algorithm and writes to the disk drives in RAID 5 and RAID 50
units. This data can be used with the remaining user data to recover the
lost data if a disk drive fails.
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PCB . Printed circuit board.
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P-Chip.
PCI interface chip that connects the PCI bus to the high-speed
internal bus and routes all data between the two using a packet switched
fabric. There is one P-chip per controller card.
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Port ID . A unique identifier for a specific port in a system. Also called a
drive ID.
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Rebuild task schedule . The specification for when rebuilding, may
occur, including start time and duration.
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Rebuild a unit . To generate data on a new drive after it is put into service
to replace a degraded drive in a fault tolerant unit (for example, RAID 1,
10, 5, or 50).
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Redundancy.
Duplication of data on another drive or drives, so that it is
protected in the event of a drive failure.
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Remove a drive.
The process of making a drive unavailable to the
controller.
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Remove a unit.
The process of making a unit unavailable to the
controller and the operating system. After a unit is removed it can be hot
swapped out of the system.This is sometimes referred to as exporting a
unit.
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RLM (RAID Level Migration).
The process of using an existing unit of
one or more drives and converting it to a new RAID type without having
to delete the original unit. For example, converting a single disk to a
mirrored disk or converting a RAID 0 unit to a RAID 5 unit.
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Self-test.
A unit test that can be performed on a scheduled basis. in 3DM,
available self-tests include Upgrade UDMA mode and Check SMART
Thresholds.
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Stagger time. The delay between drive groups that will spin up, at one
time, on a particular controller.
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Stripe size . The size of the data written to each disk drive in RAID unit
levels that support striping. The size of stripes can be set for a given unit