On Tue, 10 Dec 2019, Joe Maimon wrote:
Anyone have an idea why there are some destinations that on residential verizon fios here in NY area terminate right on first external hop?
They're returning fake ICMP echo replies from their BNGs for echo packets with TTL=1, thus any ICMP traceroute (Windows and mtr by default, etc.) seems to terminate at their layer 3 edge. UDP/TCP traceroute are unaffected, ICMP works fine if you set the initial TTL to n+1 where n is the hop that's lying.
Support claims that it was a mistake, but it's also been 15+ months and it's pretty deliberate behavior. Draw your own conclusions...
-Rob
