Mike Hughes wrote:
With the shorter timers or fast-external-fallover, a very short
maintenance slot at a large exchange can cause ripples in the routing
table. It would be interesting to do some analysis of this - how far the
ripples spread from each exchange!
We do BGP instability research, and this is something I'd like to
examine further. Compared to other sources of BGP noise, I don't
think it's a primary driver for the instability we monitor each
day, but I'd like to quantify it.
If people were willing to give us a heads-up after the fact when
there were .. um .. maintenance events at the major exchanges,
we could then go back and look at global propagation of the ripples
on fine timescales. --jim
p.s. The more eyes we have, the more we see, and we are always looking
for more silent peers, especially small and midsize providers or their
multihomed customers. See http://renesys.com/cgi-bin/bgpfeed to
sign up to send us a one-way multihop EBGP feed. It's quick, painless,
and you will be helping unravel the mysteries of why global routing works
so well in spite of us all.