Default Vrf-Lite Configuration - Cisco 4500M Software Manual

Chapter 28 Configuring VRF-lite
This is the packet-forwarding process in a VRF-lite CE-enabled network as shown in
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To configure VRF, create a VRF table and specify the Layer 3 interface associated with the VRF. Then
configure the routing protocols in the VPN and between the CE and the PE. BGP is the preferred routing
protocol used to distribute VPN routing information across the provider's backbone. The VRF-lite
network has three major components:
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Default VRF-lite Configuration

Table 28-1
Table 28-1 Default VRF Configuration
Feature
VRF
Maps
VRF maximum routes
Forwarding table
OL-6696-01
When the CE receives a packet from a VPN, it looks up the routing table based on the input interface.
When a route is found, the CE forwards the packet to the PE.
When the ingress PE receives a packet from the CE, it performs a VRF lookup. When a route is
found, the router adds a corresponding MPLS label to the packet and sends it to the MPLS network.
When an egress PE receives a packet from the network, it strips the label and uses the label to
identify the correct VPN routing table. Then the egress PE performs the normal route lookup. When
a route is found, it forwards the packet to the correct adjacency.
When a CE receives a packet from an egress PE, it uses the input interface to look up the correct
VPN routing table. If a route is found, the CE forwards the packet within the VPN.
VPN route target communities—Lists of all other members of a VPN community. You need to
configure VPN route targets for each VPN community member.
Multiprotocol BGP peering of VPN community PE routers—Propagates VRF reachability
information to all members of a VPN community. You need to configure BGP peering in all PE
routers within a VPN community.
VPN forwarding—Transports all traffic between all VPN community members across a VPN
service-provider network.
shows the default VRF configuration.
Default Setting
Disabled. No VRFs are defined.
No import maps, export maps, or route maps are defined.
None.
The default for an interface is the global routing table.
Software Configuration Guide—Release 12.2(25)EW
Default VRF-lite Configuration
Figure 28-1:
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