一、CentOS 7 關閉打開防火牆
1、啓動防火牆: systemctl start firewalld.service
2、禁用防火牆: systemctl stop firewalld.service
3、設置開機啓動: systemctl enable firewalld.service
4、停止並禁用開機啓動: sytemctl disable firewalld.service
5、重啓防火牆: firewall-cmd --reload
6、查看狀態: systemctl status firewalld.service
二、CentOS 6 關閉打開防火牆
1、開啓防火牆(重啓後永久生效):chkconfig iptables on
2、關閉防火牆(重啓後永久生效):chkconfig iptables off
3、開啓防火牆(即時生效,重啓後失效):service iptables start
4、關閉防火牆(即時生效,重啓後失效):service iptables stop
5、重啓防火牆:service iptables restartd