ufw
UFW (Uncomplicated Firewall) is the default firewall configuration tool for Ubuntu. It provides a user-friendly interface for managing iptables
rules, making it easy to secure a server. It’s particularly well-suited for host-based firewalls.
For more information, you can refer to the official documentation.
Helpful ufw CMDs and Info
Example of adding an allow rule (NOTE: the inclusion of the protocol at the end for your port)
sudo ufw allow from 127.0.0.1 to any port 80 proto tcp
Delete a specific rule
sudo ufw delete deny 80/tcp
Show all ufw rules and assign a numeric value to each rule
sudo ufw status numbered
Delete a rule by number (from the previous command output)
sudo ufw delete 4
Reload ufw after adding/deleting any rules
sudo ufw reload
Allow from any to a specific port (for testing only) EX:
sudo ufw allow from any to any port 80 proto tcp