L3 VPN Using L3 Tunnels or Native MPLS Example Configuration

This section steps you through both a L3 VPN using L3 tunneling and a L3 VPN using Native MPLS. Most steps in the L3 VPN configuration are the same for both L3 VPN types with the following exceptions:

• Native MPLS encapsulation using the mpls ip or mpls ipv6 commands is only enabled for L3 VPN using Native MPLS
• LDP and associated label commands are only configured for L3 VPN using Native MPLS
• L3 tunneling and associated static routes are only configured for L3 VPN using L3 tunneling

In our L3 VPN example we will configure two customers on three PE routers. Our example assumes that:

• VRFs are configured on the PE as shown in Layer 3 VPN using L3 Tunnels or Native MPLS Example (Virtual Routing and Forwarding (VRF) Configuration for VRF configuration details)
• Any interfaces connecting PE routers to directly connected CE routers are configured on the VRFs and interfaces to core routers are configured on the global VRF
• OSPF is configured on each VRF and redistributes the global BGP routes to the CEs using the redistribute bgp global command (Open Shortest Path First (OSPFv2) Configuration for IPv4 and Open Shortest Path First Version 3 (OSPFv3) Configuration for IPv6 OSPF configuration details)
• MPLS label mode will use the default (a single MPLS label is allocated for each VRF)
  

  Note

  This example uses the IPv4 address family. For IPv6 configurations:

  • Use IPv6 addressing
  • Enable MPLS encapsulation using the mpls ipv6 command, explicitly configuring the IPv6 transport address
  • Configure any required static routes using the ipv6 route command
  • If required, enable LDP using the mpls label-protocol-ldp ipv6 command
  • If LDP is required, explicitly set the LDP LSR ID using the mpls ldp-lsr-id command
  • Enable the VPNv6 BGP addressing family instead of VPNv4

Layer 3 VPN using L3 Tunnels or Native MPLS Example presents the basic configuration requirements for customer A (VPNA) and customer B (VPNB) on the three PE routers (Ignore L3 tunnel addressing when using Native MPLS).

Layer 3 VPN using L3 Tunnels or Native MPLS Example