[c-nsp] BGP load balancing with dCEF

[Ihsan Junaidi Ibrahim]

Previously BGP maximum-path is not enabled but I've enabled that just
before I took the configuration snapshot. My understanding is that
multipath is only used for peers connected via multiple routers which
is not the case here.

On 10/10/06, Ihsan Junaidi Ibrahim <ihsan.junaidi at gmail.com> wrote:
> Hi,
>
> The peer interfaces are all located on the same router and so do us.
> It's an eBGP peering. and the problem is that traffic always flow
> heaviest on the fourth interface. Most of the time, the first 3 links
> are idle.
>
> Here's the required output:
> ---
> rtr-2#sh ip bgp 202.75.130.4
> BGP routing table entry for 202.75.128.0/19, version 48155320
> Paths: (3 available, best #2)
>   Advertised to peer-groups:
>      ibgp-neighbor
>   6453 9534, (received & used)
>     216.6.121.9 from 216.6.121.9 (66.110.0.81)
>       Origin IGP, localpref 100, valid, external
>   9534, (received & used)
>     202.75.134.1 from 202.75.134.1 (202.75.134.1)
>       Origin IGP, metric 0, localpref 100, valid, external, best
>   2914 9534, (received & used)
>     203.78.193.57 from 203.78.193.57 (203.78.192.1)
>       Origin IGP, metric 0, localpref 100, valid, external
>       Community: 190972314 190974311 190975304
> ---
>
> rtr-2#sh ip route 202.75.130.4
> Routing entry for 202.75.128.0/19, supernet
>   Known via "bgp 9930", distance 20, metric 0
>   Tag 9534, type external
>   Last update from 202.75.134.1 00:08:35 ago
>   Routing Descriptor Blocks:
>   * 202.75.134.1, from 202.75.134.1, 00:08:35 ago
>       Route metric is 0, traffic share count is 1
>       AS Hops 1, BGP network version 48155320
> ---
>
> rtr-2#sh ip route 202.75.134.1
> Routing entry for 202.75.134.1/32
>   Known via "static", distance 1, metric 0
>   Tag 1
>   Redistributing via ospf 100, bgp 9930
>   Advertised by bgp 9930
>   Routing Descriptor Blocks:
>     203.121.99.2
>       Route metric is 0, traffic share count is 1
>     203.121.99.6
>       Route metric is 0, traffic share count is 1
>     203.121.99.10
>       Route metric is 0, traffic share count is 1
>   * 203.121.99.14
>       Route metric is 0, traffic share count is 1
>
> On 10/10/06, Oliver Boehmer (oboehmer) <oboehmer at cisco.com> wrote:
> > cisco-nsp-bounces at puck.nether.net <> wrote on :
> >
> > > Hi all,
> > >
> > > We're having trouble doing per-destination load balancing on outgoing
> > > BGP traffic over 4 x E1 links. It's a 7507 (12.0(26)S) with dCEF
> > > enabled (globally and on the interfaces). Whenever I do a show ip cef
> > > xxx.xx, there's only 1 next-hop entry instead of 4. How do I get all 4
> > > next-hop entries to be installed?
> >
> > Are you installing multiple BGP paths into your RIB, i.e. did you
> > specify "maximum-paths 4" in your BGP config, or how is your setup?
> > Please show a "show ip bgp <prefix>", "show ip route <bgp-prefix>" and
> > "show ip route <bgp-next-hop-of-this-prefix>".
> >
> >         ol
> >
>
>
> --
> Thank you for your time,
> Ihsan Junaidi Ibrahim
>


-- 
Thank you for your time,
Ihsan Junaidi Ibrahim