Re: IPv6 networking problems in 14.3

From: Chris Ross <cross+freebsd_at_distal.com>
Date: Wed, 17 Sep 2025 04:07:50 UTC 

> On Sep 16, 2025, at 23:24, Chris Ross <cross+freebsd@distal.com> wrote:
>> 
>>> 
>>> On Sep 15, 2025, at 15:05, Tom Pusateri <pusateri@keehole.org> wrote:
>>> 
>>> I would try running the 14.3p2 system without the VLAN configuration and a direct connection to the upstream provider hardware (no switch) and see if the problem persists. That will determine if it’s a VLAN issue.
>> 
>> That would be a bit of work.  I have an available ix port, so I can run a line to the machine
>> without vlan. It would still be a VLAN in the switch, because running a direct line is not
>> possible without much rewiring and very long cables.
> 
> So this is my next attempt.

So, reconfiguring this wasn’t as hard as I feared.  But, it’s not working.  I’m getting
an IPv4 address as before, surprisingly even the same one, on my ix1 interface.  I’ve
changed interface names in rc.conf, pf.conf, and dhcpcd.conf.  However, dhcpcd is now
doing something different.  Only changing the interface name in the config, I’m not sure
why.

Sep 16 23:47:34 [98787]: ix1: soliciting an IPv6 router
Sep 16 23:47:34 [98787]: ix1: sending Router Solicitation
Sep 16 23:47:34 [98787]: ix1: Router Advertisement from fe80::3e8a:b0ff:fe3e:4dce
Sep 16 23:47:34 [98787]: ix1: no global addresses for default route
Sep 16 23:47:34 [98787]: ix1: executing: /usr/local/libexec/dhcpcd-run-hooks ROUTERADVERT
Sep 16 23:47:34 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 1.1 seconds
Sep 16 23:47:36 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 2.0 seconds
Sep 16 23:47:38 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 4.2 seconds
Sep 16 23:47:42 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 8.9 seconds
Sep 16 23:47:51 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 17.8 seconds
Sep 16 23:48:03 [98787]: timed out
Sep 16 23:48:03 [98492]: forked to background
Sep 16 23:48:09 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 37.9 seconds
Sep 16 23:48:47 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 71.2 seconds
Sep 16 23:49:58 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 142.0 seconds
Sep 16 23:52:20 [98787]: ix1: multicasting SOLICIT6 (xid 0x1e9737), next in 274.4 seconds

Where as before, when it was not getting the answer to NS, it was simply doing:

Sep 15 14:00:58 [10047]: vlan0: soliciting an IPv6 router
Sep 15 14:00:58 [10047]: vlan0: sending Router Solicitation
Sep 15 14:00:58 [10047]: vlan0: Router Advertisement from fe80::3e8a:b0ff:fe3e:4dce
Sep 15 14:00:58 [10047]: vlan0: no global addresses for default route
Sep 15 14:00:58 [10047]: lo0: adding reject route to 2600:4040:2c9d:5200::/56 via ::1
Sep 15 14:00:58 [10047]: vlan0: executing: /usr/local/libexec/dhcpcd-run-hooks ROUTERADVERT
Sep 15 14:00:58 [10047]: vlan0: multicasting REBIND6 (xid 0x0a7d83), next in 1.0 seconds
Sep 15 14:00:58 [10047]: vlan0: REPLY6 received from fe80::3e8a:b0ff:fe3e:4dce
Sep 15 14:00:58 [10047]: vlan0: renew in 3600, rebind in 5760, expire in 7200 seconds
Sep 15 14:00:58 [10047]: vlan0: writing lease: /var/db/dhcpcd/vlan0.lease6
Sep 15 14:00:58 [10047]: vlan0: delegated prefix 2600:4040:aaaa:bb00::/56
Sep 15 14:00:58 [10047]: int1: adding address 2600:4040:aaaa:bb12::1/64
Sep 15 14:00:58 [10047]: int1: pltime 7200 seconds, vltime 7200 seconds
Sep 15 14:00:58 [10047]: int1: waiting for DHCPv6 DAD to complete

Oh.  So with a new interface, dhcpcd isn’t trying to REBIND, so it’s a different
process. I’m not seeing any response to the SOLICIT messages, but I admit that I
wasn’t watching the DHCPv6 ports earlier, only the ICMP6, so this may not be
new.

This is all for tonight.  I’ll try more tomorrow.  Thanks all for your time.

- Chris