Strange behavior with IPv6 on PPPoE [was: DynDNS for IPv6 not working]

[franco]

I think I found it while reviewing something else:

https://github.com/opnsense/core/commit/fc2ea5dee

# opnsense-patch fc2ea5dee

Does that work for you?


Cheers,
Franco

[glasi]

Still trying to reproduce the issues...

[schnipp]

Hi franco,

thanks, I'll check this next week and report back.

[franco]

This patch also indicates an issue even more so than the other one: https://github.com/opnsense/core/commit/05bb00812


Cheers,
Franco

EDIT: But might not be working. Sorry for stabbing in the dark. This is still eludes common sense somehow.

[schnipp]

So, I tested both patches (fc2ea5dee and 05bb00812), but still noch difference in behavior. In general after boot up no IPv6 address is assigned to the pppoe interface using SLAAC, after performing a pppoe reconnect the address is properly assigned to the pppoe interface.

Further obversations:

• SLAAC (without "Use IPv4 connectivity"): DynDNS cannot identify the correct WAN interace and tries to use the IPv6 from the parent interface (ix0)
• SLAAC (with "Use IPv4 connectivity"): DynDNS works fine and properly registers the IPv6 address of the pppoe interface
• Configuring the pppoe interface with a static IPv6 incorrectly assigns the configured IPv6 address to the parent interface (ix0)

I looks like there are still problems with identifying the correct interface and possibly some more bugs. Does anybody have an idea, how to debug the scripts running in the background?

[franco]

I think SLAAC assignment itself is broken away from our code somehow, but I can't easily inspect this because PPPoE and SLAAC is pretty circumstantial and I don't have access to it. :(


Cheers,
Franco

[schnipp]

I think it is not related to SLAAC and PPPoE only, because when setting a static IPv6 address for the interface pppoe0 in the GUI, the address is assigned to the parent interface ix0. The same behavior occurs if the static IPv6 address is set for a VLAN child interface of ix0.

@franco: Do you have an idea, how to easily debug some of the scripts?

[franco]

To me it seems you are describing leaving "Use IPv4 connectivity" unchecked. The setting exists for SLAAC, Static IPv6 and DHCPv6.


Cheers,
Franco

[schnipp]

Oh, I am not sure if this option was activated with static IPv6 and DHCP. I'll do a new series of tests at end of next week and report again.

[franco]

Ok, and if you are on 19.1.7 can you ping me on https://github.com/opnsense/core/issues/2267 as I have all the code ready now and we can get to the bottom of it.


Cheers,
Franco

[schnipp]

Thanks, next monday I can start testing the pppoe patches.

Going ahead in this thread and start testing the assignment of IPv6 addresses to the network interfaces need some more time, because I am very busy at the moment.