nanog mailing list archives
Re: Ingress filtering on transits, peers, and IX ports
From: Jared Mauch <jared () puck nether net>
Date: Wed, 14 Oct 2020 13:29:46 -0400
On Tue, Oct 13, 2020 at 05:49:42PM -0500, Brian Knight via NANOG wrote:
Hi Mel, My understanding of uRPF is: * Strict mode will permit a packet only if there is a route for the source IP in the RIB, and that route points to the interface where the packet was received * Loose mode will permit a packet if there is a route for the source IP in the RIB. It does not matter where the route is pointed. Strict mode won't work for us, because with our multi-homed transits and IX peers, we will almost certainly drop a legitimate packet because the best route is through another transit. Loose mode won't work for us, because all of our own prefixes are in our RIB, and thus the uRPF check on a transit would never block anything.
You'll be surprised at the garbage you would drop that you can't return. - Jared
Current thread:
- Re: Ingress filtering on transits, peers, and IX ports, (continued)
- Re: Ingress filtering on transits, peers, and IX ports Brian Knight via NANOG (Oct 19)
- Re: Ingress filtering on transits, peers, and IX ports Randy Bush (Oct 19)
- Re: Ingress filtering on transits, peers, and IX ports Baldur Norddahl (Oct 20)
- Re: Ingress filtering on transits, peers, and IX ports Brian Knight via NANOG (Oct 22)
- RE: Ingress filtering on transits, peers, and IX ports adamv0025 (Oct 23)
- Re: Ingress filtering on transits, peers, and IX ports Tim Durack (Oct 20)
- Re: Ingress filtering on transits, peers, and IX ports Marcos Manoni (Oct 20)
- Re: Ingress filtering on transits, peers, and IX ports Dobbins, Roland (Oct 20)
- Re: Ingress filtering on transits, peers, and IX ports Nick Hilliard (Oct 14)
- Re: Ingress filtering on transits, peers, and IX ports Mike Hammett (Oct 14)
- Re: Ingress filtering on transits, peers, and IX ports Jared Mauch (Oct 14)
- Re: Ingress filtering on transits, peers, and IX ports Chris Adams (Oct 13)
- Re: Ingress filtering on transits, peers, and IX ports Eric Kuhnke (Oct 13)
- Re: Ingress filtering on transits, peers, and IX ports Seth Mattinen (Oct 13)
- Re: Ingress filtering on transits, peers, and IX ports Casey Deccio (Oct 14)
- Re: Ingress filtering on transits, peers, and IX ports Mark Andrews (Oct 14)
- Re: Ingress filtering on transits, peers, and IX ports Bryan Holloway (Oct 14)
- Re: Ingress filtering on transits, peers, and IX ports Casey Deccio (Oct 14)
- Re: Ingress filtering on transits, peers, and IX ports Mel Beckman (Oct 14)