## 🐧 Linux Command Cheatsheet
## 📁 File and Directory Management
| Command | Description |
|---|---|
ls |
List files in current directory |
ls -la |
List all files with details (including hidden) |
cd /path/to/directory |
Change directory |
pwd |
Print current working directory |
mkdir dirname |
Create new directory |
mkdir -p parent/child |
Create nested directories |
rm file |
Remove file |
rm -r directory |
Remove directory recursively |
rm -f file |
Force remove file without prompt |
cp source dest |
Copy file or directory |
cp -r source dest |
Copy directory recursively |
mv source dest |
Move or rename file/directory |
touch filename |
Create empty file or update timestamp |
cat file |
Display file contents |
head -n 10 file |
Show first 10 lines |
tail -n 10 file |
Show last 10 lines |
tail -f file |
Follow file for live updates |
find /path -name file |
Search for files by name |
file filename |
Show file type |
## 🛠️ File Permissions and Ownership
| Command | Description |
|---|---|
ls -l |
Show detailed file info |
chmod 755 file |
Change file permissions (rwxr-xr-x) |
chmod u+rwx file |
Add read, write, execute permissions to user |
chmod -R 644 /path/dir |
Apply permissions recursively |
chown user:group file |
Change file owner and group |
chown -R user:group /path |
Change ownership recursively |
stat file |
Show detailed file metadata |
## 🖥️ Process Management
| Command | Description |
|---|---|
ps aux |
Show all running processes |
ps -ef |
Show detailed process list |
top |
Interactive process viewer |
htop |
Enhanced interactive process viewer |
kill PID |
Terminate process by PID |
kill -9 PID |
Force kill process |
pkill processname |
Kill processes by name |
killall processname |
Kill all instances of a process |
nice -n 10 command |
Run command with adjusted priority |
jobs |
List background jobs |
fg %1 |
Bring job #1 to foreground |
bg %1 |
Resume job #1 in background |
## 📡 Networking
| Command | Description |
|---|---|
ip a |
Show network interfaces and IPs |
ifconfig |
Show network interfaces (legacy) |
ping example.com |
Ping a host |
traceroute example.com |
Trace network route |
netstat -tuln |
List listening ports |
ss -tuln |
Show socket statistics (modern) |
curl http://example.com |
Fetch URL content |
wget http://example.com/file |
Download files |
dig example.com |
DNS lookup |
nslookup example.com |
DNS lookup |
tcpdump -i eth0 |
Capture network packets |
scp file user@host:/path |
Secure copy file to remote host |
ssh user@hostname |
Connect to remote host via SSH |
## 📦 Package Management
| Distro | Command Example | Description |
|---|---|---|
| Debian/Ubuntu | sudo apt update && sudo apt upgrade |
Update packages |
sudo apt install package |
Install package | |
sudo apt remove package |
Remove package | |
| RedHat/CentOS/Fedora | sudo yum update |
Update packages |
sudo yum install package |
Install package | |
sudo yum remove package |
Remove package | |
sudo dnf install package |
Install package (modern RedHat) | |
| Arch Linux | sudo pacman -Syu |
Update system |
sudo pacman -S package |
Install package |
## 📂 Disk Usage and Storage
| Command | Description |
|---|---|
df -h |
Show disk space usage |
du -sh /path |
Show directory size |
mount |
Show mounted filesystems |
umount /dev/sdX |
Unmount filesystem |
lsblk |
List block devices |
## 🧰 System Information
| Command | Description |
|---|---|
uname -a |
Kernel and system info |
cat /etc/os-release |
OS version details |
hostname |
Show hostname |
uptime |
Show system uptime |
free -h |
Show memory usage |
vmstat |
Show virtual memory stats |
dmesg |
Show kernel logs |
whoami |
Show current user |
lscpu |
CPU information |
lshw |
List hardware |
lsblk |
List block devices |
## 📝 Text Processing
| Command | Description |
|---|---|
grep "pattern" file |
Search for text pattern |
grep -r "pattern" /path |
Recursive search |
sed 's/old/new/g' file |
Replace text |
awk '{print $1}' file |
Print first column |
cut -d',' -f1 file |
Cut fields by delimiter |
sort file |
Sort lines |
uniq file |
Remove duplicate lines |
wc -l file |
Count lines |
## 🔒 User Management and Permissions
| Command | Description |
|---|---|
sudo adduser username |
Add new user |
sudo deluser username |
Delete user |
passwd username |
Change user password |
usermod -aG group user |
Add user to group |
groups username |
Show groups user belongs to |
sudo -i |
Switch to root |
su - username |
Switch to another user |
sudo command |
Run command as root |
## ⚙️ Systemctl & Service Management
| Command | Description |
|---|---|
systemctl status service |
Show status of service |
systemctl start service |
Start service |
systemctl stop service |
Stop service |
systemctl restart service |
Restart service |
systemctl enable service |
Enable service on boot |
systemctl disable service |
Disable service on boot |
journalctl -u service |
View service logs |