iptables

server@coffee:~$ sudo iptables -L
[sudo] password for server:
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

Chain ufw-after-forward (0 references)
target     prot opt source               destination

Chain ufw-after-input (0 references)
target     prot opt source               destination

Chain ufw-after-logging-forward (0 references)
target     prot opt source               destination

Chain ufw-after-logging-input (0 references)
target     prot opt source               destination

Chain ufw-after-logging-output (0 references)
target     prot opt source               destination

Chain ufw-after-output (0 references)
target     prot opt source               destination

Chain ufw-before-forward (0 references)
target     prot opt source               destination

Chain ufw-before-input (0 references)
target     prot opt source               destination

Chain ufw-before-logging-forward (0 references)
target     prot opt source               destination

Chain ufw-before-logging-input (0 references)
target     prot opt source               destination

Chain ufw-before-logging-output (0 references)
target     prot opt source               destination

Chain ufw-before-output (0 references)
target     prot opt source               destination

Chain ufw-reject-forward (0 references)
target     prot opt source               destination

Chain ufw-reject-input (0 references)
target     prot opt source               destination

Chain ufw-reject-output (0 references)
target     prot opt source               destination

Chain ufw-track-input (0 references)
target     prot opt source               destination

Chain ufw-track-output (0 references)
target     prot opt source               destination
server@coffee:~$