I agree that there appears to be some underlying problem with the BGP code on the backbone that is delaying route withdrawals beyond a reasonable time. We ran into a similar problem Wednesday night where one of our customers started advertising more specifics for our network blocks to another transit provider (who does not filter customer routes). After shutting down the customer's BGP peering, the bogus routes were still in the table an hour later at which time we started advertising our own more specifics to restore service to our other customers -- this lead to our unfortunate position in Thursday's CIDR report.
Were they in as dampened; history; or just in as if they were in and had not flapped? Dampening of more specific bogus announcements is a problem I'd like to see addressed, since the more general (and correct) routes won't be used if more specifics are dampened.
- Doug
Avi