NEC N8100-1223F, Руководство пользователя

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Configuring Your Server 4-37
RAID Levels
This section details the RAID levels which the on-board RAID (MegaRAID ROMB) can support.
Characteristics of RAID Levels
The table below lists the characteristics of the RAID levels.
Level Function Redundanc
y 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)
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 (disk 1), 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.
IMPORTANT:
RAID 0 cannot have data redundancy. If a HDD is
defected, the data saved in the HDD cannot be recovered.
Disk array controller
HDD 1 HDD 2
Stripe 1
HDD 3
Stripe 4
Stripe 2
Stripe 5
Stripe 3
Stripe 6