RAID0/RAID1/RAID5/RAID10 of RAID Literacy articles

In order to meet different data transmission efficiency and security requirements, we have known RAID0, RAID1, RAID2, RAID3, RAID4,

RAID5, RAID6, RAID10, RAID50 and other different levels of RAID, the following briefly commonly used RAID0/1/5/10 characteristics and the scope of application.

RAID0: RAID0, also known as stripe mode, is to tie multiple disks together and become a large disk. When the data is stored, it presses the data on the disk

Number to fragment, and then write the data into these disks at the same time, so at all levels, the speed of the RAID0 is the fastest. But RAID0 didn't.

There is redundancy, and if one disk (physical) is damaged, all data will be lost.

As a result, RAID0 is not suitable for mission-critical environments, but is well suited for video, image authoring, and editing.

The RAID0 logical structure is as follows:

RAID1: RAID1 also becomes a mirror that copies the data on one disk to the other disk completely. If there is an error in the data on a disk,

Or if the disk has a bad path, the other disk can recover the data loss and system interruption caused by the disk failure. In addition, RAID1 can also

To achieve duplex-that is, the entire controller can be copied, so that data can be protected when a disk failure or controller failure occurs.

The disadvantage of mirroring and duplex is that there is a need to multiply the number of drives to replicate the data, but the read and write performance of the system does not improve.

The RAID logical structure is as follows:

RAID5: RAID5 is also called a stripe with distributed parity, where each stripe has the equivalent of a "block" that is used to store the odd-even

-bit Compared to other RAID levels, the RAID5 distributes parity information across all disks, rather than on a single disk, greatly reducing the odd-even school

The burden of inspection, despite some loss of capacity, but RAID5 can provide a better overall performance, it is also widely used as a

Disk array scenarios.

The RAID5 logical structure is as follows:

RAID10: RAID10 can be subdivided into raid1+0 and raid0+1.
Raid1+0 is to mirror and then split the data, all the hard drives into two groups, as the lowest combination of RAID0, and then the two groups respectively as RAID1

, Raid1+0 has a good reading speed and has a higher data protection than RIAD0.

Raid0+1 is the same as the Raid1+0 program, is the first partition and then mirror the data to two groups of hard disks. It divides all the hard drives into two groups, turning them into RAID1

, and the two groups of hard disks are considered RAID0 operations respectively. Raid0+1 has a faster reading and writing speed than raid1+0, but there are a number of things that will make

The chance that the entire hard disk group will stop running, as long as the same set of hard disks is completely destroyed, the raid0+1 stops functioning, and raid1+0 can sacrifice

Raid0+1 the advantages of the normal operation.

RAID cleverly leverages both the speed of the RAID0 and the protection of the RAID1, but its disadvantage is that it requires a large number of hard drives and must have at least four

More than one even drive can be used.