The process of recovering data by scraping method

Background of the server data recovery case:

–The server raid disk array group is paralyzed. There are 3 hard disks in the disk array. At present, one hard disk has a red alarm light. The data that needs to be restored is the D disk. Database data. After the storage failure, the administrator restarted the server, which caused the previously offline hard disk to go back online and synchronize data. Fortunately, a forced shutdown was performed before the synchronization was completed.

Server data recovery process:

  • –The server data recovery engineer first carried out a read-only mirror backup of the three hard disks in the array, and found this during the backup process. The three hard disks in the server can be recognized and read normally, and no bad sectors are found on the hard disk
  • –Then the server data recovery engineer conducted a detailed analysis of the completed image file, and the raid basic The information undergoes virtual raid reorganization and XOR verification, detailed analysis of the backup image file, reorganization of the raid structure, and XOR verification, but because the administrator has performed a synchronization operation after the data is damaged, this operation will The data is damaged, so when the XOR check is performed, the result is partial check passed, indicating that the data is damaged.
  • –The server data recovery engineer further analyzed the RAID array and tried a variety of hard drives offline to perform data extraction operations, but the data extracted by each attempt was the same . I had to first analyze and repair the dat file in the E partition. I hope that the data can be recovered by finding the backup file, but the result of the data recovery is still that the file is damaged. The data recovery engineer analyzes the aggregated dat fragments, verifies the integrity of the dat data, and the underlying structure shows damage.
  • –The data recovery engineer tried several methods for data extraction but failed. To restore the damaged data, the only way to restore the original data of the server is through splicing fragments. Make one final attempt. The server data recovery engineer scans the data page of the free space of the D partition, analyzes and aggregates all the scanned fragments one by one, and simply verifies the integrity and validity of the aggregated file fragments, and then exports the data records in the backup file to Engineer’s new database. Connect to the database through the upper-level application to verify data availability, the database file can be loaded normally, and the user account in the upper-level application software is normal, and normal data query can be performed. The data recovery was successful this time

Summary of server data recovery case:

During the recovery process, two SealLib database backup files were found on Disk E. However, a small part of the page structure in the backup file data is damaged. In the results of the D partition scan, the data fragments found more continuous data fragments, and the fragments are available. Through the integration and splicing of D partition fragments and E partition backup files. The data parsed by the final repair can support the normal use of the entire application, and the upper-level application can query the database content normally.

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