Note

You can download this article as a PDF

Bare Metal Recovery for Linux

Bacula Enterprise Only

This solution is only available for Bacula Enterprise. For subscription inquiries, please reach out to sales@baculasystems.com.

This Bacula Systems chapter explains how Bare Metal Recovery of Linux systems can be done with the LinuxBMR toolkit Bacula Systems provides.

Note

The reader of this paper is expected to have a good understanding of Bacula in general, i. e. working with the configuration files and bconsole should be expected. Also, general system administration knowledge as required for the backed up environment is assumed. The terminology used with Bacula needs also to be known.

To make sure you understand the current state of this Bacula Systems LinuxBMR toolkit, please read the Release Notes.

As any component that is to become part of a Disaster Recovery solution, the LinuxBMR toolkit needs to be extensively tested on any hardware it will be used on. Test results, site- or system-specific procedures, and essential configuration should be documented in a Disaster Recovery manual.

Bare Metal Recovery or BMR for short, is the term usually used to describe restoration of a complete operating system to new hardware without actually going through the operating system’s installation procedure.

The main goal is to get from a new, empty machine (bare metal) to a fully functional operating system including all applications and data as quickly as possible. The real challenge is to set up the disk subsystem of the new machine in a way that closely resembles the original disk layout where data was backed up from, and to ensure the recovered operating system can be booted.

If the new hardware is of a different type than the machine the installed software was backed up from originally, BMR will very often not be possible. To be useful, BMR procedures need to take that into account. It is necessary to ensure that the BMR hardware being restored to is compatible with the source system.

In the example in table BMR source and target examples, some common situations for Linux users today are outlined. In particular it is important to understand that software written for 32-bit x86-CPUs can be run on 64-bit x86-CPUs, but not vice versa, and that software written to run on one CPU family, like Sparc or x86, will not run on any other CPU family.

BMR source and target examples
Origin	New Hardware	Problems	BMR possible?
i386	i386	None	Yes
i386_64	i386_64	None	Yes
i386	i386_64	Existing software not optimized for hardware	Yes
i386_64	i386	64-bit software will not run on 32-bit hardware	No
i386	SPARC	Completely different hardware	No