添加xxxx/24到80端口白名单：
firewall-cmd --permanent --add-rich-rule=‘rule family="ipv4" source address="x.x.x.x/24" port port="80" protocol="tcp" accept‘
firewall-cmd --complete-reload
firewall-cmd --list-all
原文：http://www.cnblogs.com/flasheryu/p/5892075.html