拓扑设计

各自配置IP
[r1]int lo0
[r1-LoopBack0]ip add 1.1.1.1 24

[r1-LoopBack0]int g0/0/1
[r1-GigabitEthernet0/0/1]ip add 12.1.1.1 24

[r2]int lo0
[r2-LoopBack0]ip add 2.2.2.2 24

[r2-LoopBack0]int g0/0/0
[r2-GigabitEthernet0/0/0]ip add 12.1.1.2 24

[r2-GigabitEthernet0/0/0]int g0/0/1
[r2-GigabitEthernet0/0/1]ip add 23.1.1.1 24

[r3-LoopBack0]ip add 3.3.3.3 24

[r3-LoopBack0]int g0/0/0
[r3-GigabitEthernet0/0/0]ip add 23.1.1.2 24

[r3-GigabitEthernet0/0/0]int g0/0/1
[r3-GigabitEthernet0/0/1]ip add 34.1.1.1 24

[r4]int lo0
[r4-LoopBack0]ip add 4.4.4.4 24

[r4-LoopBack0]int g0/0/0
[r4-GigabitEthernet0/0/0]ip add 34.1.1.2 24

[r4-GigabitEthernet0/0/0]int g0/0/1
[r4-GigabitEthernet0/0/1]ip add 45.1.1.1 24

[r4-GigabitEthernet0/0/1]int g0/0/2
[r4-GigabitEthernet0/0/2]ip add 54.1.1.1 24

[r5]int lo0
[r5-LoopBack0]ip add 5.5.5.5 24

[r5-LoopBack0]int g0/0/0
[r5-GigabitEthernet0/0/0]ip add 45.1.1.2 24

[r5-GigabitEthernet0/0/0]int g0/0/2
[r5-GigabitEthernet0/0/2]ip add 54.1.1.2 24
配置OSPF
[r2]ospf 1 router-id 2.2.2.2
[r2-ospf-1-area-0.0.0.1]network 2.2.2.2 0.0.0.0
[r2-ospf-1-area-0.0.0.1]network 23.1.1.1 0.0.0.0

[r3]ospf 1 router-id 3.3.3.3
[r3-ospf-1]area 1
[r3-ospf-1-area-0.0.0.1]network 3.3.3.3 0.0.0.0
[r3-ospf-1-area-0.0.0.1]network 23.1.1.2 0.0.0.0

[r4-GigabitEthernet0/0/2]ospf 1 r 4.4.4.4
[r4-ospf-1]area 1
[r4-ospf-1-area-0.0.0.1]network 4.4.4.4 0.0.0.0
[r4-ospf-1-area-0.0.0.1]network 34.1.1.2 0.0.0.0
BGP
建邻

[r1]BGP 1

[r1-bgp]router-id 1.1.1.1

[r1-bgp]peer 12.1.1.2 as-number 2

r2-ospf-1]bgp 2
[r2-bgp]router-id 2.2.2.2
[r2-bgp]peer 12.1.1.1 as-number 1

[r2]bgp 2
[r2-bgp]peer 3.3.3.3 as
[r2-bgp]peer 3.3.3.3 as-number 2

[r3-bgp]router-id 3.3.3.3
[r3-bgp]pee
[r3-bgp]peer 2.2.2.2 as
[r3-bgp]peer 2.2.2.2 as-number 2

[r2-bgp]peer 3.3.3.3 connect-interface LoopBack 0

[r3-bgp]peer 2.2.2.2 connect-interface LoopBack 0

[r3-bgp]peer 4.4.4.4 as-number 2
[r3-bgp]peer 4.4.4.4 connect-interface LoopBack 0

[r4-bgp]router-id 4.4.4.4
[r4-bgp]peer 3.3.3.3 as-number 2
[r4-bgp]peer 3.3.3.3 connect-interface LoopBack 0

[r4-bgp]peer 5.5.5.5 as-number 3
[r4-bgp]peer 5.5.5.5 connect-interface LoopBack 0

[r4]ip route-static 5.5.5.5 32 45.1.1.2
[r4]ip route-static 5.5.5.5 54.1.1.2

[r5-bgp]router-id 5.5.5.5
[r5-bgp]peer 4.4.4.4 as-number 2
[r5-bgp]peer 4.4.4.4 connect-interface LoopBack 0

[r5]ip route-static 4.4.4.4 32 45.1.1.1
[r5]ip route-static 4.4.4.4 32 54.1.1.1

[r4-bgp]peer 5.5.5.5 ebgp-max-hop 2

[r5-bgp]peer 4.4.4.4 ebgp-max-hop 2

宣告

[r1-bgp]network 1.1.1.1 24

[r2-bgp]peer 3.3.3.3 next-hop-local

[r2-bgp]peer 4.4.4.4 as-number 2
[r2-bgp]peer 4.4.4.4 connect-interface LoopBack 0
[r2-bgp]peer 4.4.4.4 next-hop-local

[r4-bgp]peer 2.2.2.2 as-number 2
[r4-bgp]peer 2.2.2.2 connect-interface LoopBack 0
[r4-bgp]peer 2.2.2.2 next-hop-local

[r5-bgp]network 5.5.5.5 24