AMCC 9650SE 2 Computer Hardware User Manual


 
Red Hot RAID 6
The fastest RAID 6 available
RAID 6 eliminates the risk of data loss if a second hard disk drive fails
while the RAID array is rebuilding. In a 3ware RAID 6 system, two sets
of parity are calculated, written, and rotated across all the drives.
This second simultaneous P + Q parity calculation allows the array
to survive up to two drive failures without losing data, for signicantly
improved fault tolerance. RAID 6-enabled 9650SE controllers deliver
unequaled RAID 6 performance.
RAID 6 represents a sea change in the RAID landscape. It provides
the industry with higher levels of data protection, data availability and
fault tolerance than RAID 5. By assuring data availability following a
second drive failure, users can rest assured that they are enjoying
maximum data protection, both in normal and degraded modes.
And, with RAID 6 enabled 3ware controllers, RAID 6 will not cripple
performance.
RAID 6 Enabled 3ware Controllers
9650SE-8LPML
9650SE-12ML
9650SE-16ML
9650SE-24M8
3ware RAID 6: Two sets of parity data, P + Q, are striped across
disks. RAID 6 safeguards against data loss during rebuild mode
by allowing up to two consecutive drive failures for maximum
fault tolerance.
High capacity systems with eight or more
high capacity drives
For enterprise/mission critical installations
Block 10
Block 7
Block 4
P1 Parity
Disk #1
Block 11
Block 8
P2 Parity
Q1 Parity
Disk #2
Block 12
P3 Parity
Q2 Parity
Block 1
Disk #3
Q4 Parity
Block 9
Block 6
Block 3
Disk #5
Striped Data with Distributed Double Parity —
RAID 6
Host Data
P4 Parity
Q3 Parity
Block 5
Block 2
Disk #4
7