Voici la configuration des 2 routeurs avec un ibgp. R1 est connecté à AS100 transit primaire et R2 est connecté à AS200 transit de backup.
Sur la route-map IN du router2 j'ai ajouté un set local-preference (pref 50) inférieur au routeur1 (pref 100). Egalement sur le routeur2 j'ai ajouté un prepend sur la route-map out. Est-ce que cela ressemble à quelque chose de valable pour le mode transit Primaire/BACKUP ou je dois encore relire les docs Cisco ? #Router1 => AS100 (Transit Primaire) router bgp 10 bgp router-id A.A.A.1 network A.A.A.0 mask 255.255.255.0 neighbor 1.1.1.100 remote-as 100 neighbor 1.1.1.100 soft-reconfiguration inbound neighbor 1.1.1.100 route-map map-in in neighbor 1.1.1.100 route-map map-out out neighbor 1.1.1.100 filter-list 1 out neighbor A.A.A.2 remote-as 100 neighbor A.A.A.2 update-source Loopback0 neighbor A.A.A.2 next-hop-self ! ip as-path access-list 1 permit ^$ ip as-path access-list 100 permit ^100_ ! ip prefix-list filterv4_in seq 5 deny A.A.A.0/24 ip prefix-list filterv4_in seq 10 deny 0.0.0.0/0 ip prefix-list filterv4_in seq 15 deny 0.0.0.0/8 le 32 ip prefix-list filterv4_in seq 20 deny 10.0.0.0/8 le 32 ip prefix-list filterv4_in seq 25 deny 127.0.0.0/8 le 32 ip prefix-list filterv4_in seq 30 deny 169.254.0.0/16 le 32 ip prefix-list filterv4_in seq 35 deny 172.16.0.0/12 le 32 ip prefix-list filterv4_in seq 40 deny 192.0.2.0/24 le 32 ip prefix-list filterv4_in seq 45 deny 192.168.0.0/16 le 32 ip prefix-list filterv4_in seq 50 deny 224.0.0.0/3 le 32 ip prefix-list filterv4_in seq 55 permit 0.0.0.0/0 le 32 ! ip prefix-list filterv4_out seq 5 permit A.A.A.0/24 ip prefix-list filterv4_out seq 10 deny any ! route-map map-in deny 10 match ip address prefix-list filterv4_in ! route-map map-in permit 20 match as-path 100 set local-preference 100 ! route-map map-out permit 10 match ip address prefix-list filterv4_out ! #Router2 => AS200 (Transit Backup) router bgp 10 bgp router-id A.A.A.2 network A.A.A.0 mask 255.255.255.0 neighbor 2.2.2.200 remote-as 200 neighbor 2.2.2.200 soft-reconfiguration inbound neighbor 2.2.2.200 route-map map-in in neighbor 2.2.2.200 route-map map-out out neighbor 2.2.2.200 filter-list 1 out neighbor A.A.A.1 remote-as 100 neighbor A.A.A.1 update-source Loopback0 neighbor A.A.A.1 next-hop-self ! ip as-path access-list 1 permit ^$ ip as-path access-list 200 permit ^200_ ! ip prefix-list filterv4_in seq 5 deny A.A.A.0/24 ip prefix-list filterv4_in seq 10 deny 0.0.0.0/0 ip prefix-list filterv4_in seq 15 deny 0.0.0.0/8 le 32 ip prefix-list filterv4_in seq 20 deny 10.0.0.0/8 le 32 ip prefix-list filterv4_in seq 25 deny 127.0.0.0/8 le 32 ip prefix-list filterv4_in seq 30 deny 169.254.0.0/16 le 32 ip prefix-list filterv4_in seq 35 deny 172.16.0.0/12 le 32 ip prefix-list filterv4_in seq 40 deny 192.0.2.0/24 le 32 ip prefix-list filterv4_in seq 45 deny 192.168.0.0/16 le 32 ip prefix-list filterv4_in seq 50 deny 224.0.0.0/3 le 32 ip prefix-list filterv4_in seq 55 permit 0.0.0.0/0 le 32 ! ip prefix-list filterv4_out seq 5 permit A.A.A.0/24 ip prefix-list filterv4_out seq 10 deny any ! route-map map-in deny 10 match ip address prefix-list filterv4_in ! route-map map-in permit 20 match as-path 200 set local-preference 50 ! route-map map-out permit 10 match ip address prefix-list filterv4_out ! route-map map-out permit 20 set as-path prepend 10 10 10 ! --------------------------- Liste de diffusion du FRnOG http://www.frnog.org/
