2017-11-23 9:56 GMT+01:00 Michael Meier <michael.meier@fau.de>:
Those times are reproducible, a machine will always get the same 15 or 10 or 4 ms ping. So their anycasted 9.9.9.9 seems to internally redirect queries based on source-IP-hash, and if you're unlucky, they redirect you to a server at the other end of the continent, that has a latency that is worse than if you used a DNS in another european country.
Hi All, I think Quad9 uses round robin dns with server pools (3?) behind 9.9.9.9 anycast address: My findigs: $ for i in $(seq 0 9); do echo -n "$i "; dig +short @9.9.9.9 hostname.bind txt CH; sleep 3; done 0 "res300.ams.rrdns.pch.net" 1 "res300.ams.rrdns.pch.net" 2 "res100.ams.rrdns.pch.net" 3 "res200.ams.rrdns.pch.net" 4 "res200.ams.rrdns.pch.net" 5 "res200.ams.rrdns.pch.net" 6 "res300.ams.rrdns.pch.net" 7 "res200.ams.rrdns.pch.net" 8 "res300.ams.rrdns.pch.net" 9 "res300.ams.rrdns.pch.net" ... Quand9 dns server are not created equal: $ for i in $(seq 0 9); do echo -n "$i "; dig +short @9.9.9.9 version.bind txt CH; sleep 3; done 0 "Q9-U-5.0" 1 "Q9-P-5.0" 2 "Q9-U-5.0" 3 "Q9-P-5.0" 4 "Q9-P-5.0" 5 "Q9-U-5.0" 6 "Q9-P-5.0" 7 "Q9-P-5.0" 8 "Q9-P-5.0" 9 "Q9-P-5.0" E. -- | ENRICO ARDIZZONI | Responsabile Ufficio Reti e Sistemi | Università degli Studi di Ferrara