Compaq External RAID Controller & Subsystem Infortrend, Руководство по эксплуатации

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Infortrend
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logical drive. If a controller fails, the host I/Os originally assigned
to the failed controller will be taken over by the existing controller.
When the controller fails back (failed controller being replaced by a
new one), logical drives will be returned to the replacement
controller in its original configuration.
With logical volume - logical volumes can also be assigned to
different controllers. The only difference is logical volumes will be
used as base units when shifting control during controller failure.
A logical volume with logical drives of different
levels?
Multi-level RAID systems
1.
RAID (0+1)
- this is a standard feature of Infortrend RAID
controllers. It brings the benefits of RAID 1 (high availability)
and RAID 0 (enhanced I/O performance through striping).
Simply choose multiple drives (more than two) to compose a
RAID 1 logical drive, RAID (0+1) will be automatically
implemented.
2.
RAID (3+0)
- a logical volume is a multi-level RAID
implementation by its own rights. A logical volume is a logical
composition which stripes data across several logical drives (the
RAID 0 method). A logical volume with several RAID 3
members can be considered as a RAID (3+0), or RAID 53 as
defined in "The
RAID Book" (from The RAID Advisory Board).
3.
RAID (5+0)
- a logical volume with several RAID 5 members.