Enterasys Networks X-PeditionTM Ebgp Peer Group Example, BGP Community with Route Maps Examples

Configuring BGP Peer Groups

XSR(config-router)#neighbor IBGP filter-list 1 out

XSR(config-router)#neighbor IBGP filter-list 2 in

XSR(config-router)#neighbor 192.168.57.3 peer-group IBGP

XSR(config-router)#neighbor 192.168.57.4 peer-group IBGP

XSR(config-router)#neighbor 192.168.57.5 peer-group IBGP

XSR(config-router)#neighbor 192.168.57.5 filter-list 3 in

EBGP Peer Group Example

Peer group EBGP in this example is defined not using the neighbor remote-ascommand, rendering it an EBGP peer group by definition. Each peer group member is supplied with its respective AS number separately so the peer group is composed of members from AS’s 25, 35, and

45.All peer group members have route map 5 as an outbound route map and filter-list 4 as an outbound filter list and all share incoming filter list 57 except neighbor 192.168.57.10.

XSR(config)#router bgp 13 XSR(config-router)#neighbor external-peers peer-group XSR(config-router)#neighbor external-peers route-map 5 out XSR(config-router)#neighbor external-peers filter-list 4 out XSR(config-router)#neighbor external-peers filter-list 57 in XSR(config-router)#neighbor 192.168.57.2 remote-as 25 XSR(config-router)#neighbor 192.168.57.2 peer-group external-peers XSR(config-router)#neighbor 192.168.57.9 remote-as 35 XSR(config-router)#neighbor 192.168.57.9 peer-group external-peers XSR(config-router)#neighbor 192.168.57.10 remote-as 45 XSR(config-router)#neighbor 192.168.57.10 peer-group external-peers XSR(config-router)#neighbor 192.168.57.10 filter-list 45 in

BGP Community with Route Maps Examples

This section illustrates three examples of BGP communities with route maps. First, route map 111 is applied to outgoing updates for neighbor 192.168.57.50. The routes that pass ACL 1 share the no-export community attribute while other routes are advertised as usual. This community value automatically bars BGP speakers in AS 20 from advertising those routes.

XSR(config)#router bgp 10

XSR(config-router)#neighbor 192.168.57.50 remote-as 20

XSR(config-router)#neighbor 192.168.57.50 send-community

XSR(config-router)#neighbor 192.168.57.50 route-map 111 out

XSR(config-router)#route-map 111 10 permit

XSR(config-route-map)#match ip address 1

XSR(config-route-map)#set community no-export

XSR(config-route-map)#route-map 111 20 permit

XSR(config-route-map)#match ip address 2

Secondly, route map 111 is matched with outgoing updates for neighbor 192.168.57.90. All routes originating from AS 7 have the community values 50 50 added to their existing values with other routes advertised as usual.

XSR(config)#router bgp 20

XSR(config-router)#neighbor 192.168.57.90 remote-as 10

6-26 Configuring the Border Gateway Protocol