IPv6 routes not imported into Kernel

[Gerdriaan Mulder]

Hi Robert,

On 27/02/2024 22:58, Robert Finze wrote:
> In the meantime I've setup a clean new VM with Ubuntu 22.04 and the same 
> issues occurred.
> I've upgraded that new VM to 24.04 and still the same.
> 
> Next I want to try a fresh 20.04 install and see what happens.

I would try a fresh install of Ubuntu 20.04 with the same kernel as the 
machine that currently works, indeed. If the problem goes away, it might 
be an issue between Ubuntu 20.04 and 22.04. If the problem persists, it 
might be some subtle configuration difference. I wouldn't yet upgrade to 
BIRD 3.0alpha because that changes too many variables in order to debug 
the problem.

 >> ip -6 route add 2607:ff00:b::/40 via 2a0e:3940:dead::1 table 254 
protocol bird scope global src 2a0e:3940:1000::2 dev 2
>> - where dev 2 indicates the network interface with index 2, this is probably ens20 in your setup?
> 
> It should be ens19. I'm currently not sure how to verify that.
> "ip a" shows:
> 
> 1: lo
> 2: ens18
> 3: ens19
> 4: ens20
> 5: dummy0 

The number before ":" is the interface index. It seems BIRD wants to add 
the route on device ens18 (at least, at the time).

Besides, in your initial post, you pasted a few routes from BIRD that 
were using protocols "upstream_1v6" and "upstream_2v6". They seem to be 
missing from the bird.conf you posted. The route addition in the netlink 
dump is different from the routes you showed in BIRD, which makes it 
more difficult to pinpoint the problem.

I think it's a good idea to focus on getting just one route exported 
from BIRD to the kernel successfully. If it's possible in your setup, 
perhaps just configure 1 upstream, and only import 1 route from that 
upstream in BIRD, and export the same route through the kernel protocol.

Best regards,
Gerdriaan Mulder