The following examples show how to configure Layer 3 VPN on the PE devices (PE1 and PE2) and MPLS segment (P1), and the GRE
tunnel from PE1 to P1 to PE2 (see Figure 1).
The following example shows how to configure loopback interface for GRE tunnel for PE1:
Device> enable
Device# configure terminal
Device(config)# interface Loopback4
Device(config-if)# ip address 209.165.200.230 255.255.255.255
Device(config-if)# end
The following example shows how to configure loopback interface for GRE tunnel for P1:
Device> enable
Device# configure terminal
Device(config)# interface Loopback100
Device(config-if)# ip address 209.165.200.235 255.255.255.255
Device(config-if)# end
The following example shows how to configure interface from PE1-P1 and configure IGP:
Device> enable
Device# configure terminal
Device(config)# interface Port-channel11
Device(config-if)# no switchport
Device(config-if)# ip address 209.165.201.1 255.255.255.248
Device(config-if)# ip ospf 10 area 0
Device(config-if)# end
The following example shows how to configure interface from P1-PE1 and configure IGP:
Device> enable
Device# configure terminal
Device(config)# interface Port-channel1
Device(config-if)# no switchport
Device(config-if)# ip address 209.165.201.2 255.255.255.248
Device(config-if)# ip broadcast-address 209.165.201.31
Device(config-if)# ip ospf 10 area 0
Device(config-if)# end
The following example shows how to advertise loopback in IGP on PE1:
Device> enable
Device# configure terminal
Device(config)# router ospf 10
Device(config-router)# router-id 198.51.100.10
Device(config-router)# network 209.165.200.230 0.0.0.0 area 0
Device(config-router)# end
The following example shows how to advertise loopback in IGP on P1:
Device> enable
Device# configure terminal
Device(config)# router ospf 10
Device(config-router)# router-id 198.51.100.20
Device(config-router)# network 209.165.200.235 0.0.0.0 area 0
Device(config-router)# end
The following example shows how to configure GRE tunnel, configure an IGP instance on the tunnel, and enable MPLS on the tunnel
on PE1:
Device> enable
Device# configure terminal
Device(config)# interface Tunnel111
Device(config-if)# ip address 209.165.202.140 255.255.255.248
Device(config-if)# ip ospf 11 area 0
Device(config-if)# mpls ip
Device(config-if)# tunnel source 209.165.200.230
Device(config-if)# tunnel destination 209.165.200.235
Device(config-if)# end
The following example shows how to configure GRE tunnel, configure an IGP instance on the tunnel, and enable MPLS on the tunnel
on P1:
Device> enable
Device# configure terminal
Device(config)# interface Tunnel111
Device(config-if)# ip address 209.165.202.141 255.255.255.248
Device(config-if)# ip ospf 11 area 0
Device(config-if)# mpls ip
Device(config-if)# tunnel source 209.165.200.235
Device(config-if)# tunnel destination 209.165.200.230
Device(config-if)# end
The following example shows how to advertise PE loopback IP for BGP in tunnel’s IGP instance on PE1:
Device> enable
Device# configure terminal
Device(config)# interface Tunnel111
Device(config)# router ospf 11
Device(config-router)# router-id 198.51.100.11
Device(config-router)# network 192.0.1.1 0.0.0.0 area 0
Device(config-router)# end
The following example shows how to configure interface from PE2-P1, and configure IGP and MPLS:
Device> enable
Device# configure terminal
Device(config)# interface Port-channel12
Device(config-if)# no switchport
Device(config-if)# ip address 209.165.201.1 255.255.255.248
Device(config-if)# ip ospf 11 area 0
Device(config-if)# mpls ip
Device(config-if)# end
The following example shows how to configure interface from P1-PE2, and configure IGP:
Device> enable
Device# configure terminal
Device(config)# interface Port-channel12
Device(config-if)# no switchport
Device(config-if)# ip address 209.165.201.2 255.255.255.248
Device(config-if)# ip ospf 11 area 0
Device(config-if)# mpls ip
Device(config-if)# end
The following example shows how to create VRF on PE1 where CE1 is connected:
Device> enable
Device# configure terminal
Device(config)# vrf definition vrf-1
Device (config-vrf)# rd 1:1
Device (config-vrf)# address-family ipv4
Device (config-vrf-af)# route-target import 1:2
Device (config-vrf-af)# route-target export 1:1
Device (config-vrf-af)# exit
Device (config-vrf)# end
The following example shows how to create VRF on PE2 where CE2 is connected:
Device> enable
Device# configure terminal
Device (config)# vrf definition vrf-1
Device (config-vrf)# rd 2:2
Device (config-vrf)# address-family ipv4
Device (config-vrf-af)# route-target import 1:1
Device (config-vrf-af)# route-target export 1:2
Device (config-vrf-af)# exit
Device (config-vrf)# end
The following example shows how to configure PE1-CE1 interface:
Device> enable
Device# configure terminal
Device (config)# int po14.1
Device (config-subif)# encapsulation dot1Q 10
Device (config-subif)# vrf forwarding vrf-1
Device (config-subif)# ip address 14.2.1.1 255.255.255.0
Device (config-subif)# exit
Device (config)# end
The following example shows how to configure PE2-CE2 interface:
Device> enable
Device# configure terminal
Device (config)# int po24.1
Device (config-subif)# encapsulation dot1Q 10
Device (config-subif)# vrf forwarding vrf-1
Device (config-subif)# ip address 24.2.1.1 255.255.255.0
Device (config-subif)# exit
Device (config)# end
The following example shows how to configure PE1-CE1 EBGP:
Device> enable
Device# configure terminal
Device (config)# router bgp 65040
Device (config-router)# address-family ipv4 vrf vrf-1
Device (config-router-af)# neighbor 14.2.1.2 remote-as 65041
Device (config-router-af)# neighbor 14.2.1.2 activate
Device (config-router-af)# exit-address-family
Device (config-router)# end
The following example shows how to configure PE2-CE2 EBGP:
Device> enable
Device# configure terminal
Device (config)# router bgp 65040
Device (config-router)# address-family ipv4 vrf vrf-1
Device (config-router-af)# neighbor 24.2.1.2 remote-as 65041
Device (config-router-af)# neighbor 24.2.1.2 activate
Device (config-router-af)# exit-address-family
Device (config-router)# end
The following example shows how to configure PE1-PE2 MP-BGP on PE1:
Device> enable
Device# configure terminal
Device (config)# router bgp 65040
Device (config-router)# neighbor 192.0.2.1 remote-as 65040
Device (config-router)# neighbor 192.0.2.1 update-source Loopback0
Device (config-router)# address-family ipv4
Device (config-router-af)# neighbor 192.0.2.1 activate
Device (config-router-af)# exit
Device (config-router)# address-family vpnv4
Device (config-router-af)# neighbor 192.0.2.1 activate
Device (config-router-af)# neighbor 192.0.2.1 send-community both
Device (config-router-af)# exit
Device (config-router)# end
The following example shows how to configure PE2-PE1 MP-BGP on PE2:
Device> enable
Device# configure terminal
Device (config)# router bgp 65040
Device (config-router)# neighbor 192.0.1.1 remote-as 65040
Device (config-router)# neighbor 192.0.1.1 update-source Loopback0
Device (config-router)# address-family ipv4
Device (config-router-af)# neighbor 192.0.1.1 activate
Device (config-router-af)# exit
Device (config-router)# address-family vpnv4
Device (config-router-af)# neighbor 192.0.1.1 activate
Device (config-router-af)# neighbor 192.0.1.1 send-community both
Device (config-router-af)# exit
Device (config-router)# end