E-BGP and MPLS VPNs 341

B 192.168.3.8 [200/0] via 204.134.83.3, 00:03:06

C192.168.3.4 is directly connected, Serial0/1

In the routing table for vpn_1 on the Atlanta POP router, there are two BGP routes (B) and one static route (S). The BGP routes (B) are learned from the Raleigh POP router and are the result of the redistribute connected and redistribute static commands on the Raleigh POP router. The Atlanta POP router is configured with a static route for 192.168.1.1 that is displayed in the routing table as (S).

On the Raleigh POP router, there are also two BGP routes (B) and one static route (S). The BGP routes (B) are learned from the Atlanta POP router and are the result of the redistribute connected and redistribute static commands on the Atlanta POP router. The Raleigh POP router is configured with a static route for 192.168.2.1 that is displayed in the routing table as (S).

The routing table for vpn_1 on the Raleigh POP router is as follows:

Raleigh#show ip route vrf vpn_1

.

. Output Omitted

.

Gateway of last resort is not set

192.168.1.0 255.255.255.255 is subnetted, 1 subnets B 192.168.1.1 [200/0] via 204.134.83.1, 00:02:05

192.168.2.0 255.255.255.255 is subnetted, 1 subnets S 192.168.2.1 [1/0] via 192.168.3.10, Serial0/1

192.168.3.0 255.255.255.252 is subnetted, 2 subnets C 192.168.3.8 is directly connected, Serial0/1

B 192.168.3.4 [200/0] via 204.134.83.1, 00:02:05 Raleigh#

E-BGP and MPLS VPNs

Again, although the exam objectives do not call for you to know about E-BGP as a PE-CE routing protocol, I’d like to describe a working example of how E-BGP can be used in a simple MPLS VPN. Figure 8.3 contains the simple service provider network we’ll use in this section.

I-BGP

AS 65000

Table 8.3 lists the IP addresses and interfaces of the CE devices in

Figure 8.3.

T A B L E 8 . 3 Customer Addressing

E-BGP and MPLS VPNs 343

Table 8.4 lists the IP addresses and interfaces of the service provider devices in Figure 8.3.

Device Configuration

Presently, the network is set up with an IGP (RIPv2), tag switching, and MP-BGP between the Atlanta and Raleigh POP routers.

The configuration of the Raleigh POP router is as follows:

Raleigh#show running-config

Building configuration...

Current configuration : 1997 bytes

!

version 12.1

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname Raleigh

!

enable password cisco

!

!

!

!

!

memory-size iomem 25

344 Chapter 8 Advanced MPLS Topics

ip subnet-zero

ip tcp synwait-time 5 no ip domain-lookup

!

!

ip cef

cns event-service server

!

!

!

!

!

interface Loopback0

ip address 204.134.83.3 255.255.255.255

!

interface Serial0/0 no ip address shutdown

no fair-queue clockrate 64000

!

interface Serial0/1

description *** Link to Peer2 ***

ip address 192.168.3.9 255.255.255.252 clockrate 64000

!

interface Serial0/2 no ip address shutdown

clockrate 64000

!

interface Serial0/3

description *** Link to Core Router ***

ip address 204.134.83.10 255.255.255.252 tag-switching ip

E-BGP and MPLS VPNs 345

clockrate 64000

!

interface Ethernet1/0 no ip address shutdown

!

interface Ethernet1/1 no ip address shutdown

!

interface Ethernet1/2 no ip address shutdown

!

interface Ethernet1/3 no ip address shutdown

!

router rip version 2

network 204.134.83.0

!

router bgp 65000

no synchronization

bgp log-neighbor-changes

neighbor 204.134.83.1 remote-as 65000 neighbor 204.134.83.1 update-source Loopback0 neighbor 204.134.83.1 next-hop-self

no auto-summary

!

!

address-family vpnv4

neighbor 204.134.83.1 activate

neighbor 204.134.83.1 send-community both no auto-summary

exit-address-family

!

346 Chapter 8 Advanced MPLS Topics

ip classless

no ip http server

!

!

!

line con 0 exec-timeout 0 0 privilege level 15 logging synchronous transport input none

ip netmask-format decimal line aux 0

line vty 0 4 privilege level 15 password cisco logging synchronous login

ip netmask-format decimal

!

end

The configuration of the Atlanta POP router is as follows:

Atlanta#show running-config

Building configuration...

Current configuration : 1972 bytes

!

version 12.1

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname Atlanta

!

enable password cisco

!

!

E-BGP and MPLS VPNs 347

!

!

!

memory-size iomem 25 ip subnet-zero

ip tcp synwait-time 5 no ip domain-lookup

!

!

ip cef

cns event-service server

!

!

!

!

!

interface Loopback0

ip address 204.134.83.1 255.255.255.255

!

interface Serial0/0

description *** Link to Core Router ***

ip address 204.134.83.5 255.255.255.252 tag-switching ip

no fair-queue clockrate 64000

!

interface Serial0/1

description *** Link to Peer1 ***

ip address 192.168.3.6 255.255.255.252 clockrate 64000

!

interface Serial0/2 no ip address shutdown

clockrate 64000

!

348 Chapter 8 Advanced MPLS Topics

interface Serial0/3 no ip address shutdown

clockrate 64000

!

interface Ethernet1/0 no ip address shutdown

!

interface Ethernet1/1 no ip address shutdown

!

interface Ethernet1/2 no ip address shutdown

!

interface Ethernet1/3 no ip address shutdown

!

router rip version 2

network 204.134.83.0

!

router bgp 65000

no synchronization

bgp log-neighbor-changes

neighbor 204.134.83.3 remote-as 65000 neighbor 204.134.83.3 update-source Loopback0 neighbor 204.134.83.3 next-hop-self

no auto-summary

!

address-family vpnv4

neighbor 204.134.83.3 activate

neighbor 204.134.83.3 send-community both