Figure 1.3 Raid1+0 Concept; Figure 1.4 Raid5 Concept - Fujitsu Eternus DX60 User Manual

Chapter 1 Overview
1.2 Configuration
●
RAID1+0 (striping of pairs of disks for mirroring)
RAID1+0 combines the performance of RAID0 (striping) with the reliability of RAID1
(mirroring).
HDD0
Figure 1.3
●
RAID5 (striping with distributed parity)
Data divided into units of blocks and allocated across multiple disks together with parity
information created from the data. If one disk fails, the remaining data and parity blocks are
sufficient to allow the recovery of the lost data.
Figure 1.4
B
A
Mirroring
HDD1
A'
Mirroring
HDD4
RAID1+0 concept
Data writing request
A B
A B C
A B C
E F G
I J P
I, J, K, L
M P N
M, N, O, P
HDD0 HDD1 HDD2
RAID5 concept
ETERNUS DX60/DX80/DX90 Disk storage system User Guide
Copyright 2011 FUJITSU LIMITED
Data writing request
A B C D
C
C'
Mirroring
HDD2
B'
HDD6
HDD5
C D
D Create Parity Data
D P
A, B, C, D
P H
E, F, G, H
K L
O P
HDD3 HDD4
Parity for data A to D Parity A, B, C, D
Parity for data E to H Parity E, F, G, H
Parity for data I to L: Parity I, J, K, L
Parity for data M to P Parity M, N, O, P
28
D
D'
Mirroring
HDD3
HDD7
Striping (RAID0)
Mirroring (RAID1)
P3AM-3042-08ENZ0