Linux Professional Institute LPIC-1 Exam 101
Devices Linux Filesystems Filesystem Hierarchy Standard
Find System Files and Place Files in the Correct Location Part 1 FHS
Introduction
The Filesystem Hierarchy Standard (FHS) defines a common directory layout and its contents for Unix-like operating systems. Maintained by the Linux Foundation and detailed in the FHS 3.0 specification, this standard ensures that users and administrators can predict where to find system files, binaries, and configuration data. While FHS compliance is not mandatory, most Linux distributions follow it closely.
Note
FHS compliance guarantees a consistent directory layout, simplifying system administration, backups, and package management.
Top-Level Directory Overview
| Path | Purpose | Common Contents / Examples |
|---|---|---|
/ | Root of the filesystem hierarchy | Everything lives under / |
/bin | Essential command binaries available to all users | ls, cp, mv |
/boot | Static files for the bootloader | Kernel images (vmlinuz), initrd |
/dev | Device nodes for hardware & virtual devices | /dev/sda, /dev/null |
/etc | Host-specific configuration files | fstab, hosts, service configs |
/home | User home directories | /home/alice, /home/bob |
/lib | Shared libraries needed by /bin and /sbin | libc.so.6, kernel modules |
/media | Mount points for removable media (USB, CD/DVD) | /media/usb, /media/cdrom |
/mnt | Temporary mount points for administrators | /mnt/shared |
/opt | Optional or third-party software packages | /opt/google, /opt/mysql |
/root | Superuser’s home directory | /root/.bashrc, /root/.ssh/ |
/run | Runtime data (PID files, sockets) | /run/docker, /run/sshd.pid |
/sbin | System binaries for booting & maintenance | fsck, ip, iptables |
/srv | Data served by system services | /srv/www/, /srv/ftp/ |
/tmp | Temporary files cleared at reboot | /tmp/session_12345 |
/usr | Secondary hierarchy for read-only user applications | /usr/bin, /usr/lib, /usr/share |
/proc | Virtual filesystem for process & kernel information | /proc/cpuinfo, /proc/<pid>/ |
/var | Variable data files (logs, spools, caches) | /var/log, /var/spool/mail |
/var/tmp | Temporary files preserved between reboots | /var/tmp/install_cache |
Summary Tree
/
├── bin
├── boot
├── dev
├── etc
├── home
├── lib
├── media
├── mnt
├── opt
├── root
├── run
├── sbin
├── srv
├── tmp
├── usr
├── proc
└── var
└── tmp
Further Reading
- Filesystem Hierarchy Standard (FHS 3.0)
- Linux Directory Structure Explained
- The Linux Documentation Project
Ready to test your understanding? Proceed to the quiz section!
Watch Video
Watch video content