With the development of Internet, data security has become an inevitable problem for enterprises. The data security of server is more important, and the selection of server array is a way to protect data. So how to choose?
The array of server refers to raid, which combines multiple hard disks into a logical hard disk. Therefore, the operating system will only treat it as a physical hard disk. According to the type of array, it has different characteristics.
Basic functions of raid
1. Expand the capacity and provide the ability of reading and writing.
2. The redundancy protection of data is realized by mirroring or storing parity information.
Common types of raid
Raid0, also known as bandset, connects more than two disks in parallel to form a large capacity disk.
When storing data, it is stored in these disks after segmentation. Because read and write can be processed in parallel, raid0 is faster in all levels.
But raid0 has neither redundancy nor fault tolerance. If a disk is damaged, all data will be lost.
More than two groups of N disks mirror each other. As long as one disk is normal, it can maintain operation with high reliability.
Its principle is to store data on the main hard disk and write the same data on the mirror hard disk at the same time.
When the primary hard disk (physical) is damaged, the mirror hard disk will replace the primary hard disk.
Because there is a mirror hard disk for data backup, the data security of RAID1 is extremely safe at all RAID levels.
However, no matter how many disks are used for RAID1, the capacity of one disk is the lowest level of disk utilization in all raid.
Combined with raid0 and RAID1, RAID5 needs at least three hard disks. Instead of backing up the stored data, RAID5 stores the data and the corresponding parity information on each disk of RAID5, and the parity information and the corresponding data are stored on different disks.
When a disk data of RAID5 is damaged, the remaining data and the corresponding parity information can be used to recover the damaged data.
RAID10 is to divide the data first and then mirror, and then divide all hard disks into two groups. It is regarded as taking RAID1 as the low combination, and then each group of RAID1 is regarded as a “hard disk” combination to operate as raid0.
Generally speaking, in order to provide high program data reading and writing ability and increase storage space, in addition to using high-speed hard disk and large capacity hard disk, raid0 can also be used; If you want to protect data and backup data, you can also do RAID1 real-time backup in addition to your own regular backup to the local. If you have higher requirements, you can also do RAID5 and RAID10.
Editor in charge: CC