On Wed, 2022-11-16 at 08:43 -0300, Roberto Bartzen Acosta wrote:
> Hey folks,
>
> Please, I have a question here, the bgpspeaker should only "learn" and not
> "advertise" the AS_PATHs via BGP, right?

its been a while since i looked at it but in the past it did not supprot learning at all

it just advertised the routes for the neutron netowrks

>
> In my tests, I can see that it is learning routes from BGP neighbors. This
> behavior can cause an AS_PATH loop because the bgpspeaker learns back its
> own advertised routes, and I see a message like this in the logs:
>
> 2022-11-11 19:45:41.967 7220 ERROR bgpspeaker.peer [-] AS_PATH on UPDATE
> message has loops. Ignoring this message:
> BGPUpdate(len=91,nlri=[],path_attributes=[BGPPathAttributeMpReachNLRI(afi=2,flags=144,length=46,next_hop='2001:db7:1::1',nlri=[IP6AddrPrefix(addr='2001:db9:1234::',length=64)],safi=1,type=14),
> BGPPathAttributeOrigin(flags=64,length=1,type=1,value=0),
> BGPPathAttributeAsPath(flags=80,length=10,type=2,value=[[65001,
> 65000]])],total_path_attribute_len=68,type=2,withdrawn_routes=[],withdrawn_routes_len=0)
>
> This can be fixed by suppressing the neighbor route advertisement (using
> route-map export), but have I misunderstood how neutron-dymanic-routing
> works or do we have a possible bug here?
>
> Regards
>