●
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.
●
RAID6-FR (Striping with Double Distributed Parity which Provides High-Speed Rebuild Capabilities)
Distributing multiple data groups and reserved space equivalent to hot spares to the configuration drives
makes it possible to recover from up to two drive failures. RAID6-FR requires less build time than RAID6.
Figure 2
RAID6-FR Concept
RAID6-FR ((3D+2P) × 2 + 1HS)
H
FHS
V
E
I
S
C
J
A
K
FHS
X
W
F
FHS
N
T
G
Q
U
D
O
FHS
B
R
FHS
P
FHS
M
L
A
B
C
D
Data writing request
A
B
C
D
Create parity data
Create parity data
P1
A, B, C
P1
P, Q, R
P2
P, Q, R
P1
V, W, X
P1
M, N, O
P2
M, N, O
P1
D, E, F
P2
J, K, L
P2
D, E, F
P1
J, K, L
P1
S, T, U
P2
G, H, I
P1
G, H, I
P2
S, T, U
P2
A, B, C
P2
V, W, X
Drive#0
Drive#1
Drive#2
Drive#3
Drive#4
Drive#5
Drive#6
Drive#7
Drive#8
Drive#9
Drive#10
Parity for data A, B, C: P1
A, B, C
and P2
A, B, C
Parity for data D, E, F: P1
D, E, F
and P2
D, E, F
Parity for data G, H, I: P1
G, H, I
and P2
G, H, I
Parity for data J, K, L: P1
J, K, L
and P2
J, K, L
Parity for data M, N, O: P1
M, N, O
and P2
M, N, O
Parity for data P, Q, R: P1
P, Q, R
and P2
P, Q, R
Parity for data S, T, U: P1
S, T, U
and P2
S, T, U
Parity for data V, W, X: P1
V, W, X
and P2
V, W, X
:
Fast recovery Hot Spare: FHS
2. Basic Functions
RAID Functions
34
Design Guide
Содержание ETERNUS DX S5 Series
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