Refer to the exhibit. An OSPF virtual link is configured. Based upon the show command output, why is the virtual-link down?
Router# show ip ospf virtual-links
Virtual Link OSPF_VL1 to router 209.165.202.101 is down
Run as demand circuit
DoNotAge LSA allowed.
Transit area 0, cost of using 65535
Transmit Delay is 1 sec, State DOWN,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
- The virtual interface VL1 is shut down.
- The timer intervals for virtual links need to be aggressive (2, 8, 8, and 1).
- Virtual links cannot transit area 0.
- The cost of the virtual link needs to be configured as 1.
Explanation: An OSPF virtual link is designed to provide a logical path to the backbone (Area 0) through a non-backbone area. The output shows the transit area is configured as Area 0, which is invalid because a virtual link cannot transit the backbone area itself; it must transit a normal non-backbone area.
Related exam: Checkpoint Exam: Layer 3 Technologies – OSPF
