Did you know? It is always a good idea to save iptables rules before you make changes on Linux:
iptables-save > rules.v4
ip6tables-save > rules.v6
Restore it:
iptables-restore < rules.v4
ip6tables-restore < rules.v6
See https://www.cyberciti.biz/faq/how-to-save-iptables-firewall-rules-permanently-on-linux/ for more info.
