nanog mailing list archives
Re: What's the point of prepend communities?
From: Michael Hallgren <mh () xalto net>
Date: Mon, 30 Oct 2017 19:56:43 +0100
Hi guys, But keep in mind that 'prepend communities' are fragile: I decide by local preference whereto I send my traffic. Cheers, mh Le 30 oct. 2017 à 18:25, à 18:25, Leo Bicknell <bicknell () ufp org> a écrit:
In a message written on Thu, Oct 26, 2017 at 01:54:17PM -0600, Clinton Work wrote:I believe that Jason is asking about an ISP BGP community to prepend their AS when the BGP routes are received from the customer (not whenYeah, I typoed my example, should have been: There are paths: 1 2 3 5 1 2 4 5 If you prepend your ASN, you get: 1 1 2 3 5 1 1 2 4 5 No difference. If you send the ISP a prepend community for 3, you get: 1 2 2 3 5 1 2 4 5 And you just forced all traffic to the second, shorter path. For only customers that are dual homed to 3 & 4 without affecting other traffic. -- Leo Bicknell - bicknell () ufp org PGP keys at http://www.ufp.org/~bicknell/
Current thread:
- Re: What's the point of prepend communities?, (continued)
- Re: What's the point of prepend communities? Rob Foehl (Oct 28)
- Re: What's the point of prepend communities? William Herrin (Oct 26)
- Re: What's the point of prepend communities? William Herrin (Oct 26)
- RE: What's the point of prepend communities? Naslund, Steve (Oct 26)
- Re: What's the point of prepend communities? Brett Frankenberger (Oct 26)
- Re: What's the point of prepend communities? Steve Dodd (Oct 28)
- Re: What's the point of prepend communities? Leo Bicknell (Oct 26)
- Re: What's the point of prepend communities? Clinton Work (Oct 26)
- RE: What's the point of prepend communities? Naslund, Steve (Oct 26)
- Re: What's the point of prepend communities? Leo Bicknell (Oct 30)
- Re: What's the point of prepend communities? Michael Hallgren (Oct 30)
- Re: What's the point of prepend communities? Mike Hammett (Oct 29)
- Re: What's the point of prepend communities? Brett Frankenberger (Oct 29)