Information Technology Reference
In-Depth Information
Example 4-54
BGP RIB on R7
R7#show ip bgp
BGP table version is 5, local router ID is 192.168.57.7
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 172.15.0.0 192.168.57.5 0 300 100 2 i
* 192.168.47.4 0 200 100 2 i
*> 172.16.0.0 0.0.0.0 0 32768 i
Now AS 2 can convince AS 300 to change its peering and, thus, R5's configuration. Local
AS is not needed on R2. However, AS 200 will only honor its previous peering agreement
with AS 100. Local AS is still needed between R1 and R4. To maintain the same forwarding
policy, R2 now needs to prepend its AS_PATH outbound to R5. The final configuration of
R2 is shown in Example 4-55. The BGP RIB on R7 is shown in Example 4-56.
Example 4-55
BGP Configuration on R2
router bgp 2
network 172.15.0.0
neighbor 192.168.12.1 remote-as 2
neighbor 192.168.23.3 remote-as 2
neighbor 192.168.25.5 remote-as 300
neighbor 192.168.25.5 weight 100
neighbor 192.168.25.5 route-map Path-300 out
!
route-map Path-300 permit 10
set as-path prepend 2
Example 4-56
BGP RIB on R7
R7#show ip bgp
BGP table version is 10, local router ID is 192.168.57.7
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* 172.15.0.0 192.168.47.4 0 200 100 2 i
*> 192.168.57.5 0 300 2 2 i
*> 172.16.0.0 0.0.0.0 0 32768 i
