[dns-operations] dnsviz.net complaining "UDP_-_NOEDNS_" for gtld-servers.net

[Stephane Bortzmeyer]

On Fri, Jun 05, 2020 at 11:26:55AM +0200,
 Thomas Mieslinger <miesi at mail.com> wrote 
 a message of 29 lines which said:

> I have a customer complaining being unable to send/receive email.

sportsproducts.net appear to DNS-work fine, so the problem is probably
elsewhere.

> https://dnsviz.net/d/sportsproducts.net/dnssec/
> 
> shows errors:
>     sportsproducts.net/DS: No response was received from the server
> over UDP (tried 12 times). (2001:502:1ca1::30, 2001:503:d414::30,
> 2001:503:eea3::30, UDP_-_NOEDNS_)

Timeout with Verisign name servers. Unfortunately, it is too common
with the IPv6 Internet. But, unless the resolver is v6-only, it does
not prevent DNS resolution (otherwise, no .net name would work). So,
it is probably not the reason why your customer has problems.

A test with the RIPE Atlas probes, to show that a few of them have the problem:

% blaeu-resolve --nameserver 2001:502:1ca1::30 -r 100 --dnssec -q DS sportsproducts.net
Nameserver 2001:502:1ca1::30
[] : 96 occurrences 
[TIMEOUT] : 3 occurrences 
Test #25636763 done at 2020-06-05T11:20:54Z