A Netfilter configuration setup script template

1. Review and edit the scripts
2. Run as root. Configure only one per OS because these scripts write to /etc/nftables.conf
3. Make sure iptables is disabled, stopped, and flushed.

systemctl disable --now iptables
iptables --flush

4. Make sure nftables is enabled and restart it.

systemctl enable nftables
systemctl restart nftables

5. Confirm that the ruleset is active with nft list ruleset