Install and configure UFW (Uncomplicated Firewall) on Ubuntu 18.04

ufw-install-config.sh

sudo apt install ufw -y
sudo ufw enable

# sudo ufw default deny
sudo ufw default deny incoming
sudo ufw default allow outgoing

# Allow common apps
sudo ufw allow ssh
sudo ufw allow Samba
sudo ufw allow http
sudo ufw allow https

# Deny specific IP
# sudo ufw deny from 0.0.0.0

# Check status
sudo ufw status verbose

# Start & Stop
# service ufw start
# service ufw stop