Re: ipv6 gateway on different subnet

[Greg Troxel <gdt%lexort.com@localhost>]

Christof Meerwald <cmeerw%cmeerw.org@localhost> writes:

>> See netinet6/nd6_nbr.c and netinet6/nd6_rtr.c which might be
>> enlightening.
>
> Sorry, but not really sure what you are trying to get at.

I was responding partly to the idea that RA reception handling changed
in NetBSD.  One can skim that code and see what is still there, and see
various checks that cause packets to be ignored.

> We have two cases where the VPS receives a neighbor solicitation, and
> responds with a neighbor advertisement. There is a difference in the
> neighbor advertisement being sent, and only in the first case the VPS
> then receives a ping request, whereas in the second case no ping
> request is forwarded, but another neighbor solicitation.
>
> To me that means that something doesn't like the neighbor
> advertisement being sent in the second case (note, I am not saying
> that one of these neighbor advertisements is incorrect, I am only
> saying that something doesn't like that neighbor advertisement - maybe
> because of a misconfiguration in the network outside of the VPS).

It would seem that having "tcpdump -w" on both the VPS and the router at
the provider would be really helpful.

I am not 100% clear on ndp, but recall that with arp the arp request can
result (in the machine that receives the request) an arp entry, instead
of it only happening when a machine has sent a request and received a
response.