Linux hardware RAID detailed system function diagram

RAID-0 (stripe mode)

Characteristics:

Concurrency can be achieved while reading and writing, so it is best to read and write, each disk holds part of the complete data, and reads in parallel, with more disks and faster reads and writes.

Because there is no redundancy, one hard disk loses all data loss.

At least two hard disks can form a RAID0 array.

Capacity:

The sum of all hard drives. Disk Utilization is 100%

Production Application Scenarios

1. Multiple identical RS node servers under load Balancer cluster

2. Distributed file storage The following master node

3, MySQL master-slave replication of multiple slave server

4, high performance requirements, low redundancy requirements of the relevant business

RAID-1: Mirroring (mirrored volume)

Characteristics:

Requires at least two drives

The raid size is equal to the smallest capacity in two raid partitions (preferably dividing the partition size into one)

The data is redundant, simultaneously writes two hard disks in the storage, realizes the data backup;

Disk utilization is 50%, that is, 2 100G of disk composition RAID1 can only provide 100G of free space.

RAID-5

Characteristics:

The use of parity check, high reliability

The disk checksum is hashed to a different disk, increasing the read and write rate.

Data cannot be restored only if two disks are lost at the same time

At least three hard drives and the hard disk size should be equal to make up the RAID5 array.

Capacity:

The sum of all HDD capacity minus the capacity of one of the hard drives

The subtracted capacity is allocated to different areas of the three hard drives to hold data validation information.

RAID10 (RAID1+RAID0)

Characteristics:

is now a more common type of disk array level,

It is a good fault-tolerant, high efficiency of reading and writing data, but relatively high funding.

Backup and concurrent access to data, strong reliability.

D1, D2 constitute an array Raid1, wherein the D1 is the data disk, D2 is the backup disk;

D3, D4 also form an array Raid1, wherein the D3 is a data disk, D4 is a backup disk;

On this basis, D1, D2 as a whole, will D3, D4 also as a whole

A RAID0 array is formed between the two whole.

This will not only read the data very quickly, but also the speed of concurrent writes will increase as the disk grows faster.

At least four hard drives and each hard disk size should be equal to make up the RAID10 array.

Capacity

Half of all hard drive capacity (half write data, half to back up data).

RaidSummary

(from node) RAID0

Read and write fast, without any redundancy

MySQL Slave (database from library, little brother), cluster node RS

(Monitoring, important) RAID1

100% redundancy, Mirror read and write performance generally

High cost alone, data important, and can not downtime of business, monitoring, system disk

(Normal business) RAID5

Have a certain performance and redundancy, can be bad piece of disk, read good performance is not high write performance

General business can be used

(primary node of the database) RAID10

Read and write fast, 100% redundancy costs high performance and redundancy requires a good business. The primary library of the database and the storage

Linux hardware RAID detailed system function diagram