跨运营商的MPLS ×××解决方案1

实验拓扑：

 

配置：

R1（CE）：

interface Loopback0 ip address 1.1.1.1 255.255.255.255 ! interface FastEthernet0/0 ip address 192.168.12.1 255.255.255.0 duplex auto speed auto ! router rip version 2 network 1.0.0.0 network 192.168.12.0 no auto-summary

R2（PE1）

ip vrf a rd 1:1 route-target export 1:1 route-target import 1:1 route-target import 2:2 mpls label range 200 299 mpls label protocol ldp interface Loopback0 ip address 2.2.2.2 255.255.255.255 ! interface FastEthernet0/0 ip vrf forwarding a ip address 192.168.12.2 255.255.255.0 duplex auto speed auto ! interface FastEthernet0/1 ip address 192.168.23.2 255.255.255.0 duplex auto speed auto mpls ip ! router ospf 100 router-id 2.2.2.2 log-adjacency-changes network 2.2.2.2 0.0.0.0 area 0 network 192.168.23.0 0.0.0.255 area 0 ! router rip ! address-family ipv4 vrf a redistribute bgp 100 metric transparent network 192.168.12.0 no auto-summary version 2 exit-address-family ! router bgp 100 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 3.3.3.3 remote-as 100 neighbor 3.3.3.3 update-source Loopback0 ! address-family ***v4 neighbor 3.3.3.3 activate neighbor 3.3.3.3 send-community extended exit-address-family ! address-family ipv4 vrf a redistribute rip no synchronization exit-address-family mpls ldp router-id Loopback0

R3(RR)：

mpls label range 300 399 mpls label protocol ldp interface Loopback0 ip address 3.3.3.3 255.255.255.255 ! interface FastEthernet0/0 ip address 192.168.34.3 255.255.255.0 duplex auto speed auto mpls ip ! interface FastEthernet0/1 ip address 192.168.23.3 255.255.255.0 duplex auto speed auto mpls ip ! router ospf 100 router-id 3.3.3.3 log-adjacency-changes network 3.3.3.3 0.0.0.0 area 0 network 192.168.23.0 0.0.0.255 area 0 network 192.168.34.0 0.0.0.255 area 0 ! router bgp 100 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 2.2.2.2 remote-as 100 neighbor 2.2.2.2 update-source Loopback0 neighbor 6.6.6.6 remote-as 200 neighbor 6.6.6.6 ebgp-multihop 255 neighbor 6.6.6.6 update-source Loopback0 ! address-family ***v4 neighbor 2.2.2.2 activate neighbor 2.2.2.2 send-community extended neighbor 2.2.2.2 route-reflector-client neighbor 6.6.6.6 activate neighbor 6.6.6.6 send-community extended neighbor 6.6.6.6 next-hop-unchanged exit-address-family ! mpls ldp router-id Loopback0

R4(PE-ASBR):

mpls label range 400 499 mpls label protocol ldp interface Loopback0 ip address 4.4.4.4 255.255.255.255 ! interface FastEthernet0/0 ip address 192.168.34.4 255.255.255.0 duplex auto speed auto mpls ip ! interface FastEthernet0/1 ip address 192.168.45.4 255.255.255.0 duplex auto speed auto ! router ospf 100 router-id 4.4.4.4 log-adjacency-changes redistribute bgp 100 subnets network 4.4.4.4 0.0.0.0 area 0 network 192.168.34.0 0.0.0.255 area 0 ! 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 no auto-summary no synchronization network 2.2.2.2 mask 255.255.255.255 network 3.3.3.3 mask 255.255.255.255 exit-address-family ! mpls ldp router-id Loopback0

R5(PE-ASBR):

mpls label range 500 599 mpls label protocol ldp interface Loopback0 ip address 5.5.5.5 255.255.255.255 ! interface FastEthernet0/0 ip address 192.168.56.5 255.255.255.0 duplex auto speed auto mpls ip ! interface FastEthernet0/1 ip address 192.168.45.5 255.255.255.0 duplex auto speed auto ! router ospf 200 router-id 5.5.5.5 log-adjacency-changes redistribute bgp 200 subnets network 5.5.5.5 0.0.0.0 area 0 network 192.168.56.0 0.0.0.255 area 0 ! 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 no auto-summary no synchronization network 6.6.6.6 mask 255.255.255.255 network 7.7.7.7 mask 255.255.255.255 exit-address-family ! mpls ldp router-id Loopback0

R6(RR):

mpls label range 600 699 mpls label protocol ldp interface Loopback0 ip address 6.6.6.6 255.255.255.255 ! interface FastEthernet0/0 ip address 192.168.56.6 255.255.255.0 duplex auto speed auto mpls ip ! interface FastEthernet0/1 ip address 192.168.67.6 255.255.255.0 duplex auto speed auto mpls ip ! router ospf 200 router-id 6.6.6.6 log-adjacency-changes network 6.6.6.6 0.0.0.0 area 0 network 192.168.56.0 0.0.0.255 area 0 network 192.168.67.0 0.0.0.255 area 0 ! router bgp 200 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 3.3.3.3 remote-as 100 neighbor 3.3.3.3 ebgp-multihop 255 neighbor 3.3.3.3 update-source Loopback0 neighbor 7.7.7.7 remote-as 200 neighbor 7.7.7.7 update-source Loopback0 ! address-family ***v4 neighbor 3.3.3.3 activate neighbor 3.3.3.3 send-community extended neighbor 3.3.3.3 next-hop-unchanged neighbor 7.7.7.7 activate neighbor 7.7.7.7 send-community extended neighbor 7.7.7.7 route-reflector-client exit-address-family ! mpls ldp router-id Loopback0

R7(PE):

mpls label range 700 799 mpls label protocol ldp interface Loopback0 ip address 7.7.7.7 255.255.255.255 ! interface FastEthernet0/0 ip vrf forwarding b ip address 192.168.78.7 255.255.255.0 duplex auto speed auto ! interface FastEthernet0/1 ip address 192.168.67.7 255.255.255.0 duplex auto speed auto mpls ip ! router ospf 200 router-id 7.7.7.7 log-adjacency-changes network 7.7.7.7 0.0.0.0 area 0 network 192.168.67.0 0.0.0.255 area 0 ! router rip ! address-family ipv4 vrf b redistribute bgp 200 metric transparent network 192.168.78.0 no auto-summary version 2 exit-address-family ! router bgp 200 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 6.6.6.6 remote-as 200 neighbor 6.6.6.6 update-source Loopback0 ! address-family ***v4 neighbor 6.6.6.6 activate neighbor 6.6.6.6 send-community extended exit-address-family ! address-family ipv4 vrf b redistribute rip no synchronization exit-address-family ! mpls ldp router-id Loopback0

R8(CE)：

interface Loopback0 ip address 8.8.8.8 255.255.255.0 ! interface FastEthernet0/0 ip address 192.168.78.8 255.255.255.0 duplex auto speed auto ! router rip version 2 network 8.0.0.0 network 192.168.78.0 no auto-summary

验证：

分析：

数据从R8(CE)发出进入R7的vrf b

从上图可以到数据包 打双层标签，

204是ISPA R2给1.1.1.1分配的标签并且通过MP-EBGP带到R7

 

603是R6 给1.1.1.1下一跳2.2.2.2分配的标签

数据包进入R6，

从上图可以看出603 是untagged 标签全部被弹出，一个没有标签的数据包发送给R5，

到R5以后不带标签的数据包R5无法处理丢弃，所以导致数据包无法到达对端。

解决方案：

R4：

router bgp 100
address-family ipv4
neighbor 192.168.45.5 send-label

R5：

router bgp 200
address-family ipv4
neighbor 192.168.45.4send-label

查看：

从上图可以看出 已经分配了标签也就是说 R6到R5的数据包不是IPV4 变成了标签交换。

验证：

结论：

在mpls ××× 中LDP 标签要贯通整个MP-BGP的路径数据包才可以通信。