iptables/ip6tables — administration tool for IPv4/IPv6 packet filtering and NAT

Display current rules:

iptables -L
iptables -t nat -L

-n, –numeric
-L, –list

iptables --line-numbers -n -L FORWARD
iptables -I INPUT 9 -s 10.100.100.4/32 -j admin-ips
iptables -I FORWARD 10 -s 10.100.100.37/32 -j ACCEPT
iptables -D FORWARD -s 10.100.100.37/32 -j ACCEPT
iptables -D INPUT 26