nanog mailing list archives
something strange about bgp community
From: Song Li <refresh.lsong () gmail com>
Date: Wed, 07 Jan 2015 21:35:35 +0800
Hi everyone,Today when I check one route in Routeviews I find something strange as follows:
route-views>sh ip bgp 176.108.0.0 BGP routing table entry for 176.108.0.0/19, version 23405621 Paths: (33 available, best #28, table default) Not advertised to any peer Refresh Epoch 1 202018 35320 35320 57800 5.101.110.2 from 5.101.110.2 (5.101.110.2) Origin IGP, localpref 100, valid, externalCommunity: 702:120 2914:429 20485:52990 20485:53990 20485:54040 20485:54050 47541:10001
rx pathid: 0, tx pathid: 0the AS-Path is "202018 35320 35320 57800" but the community is 702:120 2914:429 20485:52990 ....
According to RFC 1997, the community format is AA:NN and AA means the AS#. Here, AS702, AS2914 and AS20485 do not appear in the AS-Path and as a result they should not appear in the community. Could anybody tell me what's the reason they do appear in the community of this route?
Thanks! -- Song Li Room 4-204, FIT Building, Network Security, Department of Electronic Engineering, Tsinghua University, Beijing 100084, China Tel:( +86) 010-62446440 E-mail: refresh.lsong () gmail com
Current thread:
- something strange about bgp community Song Li (Jan 07)
- Re: something strange about bgp community Jared Mauch (Jan 07)
- Re: something strange about bgp community Christopher Morrow (Jan 07)
- Re: something strange about bgp community ML (Jan 07)
- Re: something strange about bgp community joel jaeggli (Jan 07)
- Re: something strange about bgp community Song Li (Jan 07)
- Re: something strange about bgp community Max Tulyev (Jan 08)
- Re: something strange about bgp community Christopher Morrow (Jan 08)
- Re: something strange about bgp community Jared Mauch (Jan 07)