You are a network engineer of a company that provides MPLS services to more customers. As shown below, Customer ABC has 2 offices running EIGRP with PE routers in both locations. Inside the MPLS core, you run OSPF and MP-BGP between PE routers and everything runs smoothly.


In order to increase the redundancy of the CORE network, your team desides to add a new link between PE-1 (Fa0/1) and P-4 (Fa0/0) routers.

You finish the change and you verify that the OSPF on the new link is established. You're also happy with the OSPF routing after the MPLS Core converges (for info: all links are equal cost). You also double-check-ed that the routing table for vrf VPNA did not change on both PE routers (it is same as in above picture).

PE-1#sh ip osp nei

Neighbor ID     Pri   State           Dead Time   Address         Interface           1   FULL/DR         00:00:33        FastEthernet0/1           1   FULL/DR         00:00:36        FastEthernet0/0

Soon after your change, you receive a ticket in which customer complains that connectivity between the two office is down:


Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:
Success rate is 0 percent (0/5)

What could be the wrong ?

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