问题现象：
搭建了DNS服务器后，访问被拒绝
[root@localhost opt]# nslookup www.wangzy.com ;; Got SERVFAIL reply from 192.168.43.12, trying next server ;; connection timed out; trying next origin ;; Got SERVFAIL reply from 192.168.43.12, trying next server ;; connection timed out; no servers could be reached
原因：书写数据配置文件时，默认给与的配置文件权限不对
解决办法：
添加对应权限，重启服务器
再次访问成功：
