1.查看防火墙状态
systemctl status firewalld
firewall-cmd --state #查看默认防火墙状态（关闭后显示notrunning，开启后显示running）
2.查看防火墙是否开机启动
systemctl is-enabled firewalld
3.关闭防火墙
systemctl stop firewalld
systemctl stop firewalld.service
systemctl status firewalld
4.禁用防火墙（系统启动时不启动防火墙服务）
systemctl disable firewalld
systemctl disable firewalld.service
systemctl is-enabled firewalld