NEC Disk Array Controller N8103-89 - Manual (Page 92)

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2. RAID Levels
This section details the RAID levels which the disk array controller can support.
2-1. Characteristics of RAID Levels
The table below lists the characteristics of the RAID levels.
Level Function Redundancy Characteristics
RAID0 Striping No Data read/write at the highest rate
Largest capacity
Capacity: (capacity of single HDD) ×
(number of HDDs)
RAID1 Mirroring Yes Two HDDs required
Capacity: capacity of single HDD
RAID5 Striping of both data
and redundant data Yes Three or more HDDs required
Capacity: (capacity of single HDD) ×
((number of HDDs) - 1)
RAID10 Combination of striping
and mirroring Yes Four HDDs required
Capacity: (capacity of single HDD) × 2
2-2. RAID0
In RAID 0, data to be recorded is distributed to HDDs. The mode is called "striping."
In the figure below, data is recorded in stripe 1 (disk1), stripe 2 (disk 2), and stripe 3 (disk
3)… in the order. Because RAID0 allows all HDDs to be accessed collectively, it can
provide the best disk access performance.
Notice
RAID 0 cannot have data redundancy. If a HDD is defected, the data saved
in the HDD cannot be recovered.
Disk array controller
Disk 1 Disk 2
Stripe 1
Disk 3
Stripe 4
Stripe 2
Stripe 5
Stripe 3
Stripe 6