CHAPT ER
36-1
Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
36
Configuring VRF-lite
Virtual Private Networks (VPNs) provide a secure way for customers to share bandwidth over an ISP
backbone network. A VPN is a collection of sites sharing a common routing table. A customer site is
connected to the service provider network by one or more interfaces, and the service provider associates
each interface with a VPN routing table. A VPN routing table is called a VPN routing/forwarding (VRF)
table.
With the VRF-lite feature, the Catalyst 4500 series switch supports multiple VPN routing/forwarding
instances in customer edge devices. (VRF-lite is also termed multi-VRF CE, or multi-VRF Customer
Edge Device). VRF-lite allows a service provider to support two or more VPNs with overlapping IP
addresses using one interface.
Note Starting with Cisco IOS Release 12.2(52)SG, the Catalyst 4500 switch supports VRF lite NSF support
with routing protocols OSPF/EIGRP/BGP.
Note The switch does not use Multiprotocol Label Switching (MPLS) to support VPNs. For information about
MPLS VRF, refer to the Cisco IOS Switching Services Configuration Guide at:
http://www.cisco.com/en/US/docs/ios/mpls/configuration/guide/mp_vpn_ipv4_ipv6_ps6922_TSD_Pro
ducts_Configuration_Guide_Chapter.html
Note For complete syntax and usage information for the switch commands used in this chapter, see the Cisco
Catalyst 4500 Series Switch Command Reference and related publications at this location:
http://www.cisco.com/en/US/products/hw/switches/ps4324/index.html
If the command is not found in the Cisco Catalyst 4500 Command Reference, you can locate it in the
larger Cisco IOS library. Refer to the Cisco IOS Command Reference and related publications at this
location:
http://www.cisco.com/en/US/products/ps6350/index.html
This chapter includes these topics:
About VRF-lite, page 36-2
Default VRF-lite Configuration, page 36-3