Linux Commands (Case Sensitive):
Basic:
pwd ==> print the name of current directory || Ex: pwd
whoami ==> print the current user || Ex: whoami
cd [directoryName] ==> enter a directory || Ex: cd Music
cd .. ==> go back to the parent directory || Ex: cd ..
cp [file] ==> copy file || Ex: cp music.mp3
ls ==> list all items in the current folder || Ex: ls
clear ==> clears the terminal || Ex: clear
mkdir [foldername] ==> makes folder with the specified name || Ex: mkdir Songs
rmdir [foldername] ==> removes the specified folder || Ex: rmdir Songs
echo [param] ==> outputs the value of the variable || Ex: echo "Hi"
or string to stdout
tree ==> lists the files in the current || Ex: tree
directory in tree like format
For sorting files:
mv [file] [newname]==> rename a file or folder || Ex: mv exe txt
cat [filename] ==> reads the specified file || Ex: cat cmds.txt
tac [filename] ==> reads the specified file in reverse || Ex: tac cmds.txt
tail [file, file] ==> reads first 10 lines of the files || Ex: tail cmds.txt
zip [file, file] ==> compresses the specified files || Ex: zip files
vi [file] ==> edit file in the terminal || Ex: vi cmds.txt
gedit [file] ==> edits the file in text editor || Ex: gedit cm.txt
nano [file] ==> edit file in nano editor || Ex: nano cmds.txt
tar ==> same as bzip2 || Ex: tar file
bzip2 -z / -d ==> compress and decompress files with || Ex: bzip2 -z cmds
the extension "bz2" respectively
gzip ==> same as bzip2 but compresses files || Ex: gzip file
with a gz extension.
Getting help:
man [command] ==> show the manual of the command || Ex: ls man
[command] --help ==> similar to man but ouputs in terminal || Ex: pwd --help
apropos [word] ==> search for the word in description || Ex: aprpos list
of all commands
More advanced:
reboot ==> reboot the system || Ex: reboot
which [command] ==> ouputs the location of the command || Ex: which ls
su [username] ==> impersonate as the specified user || Ex: su root
id ==> print user and group information || Ex: id
hostname ==> display or seta computer`s hostname || Ex: hostname
uname -a ==> show all the information of the OS || Ex: uname -a
exit ==> exit the current user or the terminal || Ex: exit
shutdown -P +min ==> shutdowns the system || Ex: shutdown -P
Networking:
ifconfig ==> lists all the network interfaces on || Ex: ifconfig
your machine
netstat ==> displays network connections for TCP, || Ex: netstat
routing tables, and a number of
network interface and network
protocol statistic
For listing hardware:
lscpu ==> list CPU architecture information || Ex: lscpu
lsusb ==> list information about usbs || Ex: lsusb
lsblk ==> list block devices || Ex: lsblk
lsof ==> list opened files || Ex: lsof
lspci ==> list PCI devices || Ex: lscpi
System Administration:
User Management:
who ==> prints the current logged in users || Ex: who
users ==> shows names of users logged in || Ex: users
adduser [username] ==> adds another user || Ex: adduser david
useradd [username] ==> same as adduser but is not preferrd || Ex: useradd david
deluser ==> deletes a user || Ex: deluser david
usermod [user] ==> modify user settings & prefrences || Ex: usermod david --shell /bin/bash
passwd [user] ==> change the password of the user || Ex: passwd
uptime ==> shows how long the system has been || Ex: uptime
running, number logged on users and
the system load averages
visudo ==> recommended way to edit || Ex: sudo visudo
/etc/sudoers file
vipw ==> recommended way to edit /etc/passwd || Ex: sudo vipw
file
systemctl ==> mangae all the background running || Ex: sudo systemctl disable ssh
services (daemons)
journalctl ==> see all the logs for systemctl || journalctl -xe
Important Files:
/etc/passwd ==> stores information of all the users || cat /etc/passwd
/etc/shadow ==> stores the hashed version of every || cat /etc/passwd
user`s password
ps(Process Status)==> displays currently-running processes || Ex: ps
ss(Socket Status) ==> used to dump socket statistics and || Ex: ss
displays information
username ec2-user
sudo su
yum install httpd
service start httpd
chkconfig httpd onif `ls -la`.ok {
echo("hello world")
}
`sleep 10 &`
echo("This will be printed right away!")