Direct protocol affects BGP

[Alexander Zubkov]

Do you disable direct protocol on both router1 and router2?
And that is definitely not the full bird config, you do not have a
kernel protocol for example.

On Tue, Mar 24, 2020 at 10:50 PM Fabiano D'Agostino
<fabiano.dagostino96 at gmail.com> wrote:
>
> There is no gateway because they are directly connected. However my network topology is the following:
> [pc-a - router1 ]=AS 1 ; [pc-b - router 2]=AS 2;
> pc-a:
> enp0s3
> address 192.168.1.11
> gw 192.168.1.1
> router1:
> enp0s3
> address 192.168.1.1
> enp0s8
> 192.168.2.2
>
> router1 bgp configuration:
> protocol bgp {
>     ipv4 {
>             import all;
>             export all;
>    }
> local as 1;
> neighbor 192.168.2.22 as 2
>
>
> Il giorno mar 24 mar 2020 alle ore 22:40 Alexander Zubkov <green at qrator.net> ha scritto:
>>
>> There is also no gateway in you "route" output on routes exported from
>> bird. Maybe you have some filters that causing it? Could you show your
>> config if it is not secret?
>>
>> On Tue, Mar 24, 2020 at 9:53 PM Fabiano D'Agostino
>> <fabiano.dagostino96 at gmail.com> wrote:
>> >
>> > Yes, 'show route', is from Bird. I don't have route-reflector, but just two routers which have a bgp session. Anyway, yes when direct is disabled, the bgp session is established.
>> >
>> > Il giorno mar 24 mar 2020 alle ore 21:45 Alexander Zubkov <green at qrator.net> ha scritto:
>> >>
>> >> "show route" looks a little weird, is it from bird? There are also
>> >> commonly a protocol and metric shown.
>> >> Those are from your route-reflector? Do you have your bgp sessions up
>> >> when direct is disabled?
>> >>
>> >> On Tue, Mar 24, 2020 at 9:33 PM Fabiano D'Agostino
>> >> <fabiano.dagostino96 at gmail.com> wrote:
>> >> >
>> >> > Good evening Alexander,
>> >> >
>> >> > Direct protocol enabled:
>> >> > 'route' command:
>> >> > Destination Gateway Genmask            Flags Metric iface
>> >> > 192.168.1.0      *        255.255.255.0       U       0         enp0s3
>> >> > 192.168.1.0      *        255.255.255.0       U       32       enp0s3
>> >> > 192.168.2.0      *        255.255.255.0       U       0         enp0s8
>> >> > 192.168.2.0      *        255.255.255.0       U        32      enp0s8
>> >> > 192.168.4.0      *        255.255.255.0       U        32      enp0s8
>> >> > 'show route' command:
>> >> > 192.168.1.0/24 enp0s3
>> >> > 192.168.2.0/24  enp0s8 via 192.168.2.22 on enp0s8
>> >> > 192.168.4.0/24 via 192.168.2.22 on enp0s8
>> >> >
>> >> > Direct protocol disabled:
>> >> > 'route' command:
>> >> > Destination Gateway Genmask            Flags Metric iface
>> >> > 192.168.1.0      *        255.255.255.0       U       0         enp0s3
>> >> > 192.168.2.0      *        255.255.255.0       U       0         enp0s8
>> >> > 'show route' command:
>> >> > empty
>> >> >
>> >> > Thanks,
>> >> >
>> >> > Fabiano
>> >> >
>> >> > Il giorno mar 24 mar 2020 alle ore 21:00 Alexander Zubkov <green at qrator.net> ha scritto:
>> >> >>
>> >> >> I think it would be easier if you showed your route tables in both cases.
>> >> >>
>> >> >> On Tue, Mar 24, 2020 at 8:57 AM Irene Lalioti <irene.lalioti at restena.lu> wrote:
>> >> >> >
>> >> >> > Hello guys!
>> >> >> >
>> >> >> > Just because today we encountered again the same issue with direct, I am very curious on this:
>> >> >> >
>> >> >> > I totally agree with what you guys explained about the need of the direct protocol. Once we set it then reachability works and all is ok.
>> >> >> >
>> >> >> > Our big question is why was it working before the moment it lost the BGP session?? In other words: the set up :
>> >> >> >
>> >> >> > RS - BGP session with the ROUTER - and behind the Router we have Caches.
>> >> >> >
>> >> >> > Before the router was announcing to the RS(BIRD v2.0.7) the caches and that they are reachable by the router. Without any direct.
>> >> >> >
>> >> >> > Until one day we lose the bgp session, and we can ping the caches from the RS but not reachable . Once we set it as direct on the bird then all is fine.
>> >> >> >
>> >> >> > Question is why was it working before without direct ?? :=)
>> >> >> >
>> >> >> > Many thanks for your time!
>> >> >> >
>> >> >> > Have a great day all!
>> >> >> >
>> >> >> > Irene.
>> >> >> >
>> >> >> > On 23/03/2020 17:07, Fabiano D'Agostino wrote:
>> >> >> >
>> >> >> > Hi Bernd,
>> >> >> > no, the routing "from the kernel" doesn't come via 'learn yes', but via RIB, I mean if I do 'route' it shows the directly connected networks. The problem is that if I use the Direct protocol, the command 'route' shows me two same directly connected networks, one coming from RIB and the other one coming from Bird.
>> >> >> > I tried protocol bgp { direct; }, but it doesn't change.
>> >> >> >
>> >> >> > Thanks,
>> >> >> >
>> >> >> > Fabiano
>> >> >> >
>> >> >> > Il giorno lun 23 mar 2020 alle ore 16:15 Bernd Naumann <bena at spreadshirt.net> ha scritto:
>> >> >> >>
>> >> >> >> On 23.03.20 16:01, Fabiano D'Agostino wrote:
>> >> >> >> > Hi Benedikt,
>> >> >> >> > I am just learning Bird and I didn't want to use the Direct protocol
>> >> >> >> > because using it I have two same routes in the RIB for the directly
>> >> >> >> > connected networks, one coming from the kernel and the second one coming
>> >> >> >> > from the direct protocol.
>> >> >> >>
>> >> >> >>
>> >> >> >> Is the routing "from the kernel" coming via `learn yes;`? If you have no
>> >> >> >> need to import "alien" routes, you can disable `learn` and just use
>> >> >> >> `direct` and `static` protocol. /* OR if you know that your neighbor is
>> >> >> >> directly connected to you can also set 'direct' on the `protocol bgp`. */
>> >> >> >>
>> >> >> >> Bernd
>> >> >> >>
>> >> >> >>
>> >> >> >
>> >> >> > --
>> >> >> > Irene Lalioti
>> >> >> > Network Engineer
>> >> >> > Fondation RESTENA
>> >> >> > 2, avenue de l'Université
>> >> >> > L-4365 Esch/Alzette
>> >> >> >
>> >> >> > Tel: +352 424409 1
>> >> >> > Fax: +352 422473