在搭建dns测试服务器后进行nslookup
ubuntu服务器上测试，提示警告
;; Warning: query response not set
# nslookup x.com 127.0.0.1
Server: 127.0.0.1
Address: 127.0.0.1#53
Non-authoritative answer:
Name: x.com
Address: x.x.x.x
;; Warning: query response not set
原因时 response->qr 设置错误，查询结果应该返回 1