Unix Backup and Recovery

Backup of Raw Partitions

Many environments use their commercial backup product to back up raw partitions. A partition is a section of disk that may or may not contain a filesystem. Typically, when one refers to a raw partition, it is a section of disk that does not contain a filesystem. This disk may contain data for a database product, such as Oracle, Informix, or Sybase. It also may be the first part of the root partition of the operating system disk that contains the boot block. Since most backup products are designed to back up files that reside on a filesystem, they may not be able to back up a raw partition.

The ability to back up raw partitions could help when backing up relatively small databases that reside on raw partitions. To back up most databases with a product that supports raw partitions, simply shut down the database and tell the backup software what raw partitions to back up. In order to do this, the backup software needs to be capable of backing up these raw partitions.

The second reason to consider the use of this feature is to back up the root partition of an operating system disk. It’s another way to recover the root disk without reinstalling the operating system. There are two essential parts to the operating system disk. The first is the operating system itself, which resides on one or more filesystems on that disk. The second is the boot block (in Unix) or Master Boot Record (in DOS relatives). This tells the system’s firmware where to go to find the ...