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461

answers:

2

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!

+2  A: 
>>> 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.

ChristopheD
+1  A: 

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.

adamse