[smokeping-users] EchopingDNS latencies are 1, 000 times too small.

[Niko Tyni]

On Sat, May 09, 2015 at 03:46:02PM -0700, Malcolm Baldy wrote:
> Ubuntu 14.04.2 LTS x86_64, kept current, but using a hand-rolled Grsecurity
> kernel.

> ++ GoogleDNS
> title = Google DNS
> probe = EchoPingDNS
> dns_request = www.bigpond.com.au
> host = 8.8.8.8
> 
> Reported latency is always about 500-600 microseconds, which seems impossible
> given that my latency to my immediate uplink peer is higher than that.

Looks like the echoping_dns module is buggy and ignores the hostname
argument, querying whatever server is in /etc/resolv.conf instead.

So you're probably seeing the latency of your local caching name server.

 https://bugs.debian.org/588261
 http://sourceforge.net/p/echoping/bugs/52/

-- 
Niko Tyni   ntyni at debian.org