As a tech, you’ll no doubt come in contact with Linux. This post has a few basic Linux commands you should know.
If you want more information on various commands you can enter man <command>.
Basic Usage
| Command |
Function |
Example Usage |
| man |
view manual entry |
man mount |
| ls |
list directory content |
ls /home/user |
| mkdir |
make directory |
mkdir /home/user/new |
| rmdir |
remove directory |
rmdir /home/user/deleteme |
| cd |
change current directory |
cd /home/user/new |
| pwd |
print current directory |
pwd |
| rm |
remove (delete) file |
rm todelete |
| cat |
output file to std out (screen) |
cat /home/user/file.txt |
| grep |
regex search |
grep strtofind /home/user/file.txt (see man page); use grep -i for case insensitive |
| tail |
output last lines of file |
cat /home/user/log.txt | tail |
| more |
by-page view of file |
cat /home/user/log.txt | more |
| dmesg |
prints message buffer of kernel |
dmesg | more |
| top |
display process information |
top |
| mv |
moves the specified files |
mv -i originalfile newfile |
| cp |
copies the specified files |
cp -R sourcedestination |
Basic Diagnostics
| Command |
Function |
Example Usage |
| lspci |
list PCI devices |
lspci -v |
| lsusb |
list USB devices |
lsusb -v |
| df -h |
display free space on disks |
df -h |
| sudo fdisk -l |
list connected devices |
sudo fdisk -l |
| tail -f |
watch a log live |
tail -f /var/log/messages |
Basic Networking and Processing
| Command |
Function |
| ifconfig -a |
show net adapter information |
| ifconfig -a | grep HWaddr |
print MAC addresses |
| ps -A | grep <program name> |
kill processes by name |
| sudo /etc/init.d/networking restart |
restart networking |
| sudo /etc/init.d/gdm restart |
restart graphics system (gnome) |
| sudo dexconf |
reset graphics configuration |
| sudo ufw status |
get firewall status |
| sudo ufw enable |
turn on the firewall |
| ufw allow port |
allow port |
| ufw deny port |
block port |
| sudo apt-get -f install |
try to fix broken packages |
| sudo apt-get upgrade |
upgrade all packages |
