What is the influence of the Down bit on the OSPF route section process?
A.
OSPF routes with the Down bit set are never entered in the M-BGP routing table.
B.
OSPF routes with the Down but set are never entered in the backbone’s IGP routing table.
C.
OSPF routes with the Down bit set are passed up the hierarchical model.
They are blocked from being passed down the hierarchical model.
D.
OSPF routes with the Down bit set are marked as unavailable.
After the third consecutive update with the Down bit set, they are removed from the routing table.
Explanation:
Customer routes are NEVER entered into the core IGP in an MPLS environment. The down bit does not change this fact. What is does do instead is that it prevent routes redistributes from m-bgp to OSPF from being redistributed back into M-bgp. This makes A the correct answer