Typically, most data restore systems stipulate that the data should be restored to computing systems that have the same or similar software environments (operating system, applications etc). Bare metal restore is a data recovery and restoration technique that allows the restoration of data to a computer system that can have software/hardware components that are entirely different from the system from which the backup of data was done. The restoration process is “bare metal” or without requirements of any kind.
Bare metal restores are different from disk image restores.
In disk image restores, only a copy of the disk image and the restoration software are stored on the computer that is backed up.
In bare metal restore, the operating system, the applications and the data components are stored in the image file.
Bare metal disk imaging applications ease the process of bare metal restore. The images generally contain snapshots of all the software components that were present at the time of backup and restoration, merely replicates the entire environment along with the data to the new disk. For instance, the ‘dd’ utility on a Linux Boot CD is often used to copy entire file systems between disk images, including disk partitions. The disk image resulting from this backup can be used for bare metal restore to create a new partition with the same or larger size. Microsoft’s Wbadmin of Windows Server 2008 supports bare metal recovery. Users can use this utility to recover their system into a HyperV virtual machine.
Point in time restores are possible with bare metal restores. The entire system can be restored to the last known good state with one single restore process. It is extremely useful for disaster recovery, as the disk image can be used to recreate the entire system with new hardware, at an entirely new geographical location, using web-based application access.
Bare metal restore processes differ in implementation. Consequently, the restoration process is often referred to as an art rather than as a science. Some Cloud and online backup services provide little or no support for bare metal restores on to entirely new hardware. Asigra is one of online backup software that has bare metal restore capabilities.
The storage configurations of the servers may also vary and you must ascertain that the configurations are supported in the new hardware you will be using for restoration. For instance, it is important to check out whether the basic partition table type storage configurations are supported or the whether there is support for converting “ext3” to a “ReiserFS” in a Linux file system and whether it works on LVM or MD devices and so on.