Linux Directory Structure Overview
Posted by Admin on March 23rd, 2008
Introduction
In Windows, you use this format to access a directory
D:\Folder\subfolder\file.txt
In Linux, this is the basic format
/Folder/subfolder/file.txt
You’ll notice that the slashes are forward slashes in Linux versus backslashes in Windows. Also, there is no drive name (C:, D:, etc.) in Linux. At boot, the ‘root partition’ is mounted at /. All files, folders, devices and drives are mounted under /. Though it is not apparent from this example, it is important to note that files and folders in Linux are case sensitive.
/Folder/subfolder/file.txt is not the same as /folder/subfolder/file.txt.
Linux Directory Structure Overview
The Directory Structure in Unix & Linux are a unified Directory Structure where in all the directories are unified under the “/” Root file system. Irrespective of where the File System is physically mounted all the directories are arranged hierarchically under the Root file system.
The Linux Directory Structure follows the “Filesystem Hierarchy Structure (FHS)” maintained by the Free Standards Group although most of the distributions sometimes tend to deviate from the standards.
Lets have a quick stroll across the different directories under the Linux Filesystem Hierarchy
“/” Root
The Directory Structure starts with the Root file system “/” and is indeed the root directory for the whole structure.The partition where / (the root directory) will be located on a UNIX or UNIX-compatible system.
/boot
The /boot directory contains the Boot loader files including Grub or Lilo, the Kernel, initrd and system.map config files
/sys
This contains the Kernel, Firmware and system related files.
/sbin
Contains the essential System Binaries and System Administration tools essential for the system operation and performance
/bin
Contains the essential binaries for users and those utilities that are required in single user mode. Examples, include cat, ls, cp etc.
/lib
Contains the library files for all the binaries held in the /sbin & /bin directories
/dev
The /dev directory contains the essential system files and drivers.
/etc
The /etc/directory contain essential System configuration files including /etc/hosts, /etc/resolv.conf, nsswitch.conf, defaults and network configuration files. These are mostly host specific system and application configuration files.
/home
All the user home directories are held under this directory with the exception of the root home directory which is kept under /root directory. This directory holds users files, personal settings like .profile etc.
/media
A generic mount point for removable media like CD-ROM, USB, Floppies etc
/mnt
A generic mount point for temporary file systems. This comes handy particulary when troubleshooting from CDROM etc wherein you might have to mount the Root file system and edit configurations.
/opt
A rarely used directory in Linux for Optional Software Packages. This is extensively used in UNIX OS like Sun Solaris where the software packages are installed
/usr
A sub hierarchy to the root file system which is a User data directory. Contains user specific utilities and applications. You will again see a lot of important but not critical file systems are mounted. Here you would again find a bin, sbin & lib directory which contains non-critical user and system binaries and related libraries and a share directory. Also found here are the include directory with include files
/usr/sbin
Contains Non-essential Non-critical system binaries and network utilities
/usr/bin
Contains Non-Essential Non-critical command binaries for users.
/usr/lib
Library files for the binaries in /usr/bin & /usr/sbin directory.
/usr/share
A platform-independent shared data directory
/usr/local
A sub hierarchy under the /usr directory which has Local System specific data including user and system binaries and their libraries
/var
The /var directory is mostly mounted as a separate filesystem under the root where in all the variable content like logs, spool files for printers, crontab,at jobs, mail, running process, lock files etc. Care has to be taken in planning this file system and maintenance as this can fill up pretty quickly and when the FileSystem is full can cause system and application operational issues.
/tmp
A temporary file system which hold temporary files which are cleared at system reboot. There is also a /var/tmp directory which holds temporary files too. the only difference between the two is that /var/tmp directory holds files that are protected at system reboot. In other words, /var/tmp files are not flushed upon a reboot.
Then you have the virtual (psuedo) file system /proc which resides in the memory and is mounted under the Root holding kernel and process stats in text file formats.
Linux Directory Structure in Visual View
Note:-
This structure could vary from distro to distro and this is a very generic linux directory structure.The directory structure in Linux can be confusing for new users of Linux. Most distributions have the same general structure of the base directory system.
March 28th, 2008 at 2:46 pm
The wording of the this piece is not good — extensive editing is in order.
In particular, the descriptions of /dev and /sys are downright misleading. /dev contains device nodes, not device drivers (which may be linked into the kernel image or reside in separate files under /lib/modules). /sys contains machine-readable textual descriptions or kernel objects, such as modules, devices, buses etc.
April 2nd, 2008 at 4:39 pm
GNU/Linux is not case sensitive; some filesystems it supports are. You can install GNU/Linux on a FAT32 partition, and it won’t have any case sensitivity.
July 10th, 2008 at 2:45 pm
I agree the descriptions of dev and sys are atrocious; it’s a nice newbie explanation tho (nice diagram too;) Yes it should be corrected.
“Also found here are the include directory with include files” er whut?
“A temporary file system which hold temporary files” hmm.
October 20th, 2008 at 7:00 am
Very Good tutorials for new user.
October 28th, 2008 at 4:48 am
Hi guys,
I want create partions for each director.I know that 100Mb more than enough to /boot directory. Anyone has idea about how much space distribute for each directory in the file hierarchy.
February 5th, 2009 at 4:13 pm
Very informative article, which I found quite useful. Cheers ,Jay
May 27th, 2009 at 2:03 pm
Awesome
that is really helpfull for users , who are working on linux
but don’t know basics of linux
July 10th, 2009 at 2:11 pm
It helped me
July 14th, 2009 at 8:38 am
A nice article.
September 2nd, 2009 at 5:37 am
Hi all,
I’m new comer in linux
It useful my further knowledge……
Thanx to all
pasindu
September 22nd, 2009 at 8:38 am
any chance the directories could be called something meaningful like binaries or programs, settings, etc? Or does the kernel have a limited vocabulary?
January 19th, 2010 at 6:56 am
I have installed a “Ubuntu” desktop, and I am unabe to connect via ssh remotely.
Pls help
adventuror@gmail.com
January 19th, 2010 at 10:18 am
Can you check for the ssh daemon, if not running kindly install ssh and check it should be working.
I guess your problem is sorted.
Regards
Selvam Porko
April 23rd, 2010 at 9:27 am
hi
in the /usr there is another subfolder called etc and include and src are there
and again in include there is sys folder is present
u had not specified that sub folders
please check and correct that
b ye
May 2nd, 2010 at 4:16 pm
I agree with one other poster about the directory naming in linux. Whoever thought of that directory naming convention should be punched in the nuts hard and often!
I think this was a decent primer for us new people. Something like this really needs to be done in much more depth though, but it’s good nonetheless.
Ever notice how the “beginning linux” book never cover filename and directory conventions and structure? Drives me nuts. They all pretty much just dive in without that. I had to search a lot of resource3s to find out that executable files weren’t designated by extension, but rather an attribute flag @_@
Can’t wait to get a LAMP system setup to host a site from home =P