[ILUG] Slow DNS resolution on Linux clients
proinnsias at linux.ie
Sat Sep 3 21:24:13 IST 2005
On Sat, Sep 03, 2005 at 03:34:20PM +0100, Robert Sweetnam wrote:
> Hello all,
> DNS configuration is the same for both the Windows and Linux machines with
> IP addresses being assigned from a DHCP server.
> Any ideas?
Yes, a few ...
The most obvious suggestion is that Linux is trying to "do the right
thing (TM)" and attempting to use IPv6 first to do DNS lookups, and only
when this fails is it doing the DNS lookups using IPv4. This is the most
probable cause of the delay and is reasonably easy to solve.
a) Disable IPv6 - there are plenty of arguments for/against
this. Many more qualified than I can give an opinion on it !
b) Configure your network to be IPv6 aware - this might actually
have other advantages too (www.sixxs.net)
c) Configure your resolver to prioritise IPv4 over IPv6
Instructions for doing any of the above are readily available for the
correct fee of a few hundred thousand electrons sent the way of
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