What is the difference between hard disk doing RAID RAID1 2 3 4 5?

The main differences are as follows:

1. Data security is different. The security of this hard drive mode is very high, and the data security of RAID 1 is the best of all RAID levels. However, the disk utilization rate is only 50%, which is the lowest of all RAID levels.

2. The concept is different. Conceptually, RAID 2 is similar to RAID 3 in that both strips data is distributed across different hard disks, with blocks in bits or bytes.

3. The verification information is in different ways. Use a single disk to store parity.

Information. If a disk fails, the parity disk and other data disks can regenerate the data. If the odd and even disk fails, the data usage will not be affected.

RAID 3 provides a good transfer rate for large amounts of sequential data, but for random data, parity disks can become a bottleneck for write operations.

4. Different ways of data access. RAID 4 is very similar to RAID 3, except that its access to data is carried out on a per-block basis, that is, on a per-disk basis, one disk at a time. As you can see from the diagram, RAID3 is one bar at a time, while RAID4 is one bar at a time.

Its characteristics are similar to RAID3, but it is much more difficult than RAID3 when it fails to recover, the controller design is much more difficult, and the efficiency of accessing data is not very good.

5. The readout efficiency is different. As you can see from its schematic, its parity code is present on all disks, where p0 represents the RAID 5 parity value in zone 0, and the other meanings are the same. The readout efficiency of RAID 5 is very high, the write efficiency is average, and the block collective access efficiency is good.

Because parity codes are on different disks, reliability is improved and a single disk is allowed to fail. RAID 5 also uses the check digit of the data to ensure the security of the data, but it does not store the check digits of the data on a separate hard disk, but stores the check digits of the data segments on each hard disk.

Redundant arrays of independent disks (RAID) use multiple disks to improve read and write performance or data security.

The commonly used RAID modes and their basic characteristics are as follows;

RAID0 can be simply understood as combining multiple hard disks into one large hard disk. Since data can be spread out and written to multiple disks at the same time, high read and write performance can be obtained. The disadvantage is that if any hard drive in the array is damaged, all data is lost.

RAID0 requires at least two hard drives.

RAID1 can be simply understood as the use of multiple hard disks for duplicate mirroring. This array provides excellent data security, and data loss will only result in a complete corruption of all hard drives. Raid1 requires at least two hard drives.

On the basis of the ordinary array, RAID2 uses a dedicated disk to store the ECC check code of the data, and through the Hemming code check, it can check and correct the error in the case of data error to ensure the correctness of the output.

RAID 3 is similar to RAID 2, but only provides error correction and does not provide error correction.

RAID 4 can be understood as the big data version of RAID 3. It's much more difficult than RAID 3, the controller is much more difficult to design, and it's not as efficient at accessing data.

RAID 5 can be understood as the distributed data version of RAID 3. Because the data is distributed and stored, because the access is more efficient.

RAID 0 refers to disk striping technology.

This is done by segmenting data and writing to multiple disks at the same time. Its advantage is that the disk can realize parallel input and output, and improve the disk read and write speed, but this technology has no fault tolerance;

RAID 1 stands for Disk Mirroring.

The implementation method is to simply copy the data on one disk to the second disk or the equivalent storage device to realize the redundancy of the data, and its advantage is that the complete redundancy of the data is realized, and the fault tolerance performance is excellent, but this technology does not improve the disk read/write speed and the cost is high; RAID 2-5 refers to the combination of disk segmentation and disk redundancy, where RAID 2 refers to disk segmentation combined with HAMM Code error correction technology, RAID 3 refers to disk segmentation plus dedicated parity disks, RAID 4 refers to disk segmentation plus dedicated asynchronous parity disks, and RAID 5 refers to disk segmentation plus even checks distributed across each disk. These technologies combine the advantages of disk segmentation and disk mirroring, which require a disk array to have at least three disks, allow for one disk failure due to the use of check code technology for data redundancy, and improve disk read/write capabilities due to the use of disk segmentation technology. RAID 5 technology is currently the most widely adopted.

1. RAID 0 is to merge multiple (at least 2) hard disks into one logical disk, and the data is read and written to each hard disk at the same time, and different hard disks write different data, which is fast.

2. RAID1 is to read and write to 2 hard disks (the same data) at the same time. Emphasize the security of your data. Relatively wasteful.

3. RAID5 also combines multiple (at least 3) hard disks into one logical disk, and parity information will be established when data is read and written, and the parity information and corresponding data are stored on different disks. When a disk of RAID 5 is corrupted, the remaining data and the corresponding parity information are used to recover the corrupted data. Equivalent to a combination of RAID0 and RAID1.

4. RAID10 is RAID1+RAID0, with high speed requirements, complete fault tolerance, and of course, many times the money is also the most.

RAID was proposed by a professor at the University of California, Berkeley, in 1988. RAID is an abbreviation for Redundent Array of Inexpensive Disks, which literally translates to Cheap Redundent Disk Array, also known simply as Disk Array.

1. In terms of the number of hard disks, RAID 0 must have at least 2 hard disks. RAID 1 has at least 2 hard disks and an even number of hard disks. RAID 5 with at least 3 hard drives.

2. In terms of capacity, the capacity of RAID 0 is the sum of the capacity of all hard disks. RAID 1 is half of the total capacity of all hard disks, and RAID 5 is the sum of all hard disks minus the capacity of one hard disk.

RAID 0 is the use of all hard disks as one logical storage space. RAID 1 dedicates half of the hard disk space to store data mirroring to ensure the integrity and reliability of data. RAID 5 uses a hard disk to verify data storage to ensure the integrity of data storage.

The things you see in the hard disk space are getting deeper and deeper, and the difference between them is actually not too big, and there is still no obstacle in real-world applications.