问题
How can I look up a hostname given an IP address? Furthermore, how can I specify a timeout in case no such reverse DNS entry exists? Trying to keep things as fast as possible. Or is there a better way? Thank you!
回答1:
>>> import socket
>>> socket.gethostbyaddr("69.59.196.211")
('stackoverflow.com', ['211.196.59.69.in-addr.arpa'], ['69.59.196.211'])
For implementing the timeout on the function, this stackoverflow thread has answers on that.
回答2:
What you're trying to accomplish is called Reverse DNS lookup.
socket.gethostbyaddr("IP")
# => (hostname, alias-list, IP)
http://docs.python.org/library/socket.html?highlight=gethostbyaddr#socket.gethostbyaddr
However, for the timeout part I have read about people running into problems with this. I would check out PyDNS or this solution for more advanced treatment.
来源：https://stackoverflow.com/questions/2575760/python-lookup-hostname-from-ip-with-1-second-timeout