Figure 4.3 Raid1+0 Concept; Figure 4.4 Raid5 Concept - Fujitsu ETERNUS DX80 S2 Overview

Chapter 4 System Configuration
4.1 RAID Levels
●
RAID1+0 (striping of pairs of drives for mirroring)
RAID1+0 combines the performance of RAID0 (striping) with the reliability of RAID1 (mirroring).

Figure 4.3 RAID1+0 concept

A
HDD0
●
RAID5 (striping with distributed parity)
Data is divided into blocks and allocated across multiple drives together with parity information created
from the data in order to ensure the redundancy of the data.

Figure 4.4 RAID5 concept

A
A
E
I
M
HDD0
Data writing request
A
B
Mirroring
HDD1
A'
Mirroring
HDD4
Data writing request
A B C
B C
B C
F G
J P
I, J, K, L
P N
M, N, O, P
HDD1 HDD2
Parity for data A to D:
Parity for data E to H:
Parity for data I to L:
Parity for data M to P:
ETERNUS DX80 S2/DX90 S2 Disk storage system Overview
Copyright 2013 FUJITSU LIMITED
B C D
C
C'
Mirroring
HDD2
B'
HDD6
HDD5
D
Create parity data
D
D P
A, B, C, D
P H
E, F, G, H
K L
O P
HDD3 HDD4
P
A, B, C, D
P
E, F, G, H
P
I, J, K, L
P
M, N, O, P
34
D
D'
Mirroring
HDD3
HDD7
Striping (RAID0)
Mirroring (RAID1)
P3AM-4812-11ENZ0