International Business Machines Corporation
File level access to block level incremental backups of a virtual disk

Abstract:

For accessing files from block-level backups of a virtual disk, a system, method, computer program product and apparatus are disclosed. The system includes an apparatus with a changed block module that determines changed blocks between a previous and a current block-level backup of a virtual disk. A mapping module maps logical clusters of the virtual disk to the changed blocks and identifies files corresponding to the logical clusters. A changed file module designates files corresponding to the logical clusters as changed files, unless current attributes of files for the current backup match attributes of the files in a backup file index corresponding to the previous backup. The changed file module stores the current attributes and extents for changed files within blocks of a backup storage device for updating in the backup file index. The method and computer program product perform these functions and may use the system and the apparatus.