Reference Guide

Virtual Routing and Forwarding (VRF) | 1033
• On a switch port on which multiple VLANs are assigned to different VRFs, the source MAC address
in packets routed on a VRF may not be the same as the MAC address distributed in ARP requests. As
a result, security applications running on neighboring routers that check the source MAC address in
incoming packets may find that the address does not match the ARP-learned MAC address.
• You can assign a static ARP only to a VLAN that is mapped to the default VRF (0) instance.
• By default, all VLANs (4096) are associated with the default VRF until you reassign them to a
non-default VRF with the
ip vrf forwarding command. You can assign up to 4096 VLANs to a
non-default VRF instance.
• VLANs used with VRF must be Layer 3 VLANs. Layer 2 VLANs can be configured for non-VRF use.
Refer to the VLAN chapter for complete information.
• All VLAN member ports must be removed from a VLAN that you move from one VRF instance to
another.
View VRF instance information
To display information about VRF configuration, enter the show ip vrf command.
Connect an OSPF process to a VRF instance
OSPF routes are supported on all VRF instances. Refer to Chapter 35, Open Shortest Path First (OSPFv2
and OSPFv3) for complete OSPF configuration information.
Assign an OSPF process to a VRF instance . Return to CONFIGURATION mode to enable the OSPF
process. The OSPF Process ID is the identifying number assigned to the OSPF process, and the Router ID
is the IP address associated with the OSPF process..
Once the OSPF process and the VRF are tied together, the OSPF Process ID cannot be used again in the
system.
Task Command Syntax Command Mode
Assign an interface to a VRF instance.
ip vrf forwarding vrf-name INTERFACE
Task Command Syntax Command Mode
Display the interfaces assigned to a VRF instance.
To display information on all VRF instances (including the default
VRF 0), do not enter a value for vrf-name.
show ip vrf [vrf-name] EXEC
Task Command Syntax Command Mode
Enable the OSPFv2 process globally for a VRF instance.
Enter the VRF key word and instance name to tie the OSPF instance to the
VRF. All network commands under this OSPF instance are subsequently
tied to the VRF instance
.
process-id range: 0-65535
router ospf process-id vrf
vrf name
CONFIGURATION