IPv4 route via IPv6 next hop: Netlink: Network unreachable

[Nico Schottelius]

Hey Ondrej,

Ondrej Zajicek <santiago at crfreenet.org> writes:
>> I'm running 2.0.7 on Linux 5.4.18-0-lts (Alpine)
>> and I receive the route 193.228.143.0/24 from
>> 2a0a:e5c0:1:9::2. However it is never set into the kernel, with the
>> error message "Netlink: Network unreachable" in syslog.
>>
>> Has anyone seen this problem recently? I'm not sure if this is really a
>> bird2 problem or not, to be honest:
>
> Hello
>
> BIRD 2.0.7 does not support properly putting IPv4 routes with IPv6 next
> hops to kernel, you can try git master branch (or apply commit
> 53401bef63013dfee01b65d071ffbd88e457539f to v2.0.7). Or wait for 2.0.8,
> which will be released hopefully this month.

Thanks for the reminder - I somehow thought that one was already
released. I'll wait for 2.0.8 and give you feedback then.

>> The kernel reports many messages like this in dmesg:
>> [4541983.369058] netlink: 'bird': attribute type 5 has an invalid length.
>>
>> However, I am also puzzled that manually adding the route seems to fail:
>
> Probably older iproute2 tools?

It seems to be related to alpine Linux, however pretty recent

diamond2:~# apk list -I | grep -e iproute -e linux-lts
linux-lts-5.4.30-r0 x86_64 {linux-lts} (GPL-2.0) [installed]
iproute2-doc-5.6.0-r0 x86_64 {iproute2} (GPL-2.0-or-later) [installed]
iproute2-5.6.0-r0 x86_64 {iproute2} (GPL-2.0-or-later) [installed]
diamond2:~#

I'm currently in touch with the Alpine folks to debug this.

Cheers,

Nico


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