Compaq Infortrend manual What are the RAID levels?, 1 RAID Levels

then distributes data segments to its member drives according to the specific RAID level it is composed of.

The member logical drives can be composed of the same RAID level or each of a different RAID level. A logical volume can be divided into a maximum of 64 partitions. During operation, the host sees a non-partitioned logical volume or a partition of a logical volume as one single physical drive.

1.3RAID Levels

RAID stands for Redundant Array of Independent Disks. Using a RAID storage subsystem has the following advantages:

•Provides disk spanning by weaving all connected drives into one single volume.

•Increases disk access speed by breaking data into several blocks when reading/writing to several drives in parallel. With RAID, storage speed increases as more drives are added as the channel bus allows.

•Provides fault-tolerance by mirroring or parity operation.

What are the RAID levels?

Table 1 - 1 RAID Levels

RAID Level	Description	Capacity	Data Availability
NRAID	Non-RAID	N
RAID 0	Disk Striping	N	==NRAID
RAID 1 (0+1)	Mirroring Plus Striping (if	N/2	>>NRAID
	N>1)		==RAID 5
RAID 3	Striping with Parity on	N-1	>>NRAID
	dedicated disk		==RAID 5
RAID 5	Striping with interspersed	N-1	>>NRAID
	parity		==RAID 5
RAID 10	Striping with RAID 1	/	>>NRAID
(Logical Volume)	logical drives		>>RAID 5
RAID 30	Striping with RAID 3	/	>>NRAID
(Logical Volume)	logical drives		>>RAID 5
RAID 50	Striping with RAID 5	/	>>NRAID
(Logical Volume)	logical drives		>>RAID 5

NOTE: Drives on different channels can be included in a logical drive and logical drives of different RAID levels can be used to

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