nanog mailing list archives

Re: large organization nameservers sending icmp packets to dns servers.


From: John Levine <johnl () iecc com>
Date: 6 Aug 2007 17:21:49 -0000


Sounds like one of the global-scale load balancers - when you do a
(presumably) recursive DNS lookup of one of their hosts, they'll ping
the nameserver from several locations and see which one gets an
answer the fastest.

Why would they ping rather than just sending the query to all of the
NS and see which one answers first?  It's an IP round trip either way.

I agree that pinging is harmless, but for this application it seems
pointless, too.

R's,
John


Current thread: