OcNOS DC : Layer 3 Guide : VRF Lite Configuration : VRF Configuration
VRF Configuration
Overview
Virtual routing and forwarding (VRF) is a technology that allows multiple instances of a routing table to co-exist within the same router at the same time. Because the routing instances are independent, the same or overlapping IP addresses can be used without conflicting with each other. VRF may be implemented in a network device by distinct routing tables known as forwarding information bases – one per routing instance.
Topology
Device topology
Default VRF
 
#con t
Enter the router configuration mode
(config)#interface eth1
Switch to interface eth1
(config-if)#ip address 3.3.3.2/24
Configure the ip address 3.3.3.2 to eth1
(config-if)#exit
Exit interface mode.
Adding a Static Route
 
#con t
Enter the router configuration mode
(config)#ip route 20.20.20.0/24 eth1
Add static route with eth1 as exit interface
User-Defined VRF
 
#con t
Enter configuration mode.
(config)#ip vrf vrf1
Create vrf1
(config)#exit
Exit configure mode.
(config)#interface eth1
Enter interface mode
(config-if)#ip vrf forwarding vrf1
Associate eth1 to vrf1.
(config-if)#ip address 3.3.3.2/24
Configure the IP address 3.3.3.2 to eth1
(config-if)#exit
Exit interface mode.
Adding a Static Route
 
#con t
Enter the router configuration mode
(config)# ip route vrf vrf1 20.20.20.0/24 eth1
Add static route in vrf1 with eth1 as exit interface
Validation
#show ip route vrf all
Codes: K - kernel, C - connected, S - static, R - RIP, B - BGP
O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2,
ia - IS-IS inter area, E - EVPN,
v - vrf leaked
* - candidate default
 
IP Route Table for VRF "default"
C 127.0.0.0/8 is directly connected, lo, 00:14:59
C 192.168.52.0/24 is directly connected, eth0, 00:14:55
IP Route Table for VRF "management"
IP Route Table for VRF "vrf1"
C 3.3.3.0/24 is directly connected, eth1, 00:00:44
S 20.20.20.0/24 [1/0] is directly connected, eth1, 00:00:08
 
Gateway of last resort is not set