| 摘要 |
<p>A backup driver generates a backup copy of a main storage medium, such as a hard disk, on a backup storage medium without interfering with access to the files on the main storage medium by applications running on the computer system. The backup driver is loaded at boot time to gain access to the main storage medium on a sector level that is not blocked by the read-write exclusive locks imposed on the files on the main storage medium by the applications. When a scheduled backup time arrives, the backup driver begins to copy the main storage medium sector-by-sector to the backup storage medium. At the same time, the backup driver monitors I/O events on the main storage medium to see whether the I/O events change any sector within the range of sectors already copied to the backup storage medium. If a sector within that range of copied sectors is changed, the backup driver recopies that sector to the backup storage medium to ensure consistency between the main storage medium and the backup storage medium. The backup driver continues to copy the sectors on the main storage medium to the backup storage medium until all sectors on the main storage medium are copied, at which time the backup operation is complete. Because the backup operation is performed on a sector level rather than on a file level, it does not depend on the file structures on the main storage medium.</p> |
