OSPF Neighbours & Configuration

Covers Lesson 3 and Lesson 4

Checks that you can explain why two routers become adjacent, and configure OSPF so those adjacencies form on exactly the interfaces you intend.

Topics covered

• Link-state mechanics and the facts worth memorising
• What must match for an adjacency, and what need not
• The neighbour state machine and stuck states
• Network statements, wildcards, router-id, and passive-interface

Every question here is answerable from the first-party notes of the lessons above. You commit to an answer before you see whether it was right.

This quiz is a Week 5 milestone in its own right. Passing it does not change the completion state of any individual lesson, and you do not need it to finish the lessons it covers.

Section quiz

OSPF Neighbours & Configuration

8 questions covering Lesson 3 and Lesson 4. Answer each one before you see whether you were right.

Question 1 of 8

1. What distinguishes a link-state protocol like OSPF from a distance-vector protocol?

2. OSPF is carried directly on which protocol, and sends Hellos to which address?

3. Which of these must match for an OSPF adjacency to form?

4. R1 runs router ospf 1 and R2 runs router ospf 99. What happens?

5. Two routers on a point-to-point link flap between ExStart and Exchange and never reach Full, yet pings across the link succeed. What is the cause?

6. Which network statement enables OSPF on a /30 link addressed 10.1.12.0 in area 0?

7. What does passive-interface do to a LAN's OSPF participation?

8. You configure router-id 1.1.1.1 but show ip protocols still reports the old Router ID. What was missed?

Back to Lesson 4 Continue to Lesson 5

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