草稿：Linux 将 firewalld 替换 iptables

关闭 firewalld

systemctl stop firewalld
systemctl disable firewalld
systemctl mask --now firewalld

安装iptables

yum install -y iptables-services

启动iptables

systemctl start iptables
systemctl enable iptables

可选操作：

systemctl start ip6tables
systemctl enable ip6tables