2.
Basic Functions
RAID Functions
●
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
A
A
E
I
M
P1
Drive#0
Drive#1
Fujitsu Storage ETERNUS DX100 S4/DX200 S4, ETERNUS DX100 S3/DX200 S3 Hybrid Storage Systems Design Guide (Basic)
Data writing request
A
B
C
D
B
C
B
C
F
G
P1
P2
J
P1
I, J, K, L
P2
M, N, O, P
M, N, O, P
Drive#2
Drive#3
Parity for data A to D: P1
Parity for data E to H: P1
Parity for data I to L: P1
Parity for data M to P: P1
Copyright 2023 Fujitsu Limited
D
Create parity data
P1
P2
D
A, B, C, D
P2
E, F, G, H
E, F, G, H
I, J, K, L
K
N
O
Drive#4
Drive#5
and P2
A, B, C, D
and P2
E, F, G, H
and P2
I, J, K, L
I, J, K, L
and P2
M, N, O, P
20
A, B, C, D
H
L
P
A, B, C, D
E, F, G, H
M, N, O, P
P3AM-7642-32ENZ0