centos 7+防火墙命令

#开启3306端口
firewall-cmd --zone=public --add-port=3306/tcp --permanent
#重新加载策略
firewall-cmd --reload
#关闭防火墙
systemctl stop firewalld
#开启防火墙
systemctl start  firewalld
#开机是否启动
systemctl disable | enable firewalld