Linux Filesystem Layout

The contents of this page have primarily been adapted from the Filesystem Hierarchy Standard. It briefly summarizes key concepts and material that is necessary to understand when administrating Linux systems which fully (or even partially) adhere to the FHS standard.

Partitioning

The FHS recommends that the root partition be kept as small as possible in order to:

1. Allow mounting it from small media
2. Separating specific system files (i.e. kernel) from more sharable files
3. To not assume that other individuals have large root partitions
4. To reduce the surface area of disk errors impacting the root partition

Structure

The follow directories (or symlinks) are required:

Directory	Description	Link
bin	Essential command binaries	Link
boot	Static files of the boot loader	Link
dev	Device files	Link
etc	Host-specific system configuration	Link
lib	Essential shared libraries and kernel modules	Link
media	Mount point for removable media	Link
mnt	Mount point for mounting a filesystem temporarily	Link
opt	Add-on application software packages	Link
run	Data relevant to running processes	Link
sbin	Essential system binaries	Link
srv	Data for services provided by the system	Link
tmp	Temporary files	Link
usr	Secondary hierachy	Link
var	Variable data	Link

The following directories (or symlinks) are optional:

Directory	Description	Link
home	User home directories	Link
root	Home directory for the root user	Link

In particular, there's a growing convention for using the XDG Base Directory Specification for creating the home directory layout. See the specification here.