拓扑：
配置：
--------------------------R1------------------------
interface Loopback0
ip address 1.1.1.1 255.255.255.0
!
interface FastEthernet0/0
ip address 12.1.1.1 255.255.255.0
duplex auto
speed auto
router bgp 100
no synchronization
bgp router-id 1.1.1.1
bgp log-neighbor-changes
network 1.1.1.0 mask 255.255.255.0
neighbor 12.1.1.2 remote-as 200
no auto-summary
--------------------------R2---------------
interface Loopback0
ip address 2.2.2.2 255.255.255.255
!
interface FastEthernet0/0
ip address 12.1.1.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 23.1.1.2 255.255.255.0
duplex auto
speed auto
!
router ospf 100
router-id 2.2.2.2
log-adjacency-changes
network 2.2.2.2 0.0.0.0 area 0
network 23.1.1.0 0.0.0.255 area 0
!
router bgp 200
no synchronization
bgp router-id 2.2.2.2
bgp log-neighbor-changes
neighbor 3.3.3.3 remote-as 200
neighbor 3.3.3.3 update-source Loopback0
neighbor 3.3.3.3 next-hop-self
neighbor 12.1.1.1 remote-as 100
no auto-summary
------------------R3--------------
interface Loopback0
ip address 3.3.3.3 255.255.255.255
!
interface FastEthernet0/0
ip address 34.1.1.3 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 23.1.1.3 255.255.255.0
duplex auto
speed auto
!
router ospf 100
router-id 3.3.3.3
log-adjacency-changes
network 3.3.3.3 0.0.0.0 area 0
network 23.1.1.0 0.0.0.255 area 0
network 34.1.1.0 0.0.0.255 area 0
!
router bgp 200
no synchronization
bgp router-id 3.3.3.3
bgp log-neighbor-changes
neighbor 2.2.2.2 remote-as 200
neighbor 2.2.2.2 update-source Loopback0
neighbor 2.2.2.2 route-reflector-client
neighbor 4.4.4.4 remote-as 200
neighbor 4.4.4.4 update-source Loopback0
neighbor 4.4.4.4 route-reflector-client
no auto-summary
-----------------R4--------------------
interface Loopback0
ip address 4.4.4.4 255.255.255.255
!
interface FastEthernet0/0
ip address 34.1.1.4 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 45.1.1.4 255.255.255.0
duplex auto
speed auto
!
router ospf 100
router-id 4.4.4.4
log-adjacency-changes
network 4.4.4.4 0.0.0.0 area 0
network 34.1.1.0 0.0.0.255 area 0
!
router bgp 200
no synchronization
bgp router-id 4.4.4.4
bgp log-neighbor-changes
neighbor 3.3.3.3 remote-as 200
neighbor 3.3.3.3 update-source Loopback0
neighbor 45.1.1.5 remote-as 300
no auto-summary
-------------------R5-------------------
interface FastEthernet0/1
ip address 45.1.1.5 255.255.255.0
duplex auto
speed auto
!
router bgp 300
no synchronization
bgp router-id 5.5.5.5
bgp log-neighbor-changes
neighbor 45.1.1.4 remote-as 200
no auto-summary
验证：
