[158992] in North American Network Operators' Group
Re: 32-bit ASes at routeviews
daemon@ATHENA.MIT.EDU (John Kemp)
Tue Dec 18 17:25:13 2012
Date: Tue, 18 Dec 2012 14:24:58 -0800
From: John Kemp <kemp@network-services.uoregon.edu>
To: nanog@nanog.org
In-Reply-To: <AB63A1D3-B42C-461A-BFA8-5A1029B20FD3@muada.com>
Reply-To: kemp@network-services.uoregon.edu
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On 12/16/12 2:48 PM, Iljitsch van Beijnum wrote:
> Looking for 32-bit AS numbers, I get some strange results from routeviews:
>
> route-views>sh ip bgp regexp _23456_
> BGP table version is 2393809200, local router ID is 128.223.51.103
> Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
> r RIB-failure, S Stale
> Origin codes: i - IGP, e - EGP, ? - incomplete
>
> Network Next Hop Metric LocPrf Weight Path
> * 31.177.16.0/22 128.223.253.10 0 3582 3701 3356 23456 3.1043 i
> * 46.29.72.0/21 129.250.0.11 285 0 2914 12389 12389 12389 12389 23456 3.627 i
> * 46.243.96.0/21 154.11.11.113 0 0 852 174 39704 39704 23456 3.787 i
> * 91.208.62.0/24 154.11.11.113 0 0 852 174 39704 39704 23456 3.787 i
> * 91.217.87.0/24 194.85.40.15 0 3267 174 23456 3.661 i
> * 91.230.169.0/24 208.51.134.254 13905 0 3549 29152 29152 29152 29152 23456 23456 23456 23456 3.1426 i
> * 91.238.8.0/24 194.85.40.15 0 3267 8220 23456 3.2040 i
> * 111.235.148.0/22 194.85.40.15 0 3267 9498 9730 23456 i
> * 141.0.176.0/21 129.250.0.11 285 0 2914 12389 12389 12389 12389 23456 3.627 i
>
> Unless I missed something, AS 23456 is supposed to show up as a stand-in for 32-bit ASNs on 16-bit BGP implementations, not in _addition_ to 32-bit ASNs. So the penultimate line would make sense if the other lines weren't there and the others don't make sense period.
>
> Maybe a bug in the IOS they're running?
>
> route-views>sh ver
> Cisco IOS Software, 7200 Software (C7200P-ADVENTERPRISEK9-M), Version 12.4(24)T2, RELEASE SOFTWARE (fc2)
>
> Or is something else going on?
Off topic, this reminds me I would rather have ASPLAIN
again. We switched a couple of years ago on a particular
user request.
If there is no objection, I would love to switch back
ASAP. This would be on route-views, and on route-views3.
Just asking if others concur?
--
John Kemp (kemp@routeviews.org)
RouteViews Engineer
NOC: noc@routeviews.org
MAIL: help@routeviews.org
WWW: http://www.routeviews.org
