Asus PCI-DA2200 - Manual (Page 15)

3-5 ASUS PCI-DA2200 User’s Manual
RAID 5
Striping with
Interspersed Parity
RAID 5 is similar to RAID 3 but the parity data is not stored in one
dedicated hard drive. Parity information is interspersed across the
drive array. In the event of a failure, the controller can
recover/regenerate the lost data of the failed drive from the other
surviving drives.
3.2 Drive Failure Management
3.2.1 Global and Local Spare Drive
Local Spare Drive is a standby drive
assigned to serve one specified logical
drive. When a member drive of this
specified logical drive fails, the Local
Spare Drive becomes a member drive and
automatically starts to rebuild.
Global Spare Drive does not only serve one specified logical drive.
When a member drive from any of the logical drive fails, the Global
Block 1
Block 2
Block 3
Block 4
Block 5
Block 6
Block 7
Block 8
.
.
Logical Drive Physical Disks
Block 1
Parity (3,4)
Block 6
Block 7
Block 2
Block 3
Parity (5,6)
Block 8
Parity (1,2)
Block 4
Block 5
Parity (7,8)
.
. .
. .
.
Striping + non-dedicated Parity
Logical Drive
Local Spare Drive
1 2
3
LS
Assigns one Local Spare
Drive to a logical drive
Logical Drive
1 2
3
X
LS
Local
Spare
Drive
When one member
drive fails, the Local
Spare Drive joins the
logical drive and
automatically starts
to rebuild.
RAID 5
Minimum
Disks required 3
Capacity N-1
Redundancy Yes