Strange IPv6 reachability problem

Jeroen Massar jeroen at
Mon Jun 20 00:59:23 CEST 2011

On 2011-06-20 00:40 , Seth Mattinen wrote:
>> 18  2607:fe70::14:2 (2607:fe70::14:2)  170.746 ms  175.756 ms  172.394 ms
>> 19  2607:fe70:1001::2 (2607:fe70:1001::2)  178.461 ms  178.177 ms *
>> 20  2607:fe70:1001::2 (2607:fe70:1001::2)  180.631 ms !N  177.091 ms !N
>>   177.261 ms !N
> Run it with ICMP.

Network unreachable is the wrong rejection ICMP for a administrative
denied packet. Quite a few operating systems cache !N's as it is
intended 'that network is unreachable...'.

Maybe you want to either drop those restrictive firewall rules and/or at
least look in the logs what is being dropped.

Nevertheless, the point stands, do you have a traceroute from
source->dest, as that might at least from that POV show where the path
is broken, a simple ping does not show that.


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