17 Aug
2021
17 Aug
'21
3:08 a.m.
On 8/16/21 9:04 PM, Paul Koning wrote:
Probably misguided paranoia. I've been to companies who blocked ICMP
on their networks (breaking important things like path MTU discovery)
because they thought people could "hack in" that way.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
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).