Home > ICND2 – OSPF Hotspot

ICND2 – OSPF Hotspot

April 20th, 2015 in ICND2 200-101 Go to comments

Note: If you are not sure about OSPF, please read my OSPF tutorial first.

Question

This item contains several questions that you must answer. You can view these questions by clicking on the corresponding button to the left. Changing questions can be accomplished by clicking the numbers to the left of each question. In order to complete the questions, you will need to refer to the topology.
To gain access to the topology, click on the topology button at the bottom of the screen. When you have finished viewing the topology, you can return to your questions by clicking on the Questions button to the left.

Each of the windows can be minimized by clicking on the [-]. You can also reposition a window by dragging it by the title bar.

OSPF_message.jpg

Question 1

Explanation

The Router ID (RID) is an IP address used to identify the router and is chosen using the following sequence:

+ The highest IP address assigned to a loopback (logical) interface.
+ If a loopback interface is not defined, the highest IP address of all active router’s physical interfaces will be chosen.
+ The router ID can be manually assigned

In this case, because a loopback interface is not configured so the highest active IP address 192.168.0.1 is chosen as the router ID.

Question 2

Explanation

HELLO messages are used to maintain adjacent neighbors so even when the network is converged, hellos are still exchanged. On broadcast and point-to-point links, the default is 10 seconds, on NBMA the default is 30 seconds.

Although OSPF is a link-state protocol but the full database from each router is sent every 30 minutes (not seconds) -> C and D are not correct.

Question 3

Question 4

Question 5

Explanation

Although OSPF is configured using default classful addressing but OSPF is a link-state routing protocol so it will always send the subnet mask of each network in their advertised routes. Therefore R1 will learn the the complete subnets. Four networks list below will be in the routing table of R1:
+ 172.16.2.64/30
+ 172.16.2.228/30
+ 172.16.2.232/30
+ 172.16.3.0/24

Note: Other networks will be learned as “Directly connected” networks (marked with letter “C”)

Comments (63) Comments
  1. Router47
    October 19th, 2013

    Why are Question 4’s answers C and F?

    Where did the four networks come from as the answer in Question 5?

  2. Router47
    October 22nd, 2013

    please explain the answers for Question # 3

    also, aren’t the the 4 addresses pertaining to Question # 5 CLASS B addresses?
    so then why do they have classless subnet masks when the question clearly says OSPF is configured using default CLASSFUL addressing?

  3. jp.ccna
    October 24th, 2013

    On question 4, the answers are D and F, Not C and F. For OSPF, routers have to be in the same area to form adjacency. Also the timers must be the same.

    For question 5, for dynamic routing, routers learn about any networks NOT directly connected via a routing protocol (in this case, OSPF). The trick is realizing that R3’s and R4’s connection to the same switch is going to the SAME network. Initial instinct may tell you to count those connections as 2 networks if you didn’t notice the IP addresses.

    For #3, OSPF doesn’t support load balancing across unequal cost paths, so changing the cost, or changing the bandwidth (which will affect cost since it is the default metric for OSPF) will cause the redundant links to be unequal.

    As far as the CLASSFULL addressing for question 5, because all addresses are the same class (Class B in this case), this is considered a classfull network. By definition, though, this is wrong. Classfull networks should use the default subnet mask. Classless networks are subnetted. For example, RIP V1 is classful as it can ONLY use the default subnet masks with it’s networks and RIP V2 is considered classless as the networks can be subnetted.

  4. Val
    November 29th, 2013

    I guess that Q4 is incorrect at all because R1 will never be able to establish an OSPF neighbour relationship with R3, since R1 and R3 must both sit on the same data link to be the neighbours. According to the exhibit R1 and R3 do not share the same data link.

  5. Jeol
    December 8th, 2013

    Val, you are right! “OSPF neighbors are routers that both use OSPF and both sit on the same data link.” – 100-101 Official Cert Guide by Wendell.
    And this can help https://learningnetwork.cisco.com/thread/2010
    the right question may be like that:
    R1 is unable to establish an Adjacent OSPF neighbors relationship with R3 for exchange LSA. What are possible reasons for this problem?
    I may be wrong about explanation and my suggestion about right question, but original question from that page is definitely wrong.

  6. kjk
    December 20th, 2013

    Q4 would still be wrong…LSAs are sent to directly connected neighbors who then forward on the LSAs to its directly connected neighbors…@Jeol, given your suggetion, the problem would be with R2 if R3 wasn’t recieving any LSAs regarding R1s directly connected networks.
    My opinion is either the question or the diagram is incorrect–they just don’t go together.

    OPSF neighbors must agree on the Hello and Dead time intervals, the network type as well as the OSPF Area.

  7. kjk
    December 20th, 2013

    …that is to be neighbors…

  8. CCENT someday
    January 20th, 2014

    OSPF Troubleshooting:

    show ip ospf neighbor

    show ip int brief

    sho ip osfp int brief

    show ip ospf

    https://www.youtube.com/watch?v=9hQoqa-jItg

  9. CCENT Someday
    January 31st, 2014

    Anyone,

    I plan on taking exam next week. What other sims/labs did you get besides the OSPF 6 router?

    Thanks in Advance!

  10. John
    April 27th, 2014

    The flash test for this section incorrectly displays the answers for question 3 on question 4.

  11. 9tut
    April 28th, 2014

    @John: Thanks for your detection. We fixed it!

  12. Justin Reply Please
    May 10th, 2014

    Has anyone seen this question in the ICND 2? 200-101 ?

  13. Manohar Tn
    May 16th, 2014

    Got 986/1000 Marks, {5/16/2014} 50 Questions, Ospf Sim, Security simlet, and Router and switch Simlet Was also there…..All questions From 9tut. and Examcollections…..Now Heading For Icnd2 And Blogging…..

    For Any Help.
    Manohar Tn
    Website: http://www.techlinko.com
    G+ : https://plus.google.com/u/0/+ManoharTN9/

  14. ss
    July 17th, 2014

    this s for ccna 100-101 200-101

  15. Sam
    September 4th, 2014

    SOMEBODY PLS TELL ME IF ACLs ARE NOT INCLUDED IN ICND1?

  16. Emmanouel
    September 27th, 2014

    To:Sam

    ACL’s are inicluded in ICND1

  17. joseph
    October 1st, 2014

    question #1. how do you tell that the loop back interfaces are disabled?
    thanks

  18. shersam
    October 8th, 2014

    is it the latest exam questions or not ……
    and what is the reliability of answers thanks for your effort

  19. GeoCes
    October 14th, 2014

    Diagram shows R1 S0/0/1 as IP address .255 on a network 172.16.2.224/30. Not sure how that is going to work. More than likely R1 S0/0/1 should be .225…

  20. Gabbie
    October 17th, 2014

    Hi everyone! I’m taking the ICND1 this Monday,I’m a bit nervous tho,any dumps would be appreciated! gfedejko@yahoo.com

  21. Tony
    October 19th, 2014

    Can someone please send me the data dump for ICND1? I am taking the exam next week! acordero2@me.com Thanks!

  22. Ali
    November 3rd, 2014

    Question 4 confuses me. i think R1 & R3 shouldn’t form neighbor relationships in the first place because they are not in the same data link network, nor they are connected by a serial connection. SOMEONE PLEASE EXPLAIN.

  23. Tebogo
    November 11th, 2014

    hi guys I need help am writing on the 18 ICND1 kindly assist with the recent dumps tebogobareng@yahoo.com that will be highly appreciated

  24. Mncedisi
    November 15th, 2014

    Thank you! thank you! 9tut I have made it today final a score of 881 and every question I have learn from this site were there pls stick with all the question and sims from this site.

  25. shubham
    November 24th, 2014

    tommorow is my 100-101 exam……….

  26. dfgg
    January 6th, 2015

    gdfgfd

  27. India
    January 12th, 2015

    hello india I am from when you see exam I will know that before it is in when it is for study purpose so it will be more easy today. hope this helps

  28. Vic
    January 25th, 2015

    @Ali. You are correct in the fact that if you type #show cdp neighbors, R3 will not see
    R4. He will see Sw-A, for cdp works at the data link layer. Ospf has a different neighbor than
    Cdp. Ospf send hello packets on multicast address to form neighbor relationships,
    And switch forwards those multicast addresses. Ospf routers form neighbor relationships
    On both serial and ethernet. Serial makes a point to point, and ethernet makes multiacces

  29. anonny
    February 5th, 2015

    Judging from dumps I get the feeling that this question/simlet is actually in ICND2 ?

  30. Hello
    June 9th, 2015

    Question 1: I’m asking the same question that joseph asked. How do you tell if the loopback interfaces are disabled from the diagram ?
    I believe the answer should be C since 172.16.2.1 is the highest loopback address configured on R1 and the question does not state the status of the loopback interface.
    Please advice

  31. Gondo
    June 9th, 2015

    @ Hello . We have four interfaces S0/0/0 , s0/0/1 , F0/0 , F0/1 … F0/1 is using ip 172.16.2.1 , We do no have any loop back interfaces (Lo), So loop back interfaces are out of the picture.

  32. Hello
    June 10th, 2015

    @Gondo. thank you very much for clarifying this for me. I saw the symbol of a loopback interface without reading the interface label. Thanks again.

  33. Phil
    June 19th, 2015

    Q2: Unless I am missing something I believe the explanation for Q2 – “Although OSPF is a link-state protocol but the full database from each router is sent every 30 minutes ” is incorrect since databases are only sent to the DR/BDR. In this diagram we don’t know router priorities and therefore we don’t know which routers would be elected the DR and BDR. We cannot therefore say that databases will be exchanged between R3 and R4.

    Any comments?

  34. kaaba
    June 20th, 2015

    I have this lab/question on my ICND2 19.06.2015!

  35. Samosa4Life
    July 6th, 2015

    @Camnyc: please you may i know if you can share your license with me now?

    Thank you in advance.

  36. 9tut
    July 13th, 2015

    @all: We had to move all the questions and answers out of 9tut. We can only keep the explanation. You can download the questions and answers at: https://mega.co.nz/#!oIdESYbD!yyu33vygrfKPy4rcmcbV6qW2fxINNoTokuDM3CjA_og

  37. anon
    July 17th, 2015

    I got this question in ICND2

  38. anon
    July 17th, 2015

    @9tut i still see all the Q and A.. what are you talking about?

  39. Anon D
    July 27th, 2015

    Would someone be kind enough to explain question 5 please?

    (1) Why will 4 networks be in the routing table?
    (2) Why would 172.16.2.0/27 and 72.16.1.0/27 NOT be in the routing table for R1.
    (3) Why will 192.168.0.0/30 and 172.16.2.224/30 NOT be in the routing table for R1? (Is it because they are directly connected?)

    This might be basic questions, but I am still trying to understand OSPF.

    Thank you very much.

  40. DC3000
    July 27th, 2015

    @Anon D
    Guys correct me if I’m wrong..
    1.
    172.16.2.64/30 – R2
    172.16.2.228/30 – R2
    172.16.2.232/20 – R2
    172.16.3.0/24 – R3 and R4
    All learned via ospf

    2. Directly connected
    3. Directly connected

  41. Anon D
    July 27th, 2015

    Thank you DC3000.

    Would someone be able to point me to a link stating why it is that directly connected networks are not included in the routing table. To me, it is saying that I cannot reach a directly connected route because it is not in the routing table.

    Thanks again.

  42. Anon
    July 29th, 2015

    This question should be included in the ICND2 list as well – got this today – passed with 986

  43. Surferdude
    July 31st, 2015

    Can someone explain Question # 3 plz
    To allow or prevent load balancing to network 172.16.3.0/24, which of the following commands could be used in R2? (Choose two)

  44. Anonymous
    August 6th, 2015

    @Anon

    It is in the routing table, it is just labeled as C for connected versus L for learned.

  45. Anonymous
    September 5th, 2015

    This lab sim included in latest ICND 200-101? tnx

  46. FooF
    December 6th, 2015

    yes this lab is in 200-101 exam

  47. kric1991
    February 8th, 2016

    I am a Premium member here, could somebody send me the latest Dump questions for the ICND2 questions? You could send it to {email not allowed}

    Thanks
    – K

  48. Anonymous
    February 14th, 2016

    So what exactly are the benefits of using one area with OSPF? Ive been hearing its a new question on the test, but Ive only seen one answer that its easier to configure OSPF. Whats the other reason? Ive tried looking it up, but cant find it.

  49. Anonymous
    April 4th, 2016

    Another reason is, to reduce the routing table which means a router with less recursive lookups / less load on the CPU

  50. mike
    May 12th, 2016

    i had this one today ICND2 …. 986/1000
    all from 9tut…
    no ipv6

  51. nervousGirl
    May 16th, 2016

    is this lab in ICND1 exam?
    i see it on the questions 9tut posted in the icnd1 section

  52. Black Ranger
    May 20th, 2016

    @nervousgirl is in ICND2

  53. Estudiante
    June 5th, 2016

    Where can i find the QUESTION TO ICND2 in pdf?

  54. Anonymous
    June 13th, 2016

    Had Q’s 1, 2, 3, 5 today. Easy day!!

  55. anonymous2
    July 23rd, 2016

    Q1 and Q5 appeared in OSPF hotspot y’day

  56. Anon69
    July 30th, 2016

    i had this one this week on ICND2 ….

  57. Tom
    August 17th, 2016

    Where is the OSPF Hotspot simulation? I am also a premium member.

  58. binay
    August 18th, 2016

    I didn’t find the ospf topology button at then end of this page as you have said in question.. please help.. i am also a premium member.

  59. ahed
    August 21st, 2016

    Try this website question look same

    http://www.9tut.net/icnd2/ospf-questions/comment-page-1

  60. PS
    August 31st, 2016

    @Anon69: Hi there, Is this questions still valid in icnd 2 ,200-101 exam???

  61. Deli
    September 21st, 2016

    As for the benefits of using single area OSPF are
    1. Simpler to configure.
    2. Less LSA types on the network.

  62. Anonymous
    September 22nd, 2016

    Today pass the ICND2, thank you 9tut.net…

  63. anon
    February 23rd, 2017

    i cannot view the questions, only the text question 3 or question 4 show u and there is nothing listed underneath them. Can someone help me resolve this