VRF capability vrf-lite command
When a CE uses VRF lite, and when OSPF is used between PEs and CEs on an MPLS network, the capability vrf lite
command must be used on the CEs. This suppresses the PE checks needed to prevent loops when PE is performing a mutual redistribution between OSPF and BGP. Specifically, the DN bit generated by the CE is suppressed.
Links:
https://forum.networklessons.com/t/when-and-where-to-use-capability-vrf-lite/14877/2?u=lagapidis