[141892] in North American Network Operators' Group
Re: bgp feed to customer
daemon@ATHENA.MIT.EDU (William Herrin)
Mon Jun 13 15:38:29 2011
In-Reply-To: <BANLkTikyOvqS002sspsS2SRK=-mgDuJ7TA@mail.gmail.com>
From: William Herrin <bill@herrin.us>
Date: Mon, 13 Jun 2011 15:34:23 -0400
To: Richard Zheng <rzheng@gmail.com>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Mon, Jun 13, 2011 at 1:25 PM, Richard Zheng <rzheng@gmail.com> wrote:
> This is probably a typical setup for border router not speaking BGP, wond=
er
> how to handle it properly. Border router B is connected with customer rou=
ter
> C. Router C wants default-only/partial/full routes. Router B can't or is =
not
> willing to handle it. Router C has a multihop EBGP session with a backbon=
e
> router A. To get router B know the customer routes, router A redistribute=
s
> them from EBGP to OSPF.
>
> The issue is redistribution from EBGP to OSPF works half way. OSPF databa=
se
> has the external routes, but forwarding address is set to Router A. So th=
e
> routing loop occurs between A and B.
>
> I wonder if it is a design issue or configuration issue?
>
> =A0---------- =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0-------------- =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 ------------
> | BGP rtr A | =A0=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D | no-BGP rtr B | =
=A0=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D | Customer C |
> =A0---------- =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0-------------- =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 ------------
Hi Richard,
Just a SWAG, but run IBGP on router B with just your internal routes
(including the customer route) instead of exporting into OSPF?
Regards,
Bill Herrin
--=20
William D. Herrin ................ herrin@dirtside.com=A0 bill@herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004
