Re: ipv6 gateway on different subnet

[Christof Meerwald <cmeerw%cmeerw.org@localhost>]

On Mon, Jan 20, 2025 at 07:07:57PM -0600, Peter Miller wrote:
> Here's the results from Debian.
> 
> sudo ip -6 addr add 2602:fed2:7116:d82c::d/64 dev eth0
> sudo tcpdump -npi vioif0 -vw icmp6.pcap icmp6
[...]
> I don't see the echo request or reply on NetBSD, which I guess is showing that ping is failing.

The main difference is that I don't see a neighbor solicitation from
the router for the VPS's IPv6 address - maybe that was already
somehow triggered when adding the IP address?

Could you re-run it one more time and make sure you start the tcpdump
before adding the new IP address?


> 
> Debian the request comes from my vps to the router, the router replies and theres a 'router' flag
> 2602:fed2:7116:d82c::d > ff02::1:ff00:1: [icmp6 sum ok] ICMP6, neighbor solicitation, length 32, who has 2602:fed2:7116::1
> 2602:fed2:7116::1 > 2602:fed2:7116:d82c::d: [icmp6 sum ok] ICMP6, neighbor advertisement, length 32, tgt is 2602:fed2:7116::1, Flags [router, solicited, override]
> 
> NetBSD seems to be going the other direction. Assuming this because the router is trying to find my server to send the echo request to it.

Yes, and that step seems to be missing for the Debian side.


Christof

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