Simple firewall with UFW

Block incoming traffic, allow only what is useful.

1. Install UFW if needed:

   sudo apt install ufw

   Copy
2. Default policy:

   sudo ufw default deny incoming
   sudo ufw default allow outgoing

   Copy
3. Allow SSH BEFORE enabling (otherwise you lose access):

   sudo ufw allow ssh

   Copy
4. Allow other services then enable:

   sudo ufw allow 80,443/tcp
   sudo ufw enable

   Copy
5. Check:

   sudo ufw status verbose

   Copy