[server data recovery] data recovery case of a Dell server crash caused by raid damage

Server failure ：

A certain type of Dell server is due to raid Damage and collapse , Because the server data is classified , The administrator contacts our data recovery center for data recovery .

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Server fault detection ：

The data recovery engineer brings relevant equipment to the site to test the server , It is found that the cause of server crash is raid Some hard disks in the array are disconnected . After physical inspection of all disks, the hardware engineer found no physical faults and bad tracks . Then the data recovery engineer mirrors all disks in the failed server to the prepared data recovery service platform with the help of data recovery software .

Server data recovery process ：

1、 Analyze the failed server RAID structure .

Of the failed server LUN All based on RAID Array group , Therefore, to recover the server data, we must first analyze the underlying server RAID Information , Then, according to the information obtained from the analysis, reconstruct the original RAID Group . The server data recovery engineer is right raid After analyzing the array, it is found that two hard disks in the server are offline . because 6 Plate and 10 Plates belong to Hot Spare, But when the server fails 6 Number Hot Spare Replaced the disconnected 5 Hard disk No , can 10 Disk number is not enabled for unknown reasons . Although the server was successfully activated 6 Number plate Hot Spare, but RAID A hard disk is still missing in , The data was not successfully synchronized to 6 Hard disk No . Server data recovery engineers continue to analyze other hard disks , Get the distribution law of data in the hard disk ,RAID The size of the strip , Information such as the order of each disk .

2、 restructuring raid Analyze the order of the drop panel .

According to the obtained raid Information , Data recovery engineers use the... Independently developed by North Asia RAID Virtual program virtual reorganization failure server raid. After the reorganization, analyze the order of the two offline hard disks in the server . By checking , The server data recovery engineer found that the data of one hard disk on the same strip was obviously inconsistent with other hard disks , It is preliminarily judged that this hard disk may be the first to be disconnected . Developed independently through North Asia RAID The verification program checks this strip , Finally determine the hard disk that drops the line first .

3、 analysis RAID In group LUN Information .

Based on the obtained raid Information , Disc dropping sequence , Reorganize according to the analysis results raid. analysis LUN stay RAID Allocation information in the group and LUN Allocated data block MAP. Then, based on this information, use the self-developed raid Data recovery program , explain LUN The data of MAP And export LUN All data for .

4、 explain ZFS File system and fix .

Use the... Independently developed by North Asia ZFS File system interpreter for generated LUN Do file system interpretation , Parse all file nodes and directory structures .

Server data recovery results ：

The server administrator verifies the data in person , All data is normal 、 complete , This data recovery is successful .