Compaq Infortrend manual RAID 0+1

	RAID 0
	Disk Striping
Figure 1 - 4 RAID 0
LogicalDrive	PhysicalDisks
Block 1	Striping
Block 2
Block 3	Block 1	Block 2
Block 4	Block 3	Block 4
Block 5	Block 5	Block 6
Block 6	Block 7	Block 8

Block 7

Block 8

RAID 0

Minimum	2
Disks required
Capacity	N
Redundancy	No

RAID 0 provides the highest performance but no redundancy. Data in the logical drive is striped (distributed) across several physical drives.

RAID 1

Disk Mirroring

Figure 1 - 5 RAID 1

Lo gi c al Dr i v e

P hy si cal D i s ks

Block 1		Mirroring
Block 2
	Block 1	Mirror 1
Block 3
Block 4	Block 2	Mirror 2
Block 5	Block 3	Mirror 3
Block 6	Block 4	Mirror 4
Block 7
Block 8

RAID 1

Disks required	2
Capacity	N/2
Redundancy	Yes

RAID 1 mirrors the data stored in one hard drive to another. RAID 1 can only be performed with two hard drives. If there are more than two hard drives, RAID (0+1) will be performed automatically.

RAID (0+1)

Disk Striping with Mirroring

Figure 1 - 6 RAID (0+1)

Physical Disks

Logical Drive Striping

RAID (0+1)

Minimum	4
Disks required

Block 1

Block 2

Block 3

Block 4

Block 5

Block 6

Block 7

Block 8

.

.

Block 1		Block 2
Block 3		Block 4
Block 5		Block 6
Block 7	irrorM	Block 8
.		.
.		.
Mirror 1		Mirror 2
Mirror 3		Mirror 4
Mirror 5		Mirror 6
Mirror 7	Striping	Mirror 8
.		.
.		.

Capacity	N/2
Redundancy	Yes

RAID (0+1) combines RAID 0 and RAID 1 - Mirroring and Striping. RAID (0+1) allows multiple drive failure because of the full redundancy of the hard drives. If there are more than two hard drives assigned to perform RAID 1, RAID (0+1) will be automatically applied.

1-4 Infortrend