rejected by protocol <prefix> unicast

[Ondrej Zajicek]

On Wed, Dec 11, 2019 at 09:06:15AM +0100, Eric GITAU wrote:
> On Wed, Dec 11, 2019 at 3:19 AM Ondrej Zajicek <santiago at crfreenet.org>
> > Hi
> >
> > This 'rejected by protocol' is completely harmless. That just means pe1
> > reject it back - no need to send the route back to the peer.
> 
> 
> Thanks for the explanation, and I actually did see the "rejected by
> protocol" line in the logs (below) when I reconfigured using a different
> address family (vpn4 mpls).
> ...
> Probably minor but "show route" seems to display both tables, master4 &
> t_pe1 (below) when i used vpn4 mpls address family but not when ipv4
> unicast AF is used.

Yes, 'show route' by defaults show one (default) table per type. If you
define vpn4 mpls routing table, then it becames the default one for that
type (as there is no implicit vpn4 mpls routing table). While there is
already default master4 for ipv4.


> > No, the reason why the route is shown in 'show route protocol' but not
> > regular 'show route' is that BGP is connected to table t_pe1, while
> > Kernel is connected to (default) table master4. The first command shows
> > by default routes in table attached to the specified protocol, while the
> > second one shows routes in default table. But you do not have connection
> > between these tables (using pipe protocol), so BGP routes stay in t_pe1
> > and are not in master4, so that is another reason why they are not
> > exported to the kernel.
> >
> 
> Explains a lot!  I had missed the part about being in master4 to be
> exported to the kernel and another use case for peer tables.
> 
> A (most likely dump) question that's unrelated to the current topic:
> - is it possible to discard the route distinguisher from vpn4 mpls prefix
> (essentially changing the AF to labelled unicast) while retaining the
> labelled next hop ? maybe during export to kernel ?

That is currently not supported. Therefore, applicability of vpn4 mpls in
BIRD is limited to route reflectors.

-- 
Elen sila lumenn' omentielvo

Ondrej 'Santiago' Zajicek (email: santiago at crfreenet.org)
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"To err is human -- to blame it on a computer is even more so."