VRF Lite Notes
VRF Lite
– VRF without MPLS
– Causes problems if used on CE routers
The down-bit is set in OSPF update, so R4 drops the update.
Scenario -> One branch of the customer is using VRF lite with OSPF as the PE – CE protocol. The other branch is not using VRF.
Problem, the VRF branch will not accept any updates from the other branch because of the down-bit.
Solution #1
– Change the domain-id of any of the PE routers
-> Routes will get exchanged as type 5 LSAs, the routes being External 2
R1(config)# router ospf 10 vrf c1b1
domain-id 0.0.0.15
Domain-id -> preferable to “no router ospf 10 vrf c1b1”, “router ospf <new process-id> vrf c1b1”
Solution #2
– On the CE router, disable down-bit checking on the VRF
R4(config)# router ospf 1
capability vrf-lite
capability vrf-lite
– You are not a PE router, don’t check the down-bit
