Sonnet Technologies Web Management Tool - Manual (Page 78)

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Appendix B - RAID Group Designs
RAID Level 6: Striping, Two Parity Blocks
Distributed Among Drives
RAID Level 6 increases reliability for mission critical
applications by striping both data and dual parity across
multiple drives, writing data and parity blocks across all the
drives in a RAID group. RAID 6 provides can tolerate failure
of two drives and provides redundancy during rebuilds. See
Figure B-9.
The Fusion RX1600Fibre requires at least four drives to build
a RAID 6 group. Two drives per RAID group are used for
parity protection and are unavailable for data.
Disk 1
Data 2
Data 6
Parity 7–9
Parity
10–12
Disk 1
Data 1
Data 5
Data 9
Parity
10–12
Disk 2
Data 3
Parity 4–6
Parity 7–9
Data 10
Disk 3
Parity 1–3
Parity 4–6
Data 7
Data 11
Disk 4
Parity 1–3
Data 4
Data 8
Data 12
RAID Level 6: Striping, Two Parity Blocks
Distributed Among Drives
Stripe 1
Stripe 2
Stripe 3
Stripe 4
Figure B-9