What could cause 0.0.0.0 (inaccessible) from 0.0.0.0 (<my loopback IP>) in FRR bgpd

[Peter Olsson]

Sorry about replying to myself, but I just noticed
that my problem only applies to IPv4, not IPv6.

bgpd> sh ip bgp ipv6 xxxx:yyy:1fe7::
BGP routing table entry for xxxx:yyy:1000::/36
Paths: (1 available, best #1, table default)
  Advertised to non peer-group peers:
  xxx
  Local
    :: from :: (<my IPv4 loopback IP>)
      Origin IGP, metric 0, weight 32768, valid, sourced, local, best (First path received)
      Last update: Mon Mar 28 05:26:07 2022

Could that give any clues?

Thanks!

Peter Olsson

On Mon, Mar 28, 2022 at 05:17:23AM +0200, Peter Olsson wrote:
> Hello!
> 
> I run FRR 7.5.1-1.1 in Debian 11.3.
> 
> I am trying to convert a quagga router to a frr router.
> I have come to the point that all BGP peers are up, and ospfd/ospf6d seem fine.
> 
> But I can't advertise my own networks in BGP, because of this:
>   Local
>     0.0.0.0 (inaccessible) from 0.0.0.0 (<my loopback IP>)
>       Origin IGP, metric 0, weight 32768, invalid, sourced, local
> 
> This problem applies to both connected interfaces and static routes.
> 
> I can't see the problem in my configuration and there are too many
> BGP peers and interfaces to anonymize all of it to be able to upload it.
> There are no confederations or reflectors, just a lot of ebgp peers and
> some ibgp peers in a full mesh.
> 
> The frr logs don't seem to contain anything useful, and google
> just gives me years old entries for that message or similar.
> 
> Where should I start looking for the problem?
> 
> 
> bgpd> sh ip bg x.y.z.46
> BGP routing table entry for x.y.z.0/23
> Paths: (2 available, best #1, table default)
>   Advertised to non peer-group peers:
>   xxx
>   Local
>     <ibgp peer> (metric 40) from <ibgp peer> (<ibgp peer>)
>       Origin IGP, metric 0, localpref 100, valid, internal, best (First path received)
>       Last update: Mon Mar 28 03:48:31 2022
>   Local
>     0.0.0.0 (inaccessible) from 0.0.0.0 (<my loopback IP>)
>       Origin IGP, metric 0, weight 32768, invalid, sourced, local
>       Last update: Mon Mar 28 03:47:50 2022
> 
> zebra> sh ip route x.y.z.46
> Routing entry for x.y.z.32/27
>   Known via "ospf", distance 110, metric 40
>   Last update 01:09:24 ago
>     <ospf neighbor, same as ibgp peer>, via enp196p0.107, weight 1
> 
> Routing entry for x.y.z.32/27
>   Known via "connected", distance 0, metric 0, best
>   Last update 01:09:41 ago
>   * directly connected, enp196p0.519
> 
> zebra> sh ip route <my loopback IP>
> Routing entry for <my loopback IP>/32
>   Known via "connected", distance 0, metric 0, best
>   Last update 00:57:29 ago
>   * directly connected, lo
> 
> htgr01-zebra> sh ip route 0.0.0.0
> Routing entry for 0.0.0.0/0
>   Known via "ospf", distance 110, metric 40
>   Last update 00:58:54 ago
>     <ibgp peer>, via enp196p0.107, weight 1
> 
> Routing entry for 0.0.0.0/0
>   Known via "static", distance 1, metric 0, best
>   Last update 00:59:11 ago
>   * x2.y2.z2.78, via veth-S, weight 1
> 
> 
> Thanks!
> 
> Peter Olsson