HP P4000 Disk Array

RAID 0 Stripe

Provides maximum capacity and optimal performance, but does not provide data protection. If you select this option, data is lost when the hard drive that is storing the data fails. However, because there is no logical drive capacity for redundant data, this method provides optimal capacity. This method provides the best processing speed because it can simultaneously read two strips on different hard drives and no parity drives.

RAID 1 Mirroring

Provides a good combination of data protection and performance, and RAID 1 or drive mirroring stores the same dataset on at least two hard drives, creating fault tolerance. The number of drives for RAID 1 must be even. RAID 1 and raid1+0 (10) are the most cost-tolerant methods, because they require 50% drive capacity to store redundant data. RAID 1 mirrors the contents of one hardware drive in the array to another hard drive, and if one of the hard drives fails, the other provides a backup copy of the file, and normal system operations are not interrupted.

RAID 1+0 Mirroring and striped

Best combination of data protection and performance RAID 1 + 0 or drive mirrors store the same data on a minimum of four hard drives to achieve fault tolerance. The number of drives for a RAID 1+0 must be even. RAID 1+0 and RAID 1 are the most cost-tolerant methods, because they require 50% of the drive capacity to redundant data. RAID 1+0 First mirrors the contents of one hard drive in the array to another hard drive, and then strips the data across mirrored pairs. If one of the physical drives fails, the mirrored drive provides a backup copy of the file, and normal system operations are not interrupted. RAID 1+0 can withstand multiple simultaneous drive failures, as long as the failed drives do not mirror each other.

RAID 5

Provides the best combination of data protection and capacity, while providing performance over RAID 6. RAID 5 stores parity data between all the physical drives in the array, allowing more read operations to be performed at the same time. If a drive fails, the controller reconstructs the data from the failed drive using the parity data and the data on its redundant drives. The system will continue to run, except that the performance is slightly reduced unless you replace the failed drive. RAID 5 can only pass through a single drive failure without causing the entire array to fail. He requires that the array contain at least three physical drives. The usable capacity is N-1, where n is the number of physical drives in the logical array.

RAID 6

Provides optimal data protection, which is an extension of RAID 5. RAID 6 uses multiple parity sets to store data, so it can withstand up to 2 drives at the same time. RAID 6 requires a minimum of 4 drives, and performance is less than RAID 5 due to more novelty parity data on multiple drives. RAID 6 uses two disks for parity, and its fault tolerance allows two disks to fail at the same time. The usable capacity is N-2, where n is the number of physical drives in the logical array.

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