Once a VRF routing instance is defined, it must be assigned to one or more virtual or physical interfaces on a PE.
To assign the VRF named VPN1 to Ethernet interface 0/1, enter the following commands.
device(config)# interface ethernet 0/1
device(config-if-e10000-0/1)# vrf forwarding VPN1
Syntax: [no] vrf forwarding vrf-name
The vrf-name variable is the name of the VPN that the interface is being assigned to.