查看防火墙状态 ``` sudo systemctl status firewalld ``` 启动防火墙 ``` sudo systemctl start firewalld ``` 停止防火墙 ``` sudo systemctl stop firewalld ``` 查看防火墙已经开放的端口 ``` firewall-cmd --list-port ``` 添加开放指定端口 ``` firewall-cmd --zone=public --add-port=需要开启的端口号/tcp --permanent ``` 设置完成后要重新加载防火墙 ``` firewall-cmd --reload ```