Configuring an OSPFv3 sham link
Network requirements
As shown in Figure 66, CE 1 and CE 2 belong to VPN 1. Configure an OSPFv3 sham link between PE 1 and PE 2 so traffic between CE 1 and CE 2 is forwarded through the MPLS backbone, instead of the backdoor link.
Figure 66: Network diagram
Table 20: Interface and IP address assignment
Device | Interface | IP address | Device | Interface | IP address |
|---|---|---|---|---|---|
CE 1 | Vlan-int11 | 100::1/64 | CE 2 | Vlan-int11 | 120::1/64 |
Vlan-int13 | 20::1/64 | Vlan-int12 | 30::2/64 | ||
PE 1 | Loop0 | 1.1.1.9/32 | PE 2 | Loop0 | 2.2.2.9/32 |
Loop1 | 3::3/128 | Loop1 | 5::5/128 | ||
Vlan-int11 | 100::2/64 | Vlan-int11 | 120::2/64 | ||
Vlan-int12 | 10.1.1.1/24 | Vlan-int12 | 10.1.1.2/24 | ||
Switch A | Vlan-int11 | 30::1/64 | |||
Vlan-int12 | 20::2/64 |
Configuration procedure
Configure OSPFv3 on the customer networks.
Configure conventional OSPFv3 on CE 1, Switch A, and CE 2 to advertise subnet addresses of the interfaces as shown in Figure 66. Set the cost value to 2 for both the link between CE 1 and Switch A, and the link between CE 2 and Switch A. Execute the display ipv6 routing-table command to verify that CE 1 and CE 2 have each learned the OSPFv3 route to VLAN-interface 11 of the other. (Details not shown.)
Configure IPv6 MPLS L3VPN on the backbone:
# Configure basic MPLS and MPLS LDP on PE 1 to establish LDP LSPs.
<PE1> system-view [PE1] interface loopback 0 [PE1-LoopBack0] ip address 1.1.1.9 32 [PE1-LoopBack0] quit [PE1] mpls lsr-id 1.1.1.9 [PE1] mpls ldp [PE1-ldp] quit [PE1] interface vlan-interface 12 [PE1-Vlan-interface12] ip address 10.1.1.1 24 [PE1-Vlan-interface12] mpls enable [PE1-Vlan-interface12] mpls ldp enable [PE1-Vlan-interface12] quit
# Configure PE 1 to take PE 2 as an MP-IBGP peer.
[PE1] bgp 100 [PE1-bgp] peer 2.2.2.9 as-number 100 [PE1-bgp] peer 2.2.2.9 connect-interface loopback 0 [PE1-bgp] address-family vpnv6 [PE1-bgp-vpnv6] peer 2.2.2.9 enable [PE1-bgp-vpnv6] quit [PE1-bgp] quit
# Configure OSPF on PE 1.
[PE1] ospf 1 [PE1-ospf-1] area 0 [PE1-ospf-1-area-0.0.0.0] network 1.1.1.9 0.0.0.0 [PE1-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255 [PE1-ospf-1-area-0.0.0.0] quit [PE1-ospf-1] quit
# Configure basic MPLS and MPLS LDP on PE 2 to establish LDP LSPs.
<PE2> system-view [PE2] interface loopback 0 [PE2-LoopBack0] ip address 2.2.2.9 32 [PE2-LoopBack0] quit [PE2] mpls lsr-id 2.2.2.9 [PE2] mpls ldp [PE2-ldp] quit [PE2] interface vlan-interface 12 [PE2-Vlan-interface12] ip address 10.1.1.2 24 [PE2-Vlan-interface12] mpls enable [PE2-Vlan-interface12] mpls ldp enable [PE2-Vlan-interface12] quit
# Configure PE 2 to take PE 1 as an MP-IBGP peer.
[PE2] bgp 100 [PE2-bgp] peer 1.1.1.9 as-number 100 [PE2-bgp] peer 1.1.1.9 connect-interface loopback 0 [PE2-bgp] address-family vpnv6 [PE2-bgp-vpnv6] peer 1.1.1.9 enable [PE2-bgp-vpnv6] quit [PE2-bgp] quit
# Configure OSPF on PE 2.
[PE2] ospf 1 [PE2-ospf-1] area 0 [PE2-ospf-1-area-0.0.0.0] network 2.2.2.9 0.0.0.0 [PE2-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255 [PE2-ospf-1-area-0.0.0.0] quit [PE2-ospf-1] quit
Configure PEs to allow CE access:
# Configure PE 1.
[PE1] ip vpn-instance vpn1 [PE1-vpn-instance-vpn1] route-distinguisher 100:1 [PE1-vpn-instance-vpn1] vpn-target 1:1 [PE1-vpn-instance-vpn1] quit [PE1] interface vlan-interface 11 [PE1-Vlan-interface11] ip binding vpn-instance vpn1 [PE1-Vlan-interface11] ipv6 address 100::2 64 [PE1-Vlan-interface11] ospfv3 100 area 1 [PE1-Vlan-interface11] quit [PE1] ospfv3 100 [PE1-ospfv3-100] router-id 100.1.1.1 [PE1-ospfv3-100] domain-id 10 [PE1-ospfv3-100] quit [PE1] bgp 100 [PE1-bgp] ip vpn-instance vpn1 [PE1-bgp-vpn1] address-family ipv6 unicast [PE1-bgp-ipv6-vpn1] import-route ospfv3 100 [PE1-bgp-ipv6-vpn1] import-route direct [PE1-bgp-ipv6-vpn1] quit [PE1-bgp-vpn1] quit [PE1-bgp] quit
# Configure PE 2.
[PE2] ip vpn-instance vpn1 [PE2-vpn-instance-vpn1] route-distinguisher 100:2 [PE2-vpn-instance-vpn1] vpn-target 1:1 [PE2-vpn-instance-vpn1] quit [PE2] interface vlan-interface 11 [PE2-Vlan-interface11] ip binding vpn-instance vpn1 [PE2-Vlan-interface11] ipv6 address 120::2 64 [PE2-Vlan-interface11] ospfv3 100 area 1 [PE2-Vlan-interface11] quit [PE2] ospfv3 100 [PE2-ospfv3-100] router-id 120.1.1.1 [PE2-ospfv3-100] domain-id 10 [PE2-ospfv3-100] quit [PE2] bgp 100 [PE2-bgp] ip vpn-instance vpn1 [PE2-bgp-vpn1] address-family ipv6 unicast [PE2-bgp-ipv6-vpn1] import-route ospfv3 100 [PE2-bgp-ipv6-vpn1] import-route direct [PE2-bgp-ipv6-vpn1] quit [PE2-bgp-vpn1] quit [PE2-bgp] quit
# Execute the display ipv6 routing-table vpn-instance command on the PEs to verify that the path to the peer CE is along the OSPFv3 route across the customer networks, instead of the IPv6 BGP route across the backbone. (Details not shown.)
Configure a sham link:
# Configure PE 1.
[PE1] interface loopback 1 [PE1-LoopBack1] ip binding vpn-instance vpn1 [PE1-LoopBack1] ipv6 address 3::3 128 [PE1-LoopBack1] quit [PE1] ospfv3 100 [PE1-ospfv3-100] area 1 [PE1-ospfv3-100-area-0.0.0.1] sham-link 3::3 5::5 [PE1-ospfv3-100-area-0.0.0.1] quit [PE1-ospfv3-100] quit
# Configure PE 2.
[PE2] interface loopback 1 [PE2-LoopBack1] ip binding vpn-instance vpn1 [PE2-LoopBack1] ipv6 address 5::5 128 [PE2-LoopBack1] quit [PE2] ospfv3 100 [PE2-ospfv3-100] area 1 [PE2-ospfv3-100-area-0.0.0.1] sham-link 5::5 3::3 [PE2-ospfv3-100-area-0.0.0.1] quit [PE2-ospfv3-100] quit
Verifying the configuration
# Execute the display ipv6 routing-table vpn-instance command on the PEs to verify the following results (details not shown):
The path to the peer CE is now along the IPv6 BGP route across the backbone.
A route to the sham link destination address exists.
# Execute the display ipv6 routing-table command on the CEs to verify that the next hop of the OSPFv3 route to the peer CE is the VLAN interface connected to the PE. The VPN traffic to the peer is forwarded over the backbone. (Details not shown.)
# Verify that a sham link has been established on PEs. This example uses PE 1.
[PE1] display ospfv3 sham-link
OSPFv3 Process 100 with Router ID 100.1.1.1
Sham-link (Area: 0.0.0.1)
Neighbor ID State Instance ID Destination address
120.1.1.1 P-2-P 0 5::5
# Verify that the peer state is Full on PE 1.
[PE1] display ospfv3 sham-link verbose
OSPFv3 Process 100 with Router ID 100.1.1.1
Sham-link (Area: 0.0.0.1)
Source : 3::3
Destination : 5::5
Interface ID: 2147483649
Neighbor ID : 120.1.1.1, Neighbor state: Full
Cost: 1 State: P-2-P Type: Sham Instance ID: 0
Timers: Hello 10, Dead 40, Retransmit 5, Transmit delay 1
Request list: 0 Retransmit list: 0