Linux From Scratch

Linux From Scratch (LFS) is a type of a Linux installation and the name of a book written by Gerard Beekmans among others. The book gives readers instructions on how to build a GNU/Linux system from source. The book is available freely from the Linux From Scratch website and is currently in version 7.2.

Linux From Scratch is a way to install a working Linux system by building all components of it manually. This is, naturally, a longer process than installing a pre-compiled Linux distribution. According to the Linux From Scratch website, the advantages to this method are a compact, flexible and secure system and a greater understanding of the internal workings of the Linux-based operating systems.

To keep LFS small and focused, the book Beyond Linux From Scratch (BLFS) was created which presents instructions on how to further develop the basic Linux system that was created in LFS. It introduces and guides the reader through additions to the system including networking, X, sound, printer and scanner support. Since Release 5.0, the BLFS book version matches the LFS book version.

In addition to the LFS and BLFS books, Cross Linux from Scratch (CLFS) describes cross compiling and Hardened Linux From Scratch (HLFS) focuses on security enhancements like the use of Stack-smashing protection, PaX and Address space layout randomization using grsecurity. Cross Linux from Scratch provides the necessary instructions to build a base, command line only Linux distribution. While LFS is limited to the x86 architecture, CLFS supports a broader range of processors. CLFS addresses advanced techniques not included in the LFS book such as cross-build toolchains, multilibrary support (32 & 64-bit libraries side-by-side), and alternative instruction set architectures such as x86-64, Itanium, SPARC, MIPS, and Alpha. Hardened Linux From Scratch focuses on creating a more secure version of the original Linux From Scratch as its main purpose, including embedded systems.