Solution to Server Partition loss
First, the server disk array data recovery background
The reason for the data loss in this server data recovery case is caused by the misoperation of the administrator. The raid level is raid5 disk array, with a total of 18 hard drives and no hardware failure.
The computer room administrator of a company reinstalled the system on the server, but due to the operation error, the state of the server partition changed, and the original E partition was lost. About 80% of the company's important data was stored in the lost partition. There is an urgent need to restore the operation of the data guarantee company.
Second, the raid5 disk array data recovery process mirrors all the hard disk data in the client server to the server data recovery special storage server for later analysis and data recovery of the raid array, and the failed server restores the original disk array state and returns it to the customer. Use the server data recovery tool independently developed by North Asia to analyze the mirrored customer data before data recovery. Or use other data recovery aids to search file id to analyze the raid array disk order, stripe size and other basic information of the disk array (Note: this operation is risky and must not be operated in the original data). Reorganize the raid array according to the raid information obtained from the analysis, and locate the partition starting position of the xfs file system in the reorganized raid array; (note: XFS INODE number: variable length digit representation, composed of three parts: starting block group number + starting block number + intra-block INODE number. The bit lengths of the starting block number and the INODE number within the block are specified by the parameters in SUPERBLOCK. The server data recovery engineer verifies the integrity and correctness of the file system, and the results show that the xfs file system header is lost very quickly, some nodes are lost, and the directory entries are lost. According to the super block backup and the directory tree structure in the file system, the super block is repaired and restored (the process is brief). Repair the lost nodes and directory items in the xfs file system; repair and reconstruct the lost nodes and directory items. After the above repair work is completed, you can write a Mini Program to parse the file system and extract data.
4. Server data recovery results
Because the super block and some nodes and directory items in the head of the file system of the server are lost, the super block is repaired and restored according to the super block backup and the directory tree structure in the file system. After the lost nodes and directory items are repaired and reconstructed, the file system can be completely restored. And because the customer did not do any destructive operations to write to the storage after the data was lost, most of the data and file system information remained intact, and the server data was 100% restored.
