Monday, May 6, 2013

OSPF Problem 1

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Try to solve the lab problem in 10 minutes or less.

Enable OSPF in area 0 between router R1 and R2 on their point-to-point links (Se0/1).
  • Advertise Loopback0 address of both routers in area 0.
  • Use ‘network‘ command with the most specific wildcard mask to accomplish the task.


    Extra Credit
    Take as much time as you need to answer the following questions:

    1. What are the OSPF modes of operation available in Cisco® IOS™?
    2. Which OSPF modes are RFC-based and which are Cisco® proprietary?
    3. Which layer of OSI model would you classify OSPF to?
    4. OSPF creates three tables. What are these?
    5. What is OSPF LSDB?
    6. What does the ‘link-state’ in OSPF describe?
    7. What is OSPF hello packet and what is/are its purpose(s) in OSPF domain?
    8. What are the two link-local multicast addresses reserved for OSPF communication?
    9. What OSPF parameters must match in OSPF packet to establish full adjacency?
    10. What is the default destination address OSPF uses to send ‘hello’ packets on point-to-point links?
    11. What are the five packet types OSPF uses to communicate? What do they do?
    12. Which command would you use to verify OSPF-enabled interfaces (do not use ‘show run’)?
    13. Which command would you use to verify the state of the OSPF neighbor?
    14. What is a ‘router id’ in OSPF?
    15. How does OSPF selects its ‘router id’?
    16. Is OSPF ‘router id’ pre-emptive?
    17. Can you provide at least three commands to display OSPF router id (what are these)?
    18. What would happen if you tried to enable OSPF protocol in a router that has not a single IP address configured?
    19. Which command would you use to display LSDB?
    20. How many point-to-point links does an OSPF router advertise according to LSDB?
    21. What are the default timers (hello/dead) used on point-to-point links?
    22. What is/are other OSPF modes of operation that are compatible with the default one used on p2p links?
    23. What do you need to configure to make other mode(s) compatible with point-to-point mode?
    24. Which DBD parameter must match between OSPF neighbors to get past 2-way state?
    25. What is the type of LSA (name and number) that describes the links to other routers in the same area?
    26. Which command would you use to display LSDB entries about LSA type 1?
    27. In case of point-to-point OSPF mode, what does LSDB show as far as the following are concerned (assuming default ospf mode): link connected to, link id, link data?

    When you have solved the problem check the hint(s) below:

    Lab Hint
    • Does the ping from towards work?

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