拓扑

配置过程

1.创建VRF；

2.R1,R2所有接口均绑定至VRF；

3.通过ospf打通L1的路由；

4.R1,R2使用G0/0接口建立EBGP邻居关系，并宣告L2的路由；

R1:

ip vrf ISP
 rd 1:1
 route-target both 1:1
!
interface GigabitEthernet 0/0
 ip vrf forwarding ISP
 ip address 10.1.1.1 255.255.255.0
!
interface Loopback 1
 ip vrf forwarding ISP
 ip address 1.1.1.1 255.255.255.255
!         
interface Loopback 2
 ip vrf forwarding ISP
 ip address 11.11.11.11 255.255.255.255
!
router bgp 65001
 bgp router-id 1.1.1.1
 bgp log-neighbor-changes
 bgp graceful-restart restart-time 120
 bgp graceful-restart stalepath-time 360
 bgp graceful-restart
 neighbor 10.1.1.2 remote-as 65002
 neighbor 10.1.1.2 ebgp-multihop 255
 neighbor 10.1.1.2 update-source GigabitEthernet 0/0
 address-family ipv4
  no neighbor 10.1.1.2 activate
  exit-address-family
!
 address-family ipv4 vrf ISP
  network 11.11.11.11 mask 255.255.255.255
  neighbor 10.1.1.2 remote-as 65002
  neighbor 10.1.1.2 activate
  exit-address-family
!
router ospf 101 vrf ISP
 graceful-restart
 area 0
 network 1.1.1.1 0.0.0.0 area 0
 network 10.1.1.1 0.0.0.0 area 0
!

R2:

ip vrf ISP
 rd 1:1
 route-target both 1:1
!
interface GigabitEthernet 0/0
 ip vrf forwarding ISP
 ip address 10.1.1.2 255.255.255.0
!
interface Loopback 1
 ip vrf forwarding ISP
 ip address 2.2.2.2 255.255.255.255
!         
interface Loopback 2
 ip vrf forwarding ISP
 ip address 22.22.22.22 255.255.255.255
!
router bgp 65002
 bgp router-id 2.2.2.2
 bgp log-neighbor-changes
 bgp graceful-restart restart-time 120
 bgp graceful-restart stalepath-time 360
 bgp graceful-restart
 neighbor 10.1.1.1 remote-as 65001
 neighbor 10.1.1.1 ebgp-multihop 255
 neighbor 10.1.1.1 update-source GigabitEthernet 0/0
 address-family ipv4
  no neighbor 10.1.1.1 activate
  exit-address-family
  !
 address-family ipv4 vrf ISP
  network 22.22.22.22 mask 255.255.255.255
  neighbor 10.1.1.1 remote-as 65001
  neighbor 10.1.1.1 activate
  exit-address-family
!
router ospf 101 vrf ISP
 graceful-restart
 network 2.2.2.2 0.0.0.0 area 0
 network 10.1.1.2 0.0.0.0 area 0