拓扑：

配置：

R1:

interface FastEthernet0/0 xconnect 7.7.7.7 10 encapsulation mpls

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R2: nterface FastEthernet0/0 xconnect 2.2.2.2 10 encapsulation mpls

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R4: router ospf 100 redistribute bgp 100 subnets router bgp 100 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 192.168.45.5 remote-as 200 ! address-family ipv4 neighbor 192.168.45.5 activate neighbor 192.168.45.5 send-label no auto-summary no synchronization network 2.2.2.2 mask 255.255.255.255 exit-address-family

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R5: router ospf 200 redistribute bgp 200 subnets router bgp 200 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 192.168.45.4 remote-as 100 ! address-family ipv4 neighbor 192.168.45.4 activate neighbor 192.168.45.4 send-label no auto-summary no synchronization network 7.7.7.7 mask 255.255.255.255 exit-address-family 其他配置是普通的mpls 配置，不在此给出。

验证：