[39550] in North American Network Operators' Group
Re: Cisco's connected->bgp redistribution
daemon@ATHENA.MIT.EDU (Vijay Gill)
Fri Jul 13 18:00:05 2001
Date: Fri, 13 Jul 2001 17:59:17 -0400
From: Vijay Gill <vijay@umbc.edu>
To: Bill Woodcock <woody@zocalo.net>
Cc: <alex@yuriev.com>, <nanog@merit.edu>
In-Reply-To: <Pine.NEB.4.33.0107131332460.277-100000@woody.zocalo.net>
Message-ID: <Pine.SGI.4.31L.02.0107131750420.15043534-100000@irix2.gl.umbc.edu>
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On Fri, 13 Jul 2001, Bill Woodcock wrote:
>
> > Can anyone shed some light on why cisco ignores "ip classless" when
> > redistributing classless connected routes into bgp, making things such as
> > /30 into /24s?
>
> Because you forgot to append the "subnets" keyword to your redist.
Subnets are not needed, chances are it is a failure of no auto-summary.
Autosummary is on by default.
router#show ip route x.y.106.122
Routing entry for x.y.106.120/30
Known via "connected", distance 0, metric 0 (connected, via interface)
Redistributing via bgp abcd
Advertised by bgp abcd route-map connected-to-bgp
Routing Descriptor Blocks:
* directly connected, via Serial2/0/0:0
Route metric is 0, traffic share count is 1
router#show int Serial2/0/0:0
Serial2/0/0:0 is up, line protocol is up
Hardware is Multichannel T1
Description: by the perception of illusion we experience reality
Internet address is x.y.106.122/30
router bgp abcd
no synchronization
bgp log-neighbor-changes
bgp dampening
redistribute connected route-map connected-to-bgp
redistribute static route-map static-to-bgp
no auto-summary
!
ip classless
router#show ip bgp x.y.106.122
BGP routing table entry for x.y.106.120/30, version 11186014
Paths: (1 available, best #1)
etc
If you have no auto-summary turned on, then there might be a bug or more
probably, some sort of typo or mismatch (pilot error).
/vijay
