Re: making socket.getaddrinfo use cached dns

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Date	Fri, 8 Jul 2011 04:26:37 +1000
Subject	Re: making socket.getaddrinfo use cached dns
From	Chris Angelico <rosuav@gmail.com>
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On Fri, Jul 8, 2011 at 4:18 AM, high bandwidth <widebandwidth@gmail.com> wrote:
> I use cached dns lookups with pdnsd on my ubuntu machine to speed up web
> access as regular lookups can take 15-30 seconds. However, python's
> mechanize and urllib etc use socket.getaddrinfo, which seems not to be using
> dns cacheing or taking a long time because of ipv6 lookups. In either case,
> I subsequent access to the same site to be fast and not require lengthy
> calls to getaddrinfo. How can I get python to correctly use cached dns
> lookups and ipv4 only (at least in those cases where it is appropriate).

One solution would be to do your own DNS lookups and then pass urllib
an IP address. Is pdnsd set up to be your computer's primary resolver?
(Is /etc/resolv.conf pointing to localhost?) If not, that might help.
I've generally done my DNS caching using BIND, so I can't help with
pdnsd specifically.

ChrisA

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Re: making socket.getaddrinfo use cached dns Chris Angelico <rosuav@gmail.com> - 2011-07-08 04:26 +1000
  Re: making socket.getaddrinfo use cached dns Nobody <nobody@nowhere.com> - 2011-07-08 07:18 +0100

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