[dns-operations] NXDOMAIN rewriting by lying resolvers (Was: new public DNS service: 9.9.9.9

Wed Nov 22 20:27:15 UTC 2017

On Tue, Nov 21, 2017 at 05:48:06PM +0100,
 Andreas Teuchert <ant+dnsop at teuchert.org> wrote 
 a message of 22 lines which said:

> Deutsche Telekom, one of the biggest ISPs in Germany (biggest in
> Europe according to some sources), is doing that. They call it
> "Navigationshilfe".

Which AS? On AS 3320, I indeed see NXDOMAIN rewriting. But a majority
of RIPE Atlas probes (may be most of them are in proper networks, with
their own resolvers) see the honest answer:

% atlas-resolve -r 100 --as 3320 gwfhjdsyfhdsfgsyjfgshgfghqf56546FDRRFG.com
[104.239.213.7 198.105.244.11] : 1 occurrences 
[62.138.238.45 62.138.239.45] : 22 occurrences 
[ERROR: NXDOMAIN] : 75 occurrences 
Test #10290686 done at 2017-11-22T20:19:15Z