Linux Cookbook

Chapter 9. Managing Files and Partitions

Introduction

Understanding filesystem fundamentals is key to understanding how Linux works. Everything is a file—data files, partitions, pipes, sockets, and hardware devices. Directories are simply files that list other files.

The Filesystem Hierarchy Standard (FHS) was developed as a voluntary standard. Most Linuxes follow it. These are the required elements of the Linux root filesystem:

/

Root directory, even though it is always represented at the top

/bin

Essential system commands

/boot

Static boot loader files

/dev

Device files

/etc

Host-specific system configuration files

/lib

Shared libraries needed to run the local system

/mnt

Temporary mount points

/opt

Add-on software packages (not used much in Linux)

/proc

Live kernel snapshot and configuration

/sbin

System administration commands

/tmp

Temporary files—a well-behaved system flushes them between startups

/usr

Shareable, read-only data and binaries

/var

Variably sized files, such as mail spools and logs

These are considered optional because they can be located anywhere on a network, whereas the required directories must be present to run the machine:

/home

User’s personal files

/root

Superuser’s personal files

The FHS goes into great detail on each directory, for those who are interested. Here are some things for the Linux user to keep in mind:

• /tmp and /var can go in their own individual partitions, as a security measure. If something goes awry and causes them to fill up uncontrollably, they will be isolated from ...