>> and it might even be possible to enforce some interesting
>> policies in that regard in the route servers (e.g. if you have more
>> than N routing or BGP peer transitions per time period, the route
>> server will refuse to peer with you for 48 hours - think of it as the
>> hold-down or damper from Hell).
Exponential backoff works well, too bad the code base that does
route flap damping isn't really stable enough for production
use in large parts of the Internet.
Best results are give, when everyone runs it.
Flap dampening works on most routers- just have to be aware of what
the effects are, particularly with multiple BGP Peers.
You have to decide whether to dampen outbound and/
or inbound, and if short duration events like temporary
recalculations of the IGP are considered a "flap".
Ed Segal EDS@RHQVM21.VNET.IBM.COM 914 684-3976