ping6 www.freebsd.org hangs

[Lowell Gilbert]

Pierre Dupond <76nemo76 at gmx.ch> writes:

> Thanks for the tip. Finally I was able to reproduce the
> problem (which arise from time to time).
>
> The ping6 command failed either with the IPv6 address (or
> the name). The result is the same for an other address (like google)
> but at the same time I can reach these address from other machines.
>
> It is also possible to reach (with ping6) the external router of my organisation
> (passing few intermediate routers).
>
> What is curious however is that the command "traceroute6" succeed
> and then the command "ping6" works again.
>
> It sounds like a strange fragmentation problem.

By default traceroute uses UDP and ping uses ICMP.
Could be a stateful firewall somewhere.
You could test that by using ICMP with traceroute
if it happens again.