large organization nameservers sending icmp packets to dns servers.

John Levine johnl at
Mon Aug 6 17:21:49 UTC 2007

>> 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.


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