Persistent BGP peer flapping - do you care?

Jake Khuon khuon at NEEBU.Net
Thu Jan 17 22:21:59 UTC 2002

### On Thu, 17 Jan 2002 17:00:06 -0500, "Christopher A. Woodfield"
### <rekoil at> casually decided to expound upon Susan Hares
### <skh at> the following thoughts about "Re: Persistent BGP peer
### flapping - do you care?":

CAW> I agree with your holddown timer proposal in cases of the peer being dropped due to 
CAW> errors, as the resultant loops can result in extreme prefix dampening. But my 
CAW> assertation is that BGP peering sessions should be a bit more robust and not drop 
CAW> everything at the first sign of trouble.

Well, as I recall, the original intent to drop the entire session and
thereby flush that peer from the table is because an invalid advertisement
may be symptomatic of a larger scale table corruption on the part of the
peer thus all advertisements should be invalidated.  Dropping the peer and
thereby initiating a coldstart/reset was the conservative solution.  I think
some form of peer damping with an exponential decay timer much like route
flap damping would be a good thing.  Simply reject the OPEN until the decay
timer has expired.

As for propogation of the bad prefix... well that soapbox has worn paint on
top.  If people aren't going to bother following specs in the first place
I'm not sure a new spec will solve anything.

/*===================[ Jake Khuon <khuon at NEEBU.Net> ]======================+
 | Packet Plumber, Network Engineers     /| / [~ [~ |) | | --------------- |
 | for Effective Bandwidth Utilisation  / |/  [_ [_ |) |_| N E T W O R K S |

More information about the NANOG mailing list