[HECnet] All gone silent

[Thomas DeBellis]

The only thing that comes to mind immediately would be some kind of 
misguided attempt to mitigate possible DOS attacks via white listing.

On 8/16/21 9:04 PM, Paul Koning wrote:
>
>> On Aug 16, 2021, at 6:36 PM, Mark <mwjr at protonmail.com> wrote:
>>
>> Mystery solved (or at least the mystery of no response) - I used to have some issues when I ran authoratitive DNS and mail directly from our school's IP addresses rather than an 'established' (big tech co) source
> Why would that explain the failure to answer DNS queries?  DNS servers are supposed to answer queries from everyone.  I've never heard of failing to do so.  FWIW, I just tried asking ns1.protonmail.ch about mail.protonmail.ch, and it was happy to answer me (to my random Comcast client addresses, IPv4 and IPv6 both work).
>
> 	paul
>
>