Re: IPv6 default route flapping

[Martin Husemann <martin%duskware.de@localhost>]

On Tue, Apr 20, 2021 at 10:09:47AM -0400, Jan Schaumann wrote:
> That's unfortunately not very revealing, as it merely
> shows the neighbor solicitations and router advertisements:
> 
> IP6 fe80::7e12:b688:167c:785f > fe80::caa:49ff:feaf:1815: ICMP6, neighbor
> solicitation, who has fe80::caa:49ff:feaf:1815, length 32
> IP6 fe80::7e12:b688:167c:785f > ff02::1:ffaf:1815:
> ICMP6, neighbor solicitation, who has fe80::caa:49ff:feaf:1815, length 32
> IP6 fe80::7e12:b688:167c:785f > ff02::2: ICMP6, router solicitation, length 16
> IP6 fe80::7e12:b688:167c:785f > ff02::1:ffaf:1815:
> ICMP6, neighbor solicitation, who has fe80::caa:49ff:feaf:1815, length 32
> IP6 fe80::7e12:b688:167c:785f > ff02::1:ffaf:1815:
> ICMP6, neighbor solicitation, who has fe80::caa:49ff:feaf:1815, length 32
> IP6 fe80::caa:49ff:feaf:1815 > ff02::1: ICMP6, router advertisement, length 56

Well, adding -v or -vv would help here, especially to show the RA lifetime.

But more interesting is what happens on the routing socket, as that is
where dhcpcd gets the idea of reachability from.

You can see that with: route monitor

Martin