Missing IPv6 default route on protocol kernel and table master6

[Bernd Naumann]

Update:

On 2022-10-06  20:39, Bernd Naumann via Bird-users wrote:
> On 2022-10-06  15:11, Ondrej Zajicek wrote:
>> On Thu, Oct 06, 2022 at 11:37:18AM +0200, Bernd Naumann via Bird-users 
>> wrote:
>>> I may should have had a look at the log before :/
>>>
>>> ```
>>> Thu Oct  6 09:32:51 2022 daemon.err bird: KRT: Received route ::/0 with
>>> strange next-hop fe80::f6cc:55ff:fe42:1a94
>>> ```
>>>
>>> But why is this a strange a next-hop? Routes with via Link-Local 
>>> next-hop
>>> just work fine with OSPF and BGP, whats the issue here?
>>

This was bogus. I have tried to add a route explicit with `ip -6 route 
add default via LLA dev pppoe-wan` and forgot to remove it afterwards.

(But the local LLA, and the peer LLA are still present as host routes.)


If I use `protocol static`:
If I add `route ::/0 via "pppoe-wan"` to `protocol static`, then the 
route is present in `master6` it gets exported to `protocol kernel`.

This however works, **but** in case the PPP sessions fails, then the 
default route is still present.


If I add the route to the Linux Routing Table:
If I `ip -6 route add default dev pppoe-wan` then `protocol kernel` 
learns the route.
But then I still need to check the pppoe session, and remove this route 
if the session is down.


I would ratter prefer to understand why bird is unable to pick up the 
ipv6 default route on this pppoe device.