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This article mainly introduces the relevant knowledge of how to restore the original data after Raid disk array reconstruction, the content is detailed and easy to understand, the operation is simple and fast, and has a certain reference value. I believe you will gain something after reading this Raid disk array reconstruction article on how to restore the original data. Let's take a look.

[description of raid data recovery failure]

A server, the upper layer set up a raid5 disk array, a total of five hard drives are running for the storage of company data, there are no backup files, one day a hard disk on the server is offline, so an external operation and maintenance company is hired to maintain the server. Without knowing the specific circumstances, the personnel of the operation and maintenance company directly rebuilt the four normal hard drives in the server into a brand-new raid5 array. It directly leads to the loss of all the original data of the server.

[server raid array failure analysis]

During the whole process of data loss, the operation that causes the data to be corrupted is to rebuild the raid5. The original array on the client server is raid5, even if a hard disk is offline, it will not affect the use of the server and data integrity. However, the operation and maintenance company rebuilt the raid5 array on four of the hard drives, which will lead to the complete reconstruction of the check block, which means that the original data is bound to be destroyed.

[idea of restoring data]

After the preliminary analysis of the server data recovery engineer, the raid5 of the operation and maintenance company through the four hard disk components is generated according to the double-cycle strategy, the block size is 64, and the number of stripe changes is 16. The 5-disk raid array in the original server also has a double loop; the block size is 128; and the number of stripe changes is 16.

From this we can infer that 1m of the original data will be destroyed in every 3m of the 4 hard drives that can still be identified in the server that has been rebuilt raid. If you want to recover the data in the server, you need to analyze the disconnected hard disk. By comparing the difference between 5 raid arrays and 4 raid arrays, use the data in the offline hard disk to fill the gap of the original data destroyed in each hard disk, and finally reorganize the raid; interpretation file system; export the file. So the data integrity we eventually recover depends on the amount of data in the offline hard drive.

[process for restoring raid array data]

First, mirror backup all the data in the customer's original server.

Second, analyze the image file to get the raid structure before and after the data is destroyed.

Third, compare the raid array structure before and after the data is destroyed, analyze the difference of raid structure, and write a correction program to extract the data. At the same time, the raid5 array is virtually reorganized according to the 5-disk array structure in the customer's original server to generate a group of reorganized image files.

Fourth, extract the data in the offline hard disk, complete the virtual reorganized raid array data, and correct the file system error.

Fifth, export the repaired data to the new space for verification, and the server data recovery engineer delivers the customer verification data after verification.

This is the end of the article on "how to restore the original data after Raid disk array reconstruction". Thank you for reading! I believe you all have a certain understanding of the knowledge of "how to restore the original data after Raid disk array reconstruction". If you want to learn more, you are welcome to follow the industry information channel.

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