防火墙

systemctl start firewalld # 启动,
systemctl enable firewalld # 开机启动
systemctl stop firewalld # 关闭
systemctl disable firewalld # 取消开机启动

firewall-cmd —permanent —add-port=40000-40080/tcp
firewall-cmd —permanent —add-service=ftp
firewall-cmd —reload
firewall-cmd —zone=public —list-service //查看当前系统防火墙放行的所有服务