Glossary

Table Of Contents
Figure 176. VRF Network Example
VRF Configuration Notes
Although there is no restriction on the number of VLANs that can be assigned to a VRF instance, the total number of routes
supported in VRF is limited by the size of the IPv4 CAM.
VRF is implemented in a network device by using Forwarding Information Bases (FIBs).
A network device may have the ability to configure different virtual routers, where entries in the FIB that belong to one VRF
cannot be accessed by another VRF on the same device. Only Layer 3 interfaces can belong to a VRF. VRF is supported on
following types of interface:
Physical Ethernet interfaces
Port-channel interfaces (static & dynamic using LACP)
VLAN interfaces
Loopback interfaces
VRF supports route redistribution between routing protocols (including static routes) only when the routes are within the same
VRF.
uses both the VRF name and VRF ID to manage VRF instances. The VRF name and VRF ID number are assigned using the ip vrf
command. The VRF ID is displayed in show ip vrf command output.
The VRF ID is not exchanged between routers. VRF IDs are local to a router.
While using /32 route leak, do not use VLAN interface as Next-hop. This would result in packets being soft-forwarded by CPU,
which might lead to latency and packet drop.
If the next-hop IP in a static route VRF statement is VRRP IP of another VRF, this static route does not get installed on the
VRRP master.
VRF supports some routing protocols only on the default VRF (default-vrf) instance. Table 1 displays the software features
supported in VRF and whether they are supported on all VRF instances or only the default VRF.
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Virtual Routing and Forwarding (VRF)