http://privex3guvvasyer6pxz2fqcgy56auvw5egkir6ykwpptferdcb5toad.onion/articles/setting-up-a-firewall-linux
You'll also want to whitelist traffic to the interface lo (loopback), which is internal network traffic such as to 127.0.0.1 / ::1 You may also want to whitelist ICMP, so that you can still ping / traceroute your server The following rules do all of the above, for both IPv4 and IPv6: iptables -I INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -I INPUT -p icmp -j ACCEPT
iptables -I INPUT -i lo -j ACCEPT
ip6tables -I INPUT -m state --state ESTABLISHED,RELATED -j...