1 停用firewalld
uname -r
3.10.0-514.26.2.el7.x86_64
systemctl stop firewalld.service
systemctl disable firewalld.service

2 安装iptables
yum install iptables iptables-services

3 启用iptables
systemctl start iptables.service
systemctl enable iptables.service

4 保存配置:
service iptables save