RAID LEVEL 0: Striped Disk Array without Fault Tolerance
RAID Level 0 requires a minimum of 2 drives to implement
RAID LEVEL 1: Mirroring & Duplexing
For Highest performance, the controller must be able to perform two concurrent separate Reads per mirrored pair or two duplicate Writes per mirrored pair.
RAID Level 1 requires a minimum of 2 drives to implement
RAID LEVEL 2: Hamming Code ECC
Each bit of data word is written to a data disk drive (4 in this example: 0 to 3). Each data word has its Hamming Code ECC word recorded on the ECC disks. On Read, the ECC code verifies correct data or corrects single disk errors.
RAID LEVEL 3: Parallel Transfer with Parity
The data block is subdivided ("striped") and written on the data disks. Stripe parity is generated on Writes, recorded on the parity disk and checked on Reads.
RAID Level 3 requires a minimum of 3 drives to implement
RAID LEVEL 4: Independent Data Disks with Shared Parity Disk
Each entire block is written onto a data disk. Parity for same rank blocks is generated on Writes, recorded on the parity disk and checked on Reads.
RAID Level 4 requires a minimum of 3 drives to implement
RAID LEVEL 5: Independent Data Disks with Distributed Parity Blocks
Each entire data block is written on a data disk; parity for blocks in the same rank is generated on Writes, recorded in a distributed location and checked on Reads.
RAID Level 5 requires a minimum of 3 drives to implement
RAID LEVEL 6: Independent Data Disks with Two Independent Parity Schemes
Two independent parity computations must be used in order to provide protection against double disk failure. Two different algorithms are employed to achieve this purpose.
RAID Level 6 requires a minimum of 4 drives to implement
RAID LEVEL 10: Very High Reliability Combined with High Performance
RAID Level 10 requires a minimum of 4 drives to implement
RAID LEVEL 50: High I/O Rates & Data Transfer Performance
RAID Level 50 requires a minimum of 6 drives to implement
RAID LEVEL 0+1: High Data Transfer Performance
RAID Level 0+1 requires a minimum of 4 drives to implement
RAID Level 0 requires a minimum of 2 drives to implement
RAID LEVEL 1: Mirroring & Duplexing
For Highest performance, the controller must be able to perform two concurrent separate Reads per mirrored pair or two duplicate Writes per mirrored pair.
RAID Level 1 requires a minimum of 2 drives to implement
RAID LEVEL 2: Hamming Code ECC
Each bit of data word is written to a data disk drive (4 in this example: 0 to 3). Each data word has its Hamming Code ECC word recorded on the ECC disks. On Read, the ECC code verifies correct data or corrects single disk errors.
RAID LEVEL 3: Parallel Transfer with Parity
The data block is subdivided ("striped") and written on the data disks. Stripe parity is generated on Writes, recorded on the parity disk and checked on Reads.
RAID Level 3 requires a minimum of 3 drives to implement
RAID LEVEL 4: Independent Data Disks with Shared Parity Disk
Each entire block is written onto a data disk. Parity for same rank blocks is generated on Writes, recorded on the parity disk and checked on Reads.
RAID Level 4 requires a minimum of 3 drives to implement
RAID LEVEL 5: Independent Data Disks with Distributed Parity Blocks
Each entire data block is written on a data disk; parity for blocks in the same rank is generated on Writes, recorded in a distributed location and checked on Reads.
RAID Level 5 requires a minimum of 3 drives to implement
RAID LEVEL 6: Independent Data Disks with Two Independent Parity Schemes
Two independent parity computations must be used in order to provide protection against double disk failure. Two different algorithms are employed to achieve this purpose.
RAID Level 6 requires a minimum of 4 drives to implement
RAID LEVEL 10: Very High Reliability Combined with High Performance
RAID Level 10 requires a minimum of 4 drives to implement
RAID LEVEL 50: High I/O Rates & Data Transfer Performance
RAID Level 50 requires a minimum of 6 drives to implement
RAID LEVEL 0+1: High Data Transfer Performance
RAID Level 0+1 requires a minimum of 4 drives to implement
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