nanog mailing list archives

Re: dns based loadbalancing/failover


From: "E.B. Dreger" <eddy+public+spam () noc everquick net>
Date: Sun, 7 Oct 2001 15:51:27 +0000 (GMT)


Date: Sat, 6 Oct 2001 19:17:39 +0200
From: bert hubert <ahu () ds9a nl>

[ snip ]

It gets even better - recursing nameservers have the habit of
locking in to nameservers that respond quickest. So you even
get some loadbalancing awareness.

Odd.  I've investigated this effect (well aware of it in theory)
with stateside-only machines, and DNS frequently returns a
horrible choice.  Maybe caching prevents enough authoritative
answers from being returned to cancel out the noise, but I've
seen the opposite of what you report.

We operate nameservers in the US and in Europe, and we
definitely see this effect.

Maybe it works well over different continents, but simple "use
different IPs from different NS" has not given desirable results
in my experience.

Then we have the failover and TTL issues...


Eddy

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Date: Mon, 21 May 2001 11:23:58 +0000 (GMT)
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