Hi Bob, There are a lot of configuration options to do this.
A simple solution for this, hereby I assume that your secondary neighbor is accepting (default) bgp communities. Primary neighbor (default route): 1.1.1.1 AS10 Secondary neighbor (full table): 2.2.2.2 AS20 Local AS: AS30 Local prefixes: 3.3.3.0/24 and 4.4.4.0/24 Create as-path acl: ip as-path access-list 2 permit _20$ Create no-export access-list (specify your local/customer prefixes here): ip prefix-list no-export seq 1 permit 3.3.3.0/24 ip prefix-list no-export seq 2 permit 4.4.4.0/24 ip prefix-list no-export seq 10 deny 0.0.0.0/0 le 32 Create route-maps: --inbound-- route-map secondary-in permit 5 match as-path 2 set localpref 105 route-map secondary-in permit 10 set localpref 80 --outbound-- route-map secondary-out permit 5 match ip address prefix-list no-export set community no-export additive You don't have to change anything in the configuration of your primary neighbor, only put the in and outbound route-maps on the bgp session: Router bgp 30 Address-family ipv4 Neighbor 2.2.2.2 send-community Neighbor 2.2.2.2 route-map secondary-in in Neighbor 2.2.2.2 route-map secondary-out out Please make sure you also have an normal outbound prefix list on the session. If your secondary neighbor has a lot of 'local' routes which you want to send traffic to, but these routes are not originated from AS20. You should ask them if they can specify a customer bgp community. Afterwards you can match that community in the inbound route-map and set a localpref of 100+ to it. Regards, Tim -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of bobby hajhassan Sent: dinsdag, 13 april, 2010 10:01 To: [email protected] Subject: [c-nsp] BGP Multi-homing Turning up a backup BGP session with a secondary provider. Currently accepting a default route from my primary provider and will have full table from secondary. Would like to continue to have the primary provider as the preferred inbound/outbound path once i've turned up the secondary session. I would however like to prefer the local only routes from my secondary provider and have all other routes preferred through my primary. Config templete would be great...any help is appreciated. Thanks Bob _________________________________________________________________ Hotmail has tools for the New Busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_1 _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
