Way back in the early days of Linux – and I do mean way back – there were no distributions.  People who wanted to play with Linux had to knit together various packages and tools to make a functional system.

This era didn’t last long.  Within a year there were distributions (such as Slackware) that eliminated a lot of this drudgery and trial-and-error by providing you with package management tools.  These distributions pre-built code, make sure everything was compatible, and provided configurations that worked without you having to read endless reams of documentation and creating your own init system.

The tradeoffs here are obvious: you’re surrendering flexibility for convenience.  For most people, this exchange is a no-brainer.  Sure, the ability to completely customize your system the way you want is cool, but if you just want to get some work done, you probably don’t care how things are laid out in /etc.

But what if you want that complete freedom?  If so, you want Linux From Scratch.

What Is Linux From Scratch?

Linux From Scratch is a project that teaches you how to build a complete Linux system from source code. You begin with an existing Linux system, create a clean build environment, compile a temporary toolchain, enter a chroot, and then build the real system piece by piece.

By the time you are done, you’ll have assembled the familiar guts of Linux yourself:

• binutils
• gcc
• glibc
• Bash
• coreutils
• an init system
• the Linux kernel and bootloader
• filesystem layout
• basic networking
• essential users, groups, logs, and device handling

In other words, you’ll have created your own distro.

The Book

The neat thing about LFS is that there is a step-by-step book that walks you through each stage.  So you don’t have to get the gcc sources and then read through the docs to figure out how to compile the compiler.  LFS does a lot of this heavy lifting for you.

But you’ll still be the one typing the commands and making some decisions.

Will you use it on a LowEnd VPS?  You could – assuming your provider allows a custom ISO.  Are you going to really gain anything practical vs. running Debian?  Probably not.  But you certainly could.

What You Need Before Starting

Linux From Scratch is not beginner Linux. You do not need to be a kernel developer, but you should be comfortable with:

• The command line
• Editing files with a terminal editor (for example, Vim)
• Partitions and filesystems
• Shell scripts
• Compiling software

LFS is not hard because each individual command is mysterious but rather because the process is long and exact.  It’s easy to derail your build, which means figuring out what went wrong, backing up, and redoing things.

My personal advice is to do this on a VM, such as Virtualbox, where you can take snapshots and checkpoint your progress.  That way if you mess things up, you can effortlessly back up to the beginning of the chapter and try again.

The High-Level Build Process

The LFS process goes ike this:

• Prepare your host system.  The book has tools to help with this.
• Create a new partition that will hold your new LFS system
• Build the temporary toolchain – just enough compiler and system tools to build the final system
• Enter chroot (make your new partition “live”)
• Finish building your system
• Configure everything
• Reboot
• Pray!

When it works, it feels terrific.  When it doesn’t…congratulations, you are now learning Linux for real 😄

Should You Try It?

You will definitely learn a lot about how Linux works by building it from nothing.  Will this help you get a got as a Linux sysadmin?  Probably not.  If that’s your goal, go study RHEL.

But if you want a deeper appreciation of what all the piece parts do, then this is an excellent project.  It’s satisfying as a DIYer to point to a VM and say “I built every bit on that”.

You will definitely be a better sysadmin when you’re done.  You’ll also know more about the packages, tools, and choices that go into a distribution.  And if some day you want to build your own distro, this is a great place to start.

raindog308

raindog308 is a longtime community LETizen, technical writer, and self-described techno polymath. With deep roots in the *nix world, he has a passion for systems both modern and vintage, ranging from Unix, Perl, Python, and Golang to shell scripting and mainframe-era operating systems like MVS. He’s equally comfortable with relational database systems, having spent years working with Oracle, PostgreSQL, and MySQL.

As an avid user of LowEndBox providers, raindog308 runs an empire of LEBs, from tiny boxes for VPNs, to mid-sized instances for application hosting, and heavyweight servers for data storage and complex databases. He brings both technical rigor and real-world experience to every piece he writes.

Beyond the command line, raindog308 has a life-long love of German Shepherd Dogs, high-quality knives, target shooting, theology, tabletop RPGs, playing guitar, and hiking in deep, quiet forests.

His goal with every article is to help users, from beginners to seasoned sysadmins, get more value, performance, and enjoyment out of their infrastructure.

You can find him daily in the forums at LowEndTalk under the handle @raindog308.