NEC Express5800 120Rj-2 User Manual page 87

User Guide
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 the order. Because RAID0 allows all HDDs to be accessed collectively, it
can provide the best disk access performance.
defective, the data saved in the HDD cannot be recovered.
RAID1
In the RAID1 level, data saved in a HDD is written to another HDD without change.
The mode is called "mirroring".
When data is written onto a single HDD, the same data is written onto another HDD. If
either of the HDDs is defective, the other HDD containing the same data can substitute
for the defective HDD. Thus the system can continue to operate without interruption.
RAID Controller
HDD 1
Stripe 1
Stripe 4
Figure 32: RAID0 Configuration
Note: RAID0 cannot have data redundancy. If a HDD is
RAID Controller
HDD 1
Stripe 1
Stripe 2
Figure 33: RAID1 Configuration
HDD 2 HDD 3
Stripe 2 Stripe 3
Stripe 5 Stripe 6
HDD 2
Stripe 1
Stripe 2
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