Raid Levels - NEC NovaScale R480 E1 User Manual

RAID Levels

Characteristics of the RAID Levels
The table below lists the characteristics of the RAID levels.
Level Function
RAID0 Striping
RAID1 Mirroring
Striping of both data
RAID5
and redundant data
RAID6 Striping of both data
and redundant data
RAID10 Spanning of RAID1
RAID50 Spanning of RAID5
RAID0
In RAID0, data to be recorded is distributed to HDDs. The mode is called "striping".
In the figure below, data is recorded in stripe 1 (disk 1), stripe 2 (disk 2), and stripe 3 (disk 3)... in this order. Because
RAID0 allows all the HDDs to be accessed in parallel, it provides the best disk access performance.
IMPORTANT:
saved in the HDD cannot be recovered.
Redundancy
No
Yes
Yes
Yes
Yes
Yes
RAID0 does not have data redundancy. If a HDD is defective, the data
RAID Controller
HDD 1
Stripe 1 Stripe 2
Stripe 4 Stripe 5
Characteristics
•
Data read/write at the highest rate
•
Largest capacity
•
Capacity: (capacity of single HDD) ×
(number of HDDs)
•
Two HDDs required
•
Capacity: capacity of single HDD
•
Three or more HDDs required
•
Capacity: (capacity of single HDD) ×
((number of HDDs) - 1)
•
Three or more HDDs required
•
Capacity: (capacity of single HDD) ×
((number of HDDs) - 2)
•
Four or more HDDs required
•
Capacity: (capacity of single HDD) ×
((number of HDDs) - 2)
•
Six or more HDDs required
•
Capacity: (capacity of single HDD) ×
((number of HDDs) - 2)
HDD 2 HDD 3
Stripe 3
Stripe 6
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