檢查iptables 狀態
systemctl status firewalld

手動關閉 iptables
systemctl stop firewalld

手動啟動 iptables
systemctl start firewalld

重開機後不執行iptables
手動啟動 iptables
systemctl disable firewalld

重開機後自動執行iptables
手動啟動 iptables
systemctl enable firewalld