1. 查看防火牆狀態
systemctl status firewalld.service
2. 關閉防火牆
systemctl stop firewalld.service
3.禁止防火牆開機啓動
systemctl disable firewalld.service
4. 重啓防火牆使配置生效
systemctl restart firewalld.service
5. 設置防火牆開機啓動
systemctl enable firewalld.service
注：CentOS默認使用的防火牆是firewalld,如果要安裝iptables防火牆，則運行 yum -y install iptables-services
