| General |
|
|
clear |
clears the terminal |
clear |
echo |
outputs the value of the variable or string |
echo "Hi" >> test.txt |
cd |
enter a directory |
cd .. |
reboot |
reboot the system |
reboot |
exit |
exit the current user or the terminal |
exit |
shutdown |
shutdowns the system |
shutdown -P |
| Info |
|
|
whoami |
print the current user |
whoami |
man |
show the manual of the command (—help) |
man ls |
apropos |
search for the word in the description of all commands |
apropos list |
hostname |
display or set a computer’s hostname |
hostname |
uname |
show all the information of the OS |
uname -a |
nproc |
print the number of processing units available |
nproc |
uptime |
show how long system has been running, number of logged-on users, and system load averages |
uptime |
w or who |
Show who is logged on and what they are doing |
w |
whereis |
locate the binary, source, and manual page files for a command |
whereis command |
which |
locate a command |
which command |
ifconfig or iwconfig |
lists all the network interfaces on your machine |
ifconfig |
netstat |
print network connections, routing tables, interface statistics… |
netstat -an |
lscpu |
list CPU architecture information |
lscpu |
lsusb |
list information about USBs |
lsusb |
lsblk |
list block devices |
lsblk |
lspci |
list PCI devices |
lspci |
lshw |
hardware info |
lshw |
free |
show memory and swap usage |
free |
du |
show directory space usage |
du |
df |
show disk usage |
df -h |
lsmod |
loaded kernel modules |
lsmod |
| Files & Directories |
|
|
mkdir |
makes a folder with the specified name |
mkdir Songs |
rmdir |
removes the specified folder |
rmdir Songs |
touch |
create file or update timestamp of existing |
touch test.txt |
nano |
edit file in nano editor |
nano cmds.txt |
tail |
reads the last 10 lines of the file |
tail cmds.txt |
head |
reads the first 10 lines of the file |
head cmds.txt |
cat |
reads the specified file |
cat cmds.txt |
tac |
reads the specified file in reverse |
tac cmds.txt |
find |
search for files in a directory hierarchy |
find /path/to/search -name "*.txt" |
diff |
compare files line by line |
diff file1.txt file2.txt |
grep |
print lines matching a pattern |
grep "pattern" file.txt |
less |
read file with pagination |
less file.txt |
cp |
copy file or folder |
cp music.mp3 |
mv |
rename or move a file or folder |
mv exe txt |
rm |
remove files or directories |
rm -rf folderWithFilesInside |
ln |
create links |
ln -s target link |
lsof |
list opened files |
lsof |
sed |
stream editor for filtering and transforming text |
sed 's/old/new/g' file.txt |
locate |
find files by name |
locate filename |
wc |
print newline, word, and byte counts for each file |
wc -l -w -c file.txt |
ls |
list all items in the current folder (-I formats) |
ls -lah |
tree |
lists the files in the current directory |
tree |
pwd |
print the name of the current directory |
pwd |
| Compression/Decompression |
|
|
tar |
manipulate archives files (c - create archive, t - table of contents, x - extract, f - use zip/gzip, j - bzip2 compression, v - verbose) |
tar -czvf archive.tar.gz /path/to/source |
zip |
compresses the specified files |
zip files |
unzipzip |
decompress the specified files |
unzip files |
bzip2 |
compress and decompress files with the extension “bz2” |
bzip2 -z cmds |
gzip |
same as bzip2 but compresses files with a gz extension |
gzip file |
| Users |
|
|
users |
shows names of users logged in |
users |
adduser or useradd |
adds another user |
adduser david |
deluser |
deletes a user |
deluser david |
passwd |
change user password |
passwd [user] |
usermod |
modify user settings and preferences |
usermod david --shell /bin/bash |
su |
impersonate as the specified user |
su root |
id |
print user and group information |
id |
| Priviliges/Permission |
|
|
chmod |
change file mode |
chmod +x script.sh |
chown |
change file owner and group |
chown user:group file.txt |
| Networking |
|
|
ping |
ping host |
ping host |
whois |
get whois for domain |
whois domain |
dig |
get DNS for domain |
dig domain |
dig-x |
reserve lookup host |
dig-x host |
| Download/Installation |
|
|
curl |
download a URL |
curl -o https://example.com/file.txt |
wget |
download file |
wget -c file or wget -r url |
dpkg |
install .deb |
dpkg -i file.deb |
alien |
install .rpm |
alien -i file.rpm |
| Remote Connection |
|
|
rsync |
remote file copy |
rsync -avz source/ user@destination:/path/to/destination |
scp |
secure copy (remote file copy program) |
scp file.txt user@remote:/path/to/destination |
ssh |
OpenSSH SSH client (remote login program) |
ssh -p port user@hostname |
| Processes |
|
|
pkill |
kill process based on name and other attributes |
pkill -f process_name |
kill |
kill process with process id (pid) |
kill -9 PID |
killall |
kill processes |
killall |
ps |
display currently active processes |
ps aux |
systemctl |
manage all the background running services (daemons) |
sudo systemctl disable ssh |
journalctl |
see all the logs for systemctl |
journalctl -xe |
pgrep |
look up processes based on name and other attributes |
pgrep -u username process_name |
top or htop |
displays currently-running processes |
top |
| Variables |
|
|
~ or $HOME |
Home |
ls $HOME |
$USER |
current user’s name |
echo $USER |
$PATH |
search paths for binaries |
echo $PATH |
$PWD |
current working directory |
echo $PWD |
| Other |
|
|
visudo |
recommended way to edit /etc/sudoers file |
sudo visudo |
vipw |
recommended way to edit /etc/passwd file |
sudo vipw |