Disk array RAID Technology comparison

RAID is all called Redundant Array of independent disks (redundant array of independent Disks), the basic idea is to combine a number of relatively inexpensive hard drives to become a hard disk array group, so that performance reaches even more expensive, large capacity of the hard disk. RAID is usually used on a server computer and uses the exact same hard drive to form a logical sector, so the operating system will only treat it as a hard disk. In each RAID level, the most widely used is RAID0,RAID1,RAID10,RAID5.

RAID-0 the data into a set of disks in a striped order. RAID-0 does not provide redundancy, but it provides excellent throughput performance because read-write data is processed concurrently on each disk in a set of disks, and throughput performance is much more than the read and write of a single disk.

RAID-1, each write operation will be written two copies to the data disk and check disk, each pair of data disks and check disk becomes a mirrored disk group. You can also improve throughput performance when you read data in a concurrent manner. If there is an error in a disk in the mirrored disk group, the data can be obtained from another disk without affecting the performance of the system, and then a spare disk is used to copy the data from the healthy disk and the two disks form a new mirror group.

Raid1/0, that is, the combination of RAID1 and RAID0, both do the mirror and do strip, the data first mirror and then do the stripe. This data storage ensures both reliability and throughput performance.

RAID-0/1 is also a combination of RAID0 and RAID1, but it is mirroring the striped data. But with

RAID10, the loss of one disk equates to the loss of the entire mirrored stripe, so once the mirror disk fails, the storage system becomes a RAID-0 system (that is, only striped).

RAID-5 is to spread the data validation cycle across the disks, which, like RAID-0, disperses the data stripe

To a set of disks, but at the same time it generates checksum data for redundancy and fault-tolerant use. The check disk contains the number of all bands

The verification information of the data. RAID-5 Officer information is written to each disk in the stripe disk group, that is, each disk has both data information and checksum information, the performance of the RAID-5 is due to the data stripe, but the failure of one disk will cause the whole system to decline, because the system will assume the reading and writing tasks, Rebuild and calculate data on failed disks, and restore the health of the entire system using an alternate disk to rebuild the failed disk's data.

In terms of a common application, it is required that the storage system has good IO performance and the protection of data security, so raid10 and RAID5 should be the object of our attention.

If we are using disk array raid, accidentally data loss situation, we must first seek the help of technical center. The Shanghai Shield Data Recovery Center is one of our trusted institutions, the most professional technology will be able to help us solve the problem of RAID data loss.

Disk array RAID Technology comparison