DHCP6 sometimes needs restart

[junicast]

Hi,

sometimes I need to restart DHCPv6 service. A client sends a dhcp6 solicitation but there will be no answer whatsoever from opnsense. When I just restart the service everything is going back to normal again.
Someone else whitnessed that behaviour?

I'm on 20.7.1 AMD64 on a PCEngline APU4. Very nice device though.

Thx

[gpb]

I'm exploring similar, but not using dhcpv6, using SLAAC instead.  Certainly sounds related so you might check out this thread:

https://forum.opnsense.org/index.php?topic=18549.0

[junicast]

Thank you. I agree. My radvd also dies. I restart it and boom, my clients again get autoconf addresses.
What a nasty bug.

[lebernd]

Hi,

my lan interfaces lose track on ipv6 after a wan reconnect. In the morning I go to a lan-interface and hit save...
this triggers some commands.
I wonder if you know the command for just getting dhcpv6 up again.

Best, Bernd

[gpb]

I noticed yesterday that if I save the WAN interface settings (even without changes) I also lose ipv6 on my LAN.  The only way I was able to recover ipv6 connectivity was to re-save the LAN interface settings, then I regain connectivity (once the RA unsolicited interval triggers).

[lebernd]

The good thing with this bad thing is, that you can also trigger the wan-interface reconfigure twice with cron (`configctl interface reconfigure`).

That worked for me too.

[norg]

I'm glad I'm not the only one with IPv6 issues :)

I don't have DHCPv6 running on OPNSense, since I have a static IPv6 net I just use SLAAC. So what got worse from 20.1 to 20.7 is the fact, that the IPv6 setting for the LAN interface stops working as well, while prior only clients lost it some time.

A workaround was, that when ever I had a PPPoE disconnect I did run `/var/etc/rtsold_pppoe0_script.sh` but that doesn't fix it now. If I go into the LAN interface section and don't change anything just press "apply" for the configuration again it will work. So there is something that's not triggering anymore when the WAN side receives updates.

I looked into the changelog but didn't find anything that leads to the obvious issue.

[iyzik]

I'm having this same exact issue after upgrading to 20.7 - super annoying. Dhcpv6 works for about 30 seconds after being restarted and then stops responding to anything until it is manually restarted again. Posting to watch this thread...

[junicast]

Did someone open up an issue for this on github? It would belong here, right?
https://github.com/opnsense/core/issues

[gpb]

Did someone open up an issue for this on github? It would belong here, right?
https://github.com/opnsense/core/issues

I don't see an issue opened there, but that is the right place.  I was waiting for feedback on my related issue of radvd not replying to solicitations (LAN), but that topic seems like it's going dead.  It's probably time to put it on github...been checking there and don't see anything related.

[marjohn56]

I didn't come back on the other thread as I'm not seeing the problem again. The only thing that's really different is that we were looking for another problem to do with bogons and I had a few 'tweaks' in place whilst we were trying to find the cause of that, I cannot see how it might cause the problem this topic is referring to, but it is fw related so try the patch and see if it makes any difference. patch ID 77aa218

[gpb]

Thanks @marjohn56.  I was curious if my log from the radvd I posted is similar to what you might have...that is...do you ever see advertisements in response to solicitations or is what I posted seemingly completely normal.  From everything I read, radvd should provide both unsolicited AND solicited adv's.  Is that true in the context of  opnsense?  Thanks...I'll try the patch!  :)

[marjohn56]

Yes I was seeing responses, but that was the issue, sometimes I'd see that RS followed by an RA, sometimes there was no RA, totally random.

[gpb]

Ah, ok.  It bothers me a bit the solution is to do a clean install, having a second setup.  I'll wait for now and see if the other issue with ipv6 dropping can be solved.  Again, much appreciated!