Introduction
What is Linux?
Linus himself has said:
- “Linux is just a kernel, and it only gets interesting when paired with all the userland stuff.” (Source: Linus Torvalds, Linux Kernel Mailing List archives)
Meaning: System administration is not just about the kernel but also about managing the surrounding ecosystem (userspace tools, configs, networking, etc.).
Reference:
- Linus Torvalds, Just for Fun: The Story of an Accidental Revolutionary (book, 2001). → In this book he explains his motivation for Linux and the role sysadmins had in early adoption.
Linux Distributions Overview
Linus often emphasizes that he doesn’t control distributions:
- “I don’t make Linux distributions, I just release the kernel. Distributors make the decisions about userland.” (Source: Linus Torvalds, Linux Foundation events Q&A)
This is important for your docs: system administration is tied to distribution-specific tools, but the kernel is common.
Reference:
- Linux Kernel Mailing List (LKML) – Linus repeatedly reminds people: “I only care about the kernel.”
- Talk at Google: “Linus Torvalds on Git” (2007) – he explains why distros exist and why kernel development is separate.
Understanding the Linux Filesystem Hierarchy
Linus did not personally design the Filesystem Hierarchy Standard (FHS). That came later, from the Linux Foundation and other groups. But, he did set early conventions in the Linux kernel source tree and with Minix/Linux in the early 1990s:
- In early releases (Linux 0.01), Linus used a simplified UNIX filesystem layout:
/bin,/usr,/etc,/tmp, etc., inspired by Minix. - His philosophy: “Don’t break userspace.” Meaning once conventions are set (like
/etcfor configs), they must stay stable.
Authentic references from Linus:
- Linux 0.01 source code release (1991) — the earliest filesystem layout can be studied here.
- Linux Kernel Archives: kernel.org — primary source for everything Linus approves.