当我使用dnspython查询权威名称服务器的NS记录时,它会引发NoAnswer异常,尽管我的数据包捕获表明收到了正确的响应.
示例:请求j.gtld-servers.net(192.48.79.30)获取stackoverflow.com的NS记录
>>> import dns.resolver
>>> r = dns.resolver.Resolver()
>>> r.nameservers = ['192.48.79.30']
>>> for answer in r.query('stackoverflow.com', 'NS'):
... print answer.to_text()
...
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/local/lib/python2.7/dist-packages/dns/resolver.py", line 905, in query
raise_on_no_answer)
File "/usr/local/lib/python2.7/dist-packages/dns/resolver.py", line 142, in __init__
raise NoAnswer
dns.resolver.NoAnswer
>>>
Wireshark显示答案确实回来了:
Frame 2: 157 bytes on wire (1256 bits), 157 bytes captured (1256 bits)
Ethernet II, Src: xxxxxxxxxxxxxx (xx:xx:xx:xx:xx:xx), Dst: xxxxxxxxxxxxx (xx:xx:xx:xx:xx:xx)
Internet Protocol Version 4, Src: 192.48.79.30 (192.48.79.30), …