Linux directory structure and details

Linux common directory structure of Centos/Ubuntu

Use of directory’s

• /bin     

1. contains user(Essential) command binaries (executable file)

2. Examples: /bin/top,/bin/mv,/bin/cut,/bin/cp,/bin/rename,/bin/mkdir,etc…

• /boot

1. contains  boot related file

2. Examples: grup, boot loader,kernel

• /dev   

1. contains internal attached device  details

2. Examples: /dev/sda,/dev/sdb,/dev/sdc,/dev/cdrom

• /etc 

1. contains configuration related files

2. Examples: httpd.conf,hosts,reslov.conf,smb.conf,etc….

• /home

1. contains all users home directories

2. Examples: /home/secureethics,/home/bala

• /lib

1. contains 32 bit Libraries for the binaries

• /lib64 

1. contains 64 bit Libraries for the binaries

• /media

1. Used for mount point of removable media

2. Examples: CD-ROM, Pendrive

• /mnt 

1. Used for temporary mounting point

2. Example: NFS,SMB,etc

• /opt

1. Used for third party application installations

• /proc –

1. contains  running process information

2. Examples: /proc/meminfo,/proc/mdstat,/proc/cpuinfo,etc…

• /root –

1. root user(super user) home directory

                   2. Examples: /root/

• /run

1. used for stored the run time  application/service files(It will store file temporary )

• /sbin

1. contains system command binaries (executable file)

2. Examples: /sbin/service,/sbin/sshd,/sbin/smbd.

• /srv

1. Contains server specific services related data.

                   2. Example: /srv/cvs

• /sys

1.contains device drivers,firmware

                   2. Examples: /sys/drivers,/sys/firmware,/sys/bus

• /var 

1. var stands for variable files.

2. Content of the files that are expected to grow can be found under this directory.

3. This includes — system log files (/var/log); packages and database files (/var/lib); emails (/var/mail); print queues (/var/spool); lock files (/var/lock); temp files needed across reboots (/var/tmp);

• /tmp 

1. Directory that contains temporary files created by system and users.

2. Files under this directory are deleted when system is rebooted.

•  /usr

1. Contains binaries, libraries, documentation, and source-code for second level programs.

2. /usr/bin contains binary files for user programs. If you can’t find a user binary under /bin, look under /usr/bin. For example: at, awk, cc, less, scp

3. /usr/sbin contains binary files for system administrators. If you can’t find a system binary under /sbin, look under /usr/sbin. For example: atd, cron, 3. sshd, useradd, userdel

4. /usr/lib contains libraries for /usr/bin and /usr/sbin

5. /usr/local contains users programs that you install from source. For example, when you install apache from source, it goes under /usr/local/apache2