惯例是一段废话
前几天开始把各服务器从 Ubuntu 迁移到了 CentOS，然而在配置 iptables 的时候发现表好像不太对劲，Google 后得知原来 CentOS 7 中默认的防火墙从 iptables 换成了 firewalld，然而懒人如我 = = 所以还是先换回 iptables 以当权宜之计
Reverting to the iptables Service
If you are not ready to make the break to firewalld, you can still use the iptables service by issuing the following commands.
systemctl stop firewalld systemctl disable firewalld yum install iptables-services iptables-service touch /etc/sysconfig/iptables systemctl start iptables systemctl enable iptables touch /etc/sysconfig/ip6tables systemctl start ip6tables systemctl enable ip6table
