Select default routes in BGP

dd99onedd · ‎04-03-2008

Hi,

My company has 2 large sites with internet access and 2 small sites with NO internet access. All of the sites are connected via an MPLS cloud. I would like to inject the default routes from both large sites into the BGP MPLS cloud and configue the 2 small sites to pick one as primary and the other as secondary. I have attached a network diagram and here are the details:

SITE A:

-Pick Site B's default route as primary

-Pick Site D's default route as secondary

SITE B:

-Has internet connection

-Default route is injected into EBGP via a static route, redistribute into eigrp and advertise to EBGP via the network 0.0.0.0 command

SITE C:

-Pick Site D's default route as primary

-Pick Site B's default route as secondary

SITE D:

-Has internet connection

-Default route is injected into EBGP via a static route, redistribute into eigrp and advertise to EBGP via the network 0.0.0.0 command

Does anyone have any suggestions or bgp config examples on how to accomplish this?

Thanks

Giuseppe Larosa · ‎04-03-2008

Hello,

just one question are you sites inside a MPLS VPN and you manage the CE routes or you have control of PE/LSR routers at each site ?

If this your case you can change the weight or the local preference of incoming BGP advertisements to provide the selection hierarchy you want.

To be selective a route-map could be used and you can set the weight or the local preference for prefix 0.0.0.0/0 (using a prefix-list to specify it) and using also a match ip next-hop acl where you specify the site A or site B PE/LSR loopback address

Instead, if you are in a MPLS VPN and you can control only CE routers you have to ask your provider to do this job for you on the

PE routers of site A and B.

Hope to help

Giuseppe

dd99onedd · ‎04-03-2008

I can only control my CE routers. Thanks for the post.