Install shorewall by entering the following commands in the terminal:
sudo apt update sudo apt install shorewall
Description:
Shoreline Firewall, netfilter configurator
Shorewall allows firewall/gateway requirements to be described using entries in a set of configuration files. It reads those configuration files and, with the help of the iptables utility, configures netfilter to match these requirements. . Shorewall supports a wide range of router/firewall/gateway applications, traffic shaping and almost every type of VPN.
Homepage: http://www.shorewall.net
Version: 5.1.12.2-1
Section: universe/net