Linux Commands: Raid learning

raid Introduction:       

RAID (Redundant array of independent/inexpensive Disks) is known as a redundant array of independent inexpensive disks.

The basic principle of RAID is to combine multiple inexpensive small disks to improve fault tolerance and access speed.

RAID level description; :raid Comparison of text )

Commonly used RAID classes are RAID 0, RAID1, RAID 5, and RAID 6, plus two-in-one RAID 10 or RAID 50. Let's compare the advantages and disadvantages of these RAID levels first:

Relative disadvantage of RAID level relative advantages
RAID 0 Access speed is the fastest without fault tolerance (stripe)
RAID 1 full fault-tolerant cost (mirrored)
RAID 5 with multi-tasking and fault-tolerant features when writing overhead
RAID 10 is fast and full fault-tolerant cost is high

RAID 6

RAID 6 adds a second independent parity information block compared to RAID 5. two independent parity systems use different algorithms , and the data is very reliable, even if two disks fail at the same time without affecting the use of the data. However, RAID 6 requires more disk space allocated to parity information and a greater write loss than RAID 5, so "write performance" is very poor. Poor performance and complex implementations allow RAID 6 to be rarely used in practice.

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Linux commands: Raid learning