●
RAID6 (Striping with Double Distributed Parity)
Allocating two different parities on different drives (double parity) makes it possible to recover from up to two
drive failures.
Figure 6 RAID6 Concept
P2
M, N, O, P
P2
I, J, K, L
A
E
I
M
A
B
C
D
Data writing request
B
F
J
P1
M, N, O, P
C
G
P1
I, J, K, L
D
P1
E, F, G, H
P2
E, F, G, H
N
K
O
P1
A, B, C, D
H
L
P
P2
A, B, C, D
A
B
D
C
Create parity data
Drive#0
Drive#1
Drive#2
Drive#3
Drive#4
Drive#5
Parity for data A to D: P1
A, B, C, D
and P2
A, B, C, D
Parity for data E to H: P1
E, F, G, H
and P2
E, F, G, H
Parity for data I to L: P1
I, J, K, L
and P2
I, J, K, L
Parity for data M to P: P1
M, N, O, P
and P2
M, N, O, P
2. Basic Functions
RAID Functions
20
FUJITSU Storage ETERNUS DX500 S4/DX600 S4, ETERNUS DX500 S3/DX600 S3 Hybrid Storage Systems Design Guide (Basic)
Copyright 2019 FUJITSU LIMITED
P3AM-7722-25ENZ0
Summary of Contents for ETERNUS DX500 S3/DX600 S3
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