nanog mailing list archives
Re: Blackhole Routes
From: Pete Templin <petelists () templin org>
Date: Thu, 30 Sep 2004 14:42:15 -0500
Deepak Jain wrote:
If providers start tying their customer's blackhole announcements to the provider's upstreams' blackhole announcements in an AUTOMATIC process, bad things <tm> are likely to happen. What happens when a customer of a provider mistakenly advertises more routes than he should [lets say specifics in case #1] you can flood your upstreams' routers with specifics and potentially cause flapping or memory overflows...In case #2, presumably the blackhole community takes precedence, so if a customer is mistakenly readvertising their multihome provider's table with a 666 tag, all of the upstream providers might be blackholing the majority of their non-customer routes.
I build two prefix lists for each customer. One represents the exact match routes that I'm willing to propagate, and the other covers "le 32" more specifics of what I'm willing to allow special treatment on. They can't blackhole anything outside what they would otherwise be allowed to announce (and I use it for several other special cases as well). Customers who are single-homed and otherwise static routed are welcome to use BGP for these special cases; their prefix lists reflect the fact that their space is not to be propagated.
pt
Current thread:
- Re: Blackhole Routes, (continued)
- Re: Blackhole Routes Mark Kasten (Sep 30)
- Re: Blackhole Routes Richard A Steenbergen (Sep 30)
- Re: Blackhole Routes Jeff Aitken (Sep 30)
- Re: Blackhole Routes Christopher L. Morrow (Sep 30)
- Re: Blackhole Routes Randy Bush (Sep 30)
- Re: Blackhole Routes Christopher L. Morrow (Sep 30)
- Re: Blackhole Routes Will Yardley (Sep 30)
- Re: Blackhole Routes Stephen J. Wilcox (Sep 30)
- Re: Blackhole Routes Richard A Steenbergen (Sep 30)
- Re: Blackhole Routes Stephen J. Wilcox (Sep 30)
- Re: Blackhole Routes Pete Templin (Sep 30)
- Re: Blackhole Routes Deepak Jain (Sep 30)
- Re: Blackhole Routes Christopher L. Morrow (Sep 30)
- Re: Blackhole Routes Petri Helenius (Sep 30)