Route Flapping and Bird - RFD and MRAI

[Douglas Fischer]

Hello all.

Last weeks I'm noticing the increase the increase of BGP messages on some
routers that I have access to.
Specially those connected to IXPs with a considerable number of
participants.
I Checked and the BGP process has increased a bit the use of CPU Also.
So, I suspect that Route-Servers are receiving and forwarding Route Flaps
from one or more participants...

I know that the right place to fix that would be on the source of those
flaps...
But... Considering IXPs with one ou two thousand participants, there will
always be someone flapping some routes.

Bird is widely used as the BGP engine on IXP route-servers.
And exactly because of that I came here to ask about Route Flap avoidance
mechanisms on Bird.

The discussion of methods to avoid Route Flapping in BGP is very
controversial.
 - RFD - Route Flapping Dampening comes and goes.
 - MRAI is not a consensus, but there is a lot of effort on that, including
som magic algorithms define some variable interval according to conditions.
 - I even saw some ultra-rigorous ideas like rate limiting the BGP
messages...

Before I come here to bore you with this, I searched a bit on mail list and
documentation of Bird and I found the links bellow related to that:

There is any work running to deal with that route-flapping question?

https://bird.network.cz/ - 7.1 Future work
<https://bird.network.cz/?get_doc&v=20&f=bird-7.html>
Question about BGP advertisement-interval in BIRD
<http://trubka.network.cz/pipermail/bird-users/2020-August/014786.html>
[BGP] MRAI connection-based implementation review
<http://trubka.network.cz/pipermail/bird-users/2020-April/014433.html>
Route Flap Dampening
<http://trubka.network.cz/pipermail/bird-users/2019-July/013589.html>
[BGP] bird and RFD
<http://trubka.network.cz/pipermail/bird-users/2020-May/014612.html>

Thank you all!

-- 
Douglas Fernando Fischer
Engº de Controle e Automação
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://trubka.network.cz/pipermail/bird-users/attachments/20210708/f1d6e7fc/attachment.htm>