INTRO TO VRF
- VIRTUAL ROUTING AND FORWARDING (VRF) is used to DIVIDE a SINGLE ROUTER into MULTIPLE VIRTUAL ROUTERS
- Similar to how VLANs are used to divide a SINGLE SWITCH (LAN) into MULTIPLE VIRTUAL SWITCHES (VLANs)
- It does this by allowing a ROUTER to build MULTIPLE SEPARATE ROUTING TABLES
- INTERFACES (LAYER 3 only) and ROUTERS are configured to be in a specific VRF (aka VRF INSTANCE)
- ROUTER INTERFACES, SVIs and ROUTED PORTS on MULTILAYER SWITCHES can be configured in a VRF
- TRAFFIC in one VRF cannot be forwarded out of an INTERFACE in another VRF
- As an exception, VRF LEAKING can be configured to allow traffic to pass BETWEEN VRFs
- VRF is commonly used to facilitate MPLS (Multiple Protocol Label Switching)
- The kind of VRF we are talking about is VRF-Lite (VRF without MPLS)
- VRF is commonly used by SERVICE PROVIDERS to allow ONE DEVICE to carry traffic from MULTIPLE CUSTOMERS
- Each CUSTOMER’S TRAFFIC is isolated from the OUTSIDE
- CUSTOMER IP ADDRESSES can overlap without issue
VRF CONFIGURATION
Creation and Configuration of VRFs
How to show ip route
for VRFs
ping
other VRFs