Configure UFW on Debian 12

UFW (Uncomplicated Firewall) is the default firewall front-end on Debian 12.

Step 1 – Install UFW (if not present)

apt install -y ufw

Step 2 – Default policies

ufw default deny incoming
ufw default allow outgoing

Step 3 – Allow services

ufw allow ssh
ufw allow 80/tcp
ufw allow 443/tcp
ufw allow 8080/tcp

Step 4 – Enable UFW

ufw enable
# Answer 'y' to confirm

Step 5 – Status

ufw status verbose

Step 6 – Allow from specific IP

ufw allow from 192.168.1.100 to any port 3306

Step 7 – Delete a rule

ufw delete allow 8080/tcp

Step 8 – Rate limiting (SSH brute force protection)

ufw limit ssh