systemctl status firewalld

systemctl start firewalld
#如出现错误 Failed to start firewalld.service: Unit is masked. 运行下面
systemctl unmask firewalld

#开80端口命令：
firewall-cmd --zone=public --add-port=80/tcp --permanent

#--zone=public  #作用域
#--add-port=80/tcp  添加80端口，格式：端口/协议
#--permanent   #永久生效，没有重启无效

firewall-cmd --zone=public --remove-port=80/tcp --permanent

firewall-cmd --reload

firewall-cmd --zone=public --list-ports

systemctl enable firewalld.service

systemctl stop firewalld