Low-level disk image or so-called Bare Metal backups, are byte-level copies of a full partition or even a complete logical or physical disk. Some utilities will only include used sectors in the copy, thus reducing the size and speed of the backup and restore operations, but this is not always the case. When restoring such a backup, some sort of media, such as a live CD, is required in order to boot up the software to restore the image.
Full disk byte-Ievel backups are useful ifyou need to duplicate or restore a system quickly, as long as the disk being restored is the same or larger. Partition backups of this type may also be done, but in order to restore them you will need some way to restore the partition information to the disk partition table.
Low-level backups are useful in two situations:
- When a system must be replaced and restored quickly with identical hardware
- When a system needs to be duplicated many times on identical hardware
A good example of the latter is when a company provides workers with preconfigured systems all with identical or nearly identical initial configurations. In this case, itis easy just to restore the disk from a standardized copy whenever a new system is required or an old one needs to be returned to its original condition for a new employee.
