ufw無効

1. sudo ufw disable
2. sudo systemctl stop ufw
3. sudo systemctl disable ufw
4. reboot

sudo apt install nftables

sudo update-alternatives --config iptables

• nftablesを選択

sudo vim /etc/nftables.conf

#!/usr/sbin/nft -f
flush ruleset

table inet filter {
  chain input {
	type filter hook input priority 0; policy drop;

	iifname "lo" counter accept

	ct state established,related counter accept

	ct state new tcp dport 22 counter accept
  }

  chain forward {
	type filter hook forward priority 0; policy drop;
  }

  chain output {
	type filter hook output priority 0; policy accept;
  }
}

起動と有効化

• systemctl enable nftables --now

動作確認

• nft list ruleset
• sudo iptables --version
  • iptables v1.8.4 (nf_tables)