Bird 1.6.3 removing IPv6 device routes on Linux (3.10.0)

[J Crowe]

Bringing up an old thread/issue.

I had hit this issue and changing metric to 32 helps, but I then introduced
an issue with reaching one or the other BGP session (I have set up). Says
"no route", though that's definitely not true.

Thanks
Joe Crowe.

On Mon, Feb 5, 2018 at 5:37 AM Ben Arblaster <ben at andatche.com> wrote:

>
>
> > On 1 Feb 2018, at 16:13, Ondrej Zajicek <santiago at crfreenet.org> wrote:
> >
> > On Wed, Jan 31, 2018 at 02:06:22PM +0000, Ben Arblaster wrote:
> >> Hi,
> >>
> >> I’m seeing an issue with bird 1.6.3 where IPv6 device routes are
> unexpectedly removed from the kernel table on Linux (3.10.0, CentOS 7) when
> bird removes a matching route learned via another protocol (in this case
> OSPF).
> >
> >> ...
> >
> >> This is a change in behaviour from 1.4.5 and seems like a bug, rather
> than the expected behaviour?
> >
> > Hi
> >
> > This is an unfortunate side-effect of IPv6 ECMP changes introduced in
> > 1.6.x. You can fix it by setting kernel protocol option 'metric' to e.g.
> > 32, see [*]. Also, the default value for kernel 'metric' has changed to
> > 32 in version 2.0.0.
>
> Thanks Ondrej, I suspected it was related to the IPv6 ECMP changes.
> Setting the kernel metric as suggested does resolve the problem.
>
> Regards,
> Ben
>
> --
> Ben Arblaster
> e: ben at andatche.com
> t: +447943860840
> w: https://andatche.com
>
>
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://trubka.network.cz/pipermail/bird-users/attachments/20191012/16dbc100/attachment.htm>