Question: Ping Doesn’t Work in a Simple Network

certskills
By certskills May 26, 2014 09:05

After reviewing this simple #CCNA question, I wondered if it was too difficult. But it’s a blog – we can always discuss the pieces. Today’s post has a multi-choice question about troubleshooting a seemingly simple problem: two hosts on the same switch, designed to be in the same VLAN, cannot ping each other. The interfaces are up/up – what’s wrong? Question is here today, answers in a few days.

The figure shows a simple small network in which all users should be in the same VLAN. A network engineer just connected to SW1’s console and issued a show interfaces command. The command lists a line status and line protocols status of “up” for both ports F0/7 and F0/8. However, when the user of host A issues a ping command listing host B’s IP address, the ping fails. Choose all answers which, if true, would definitely cause A to not be able to ping B?

A. F0/7 is configured to be in VLAN 2, and F0/8 has no configuration related to its VLAN assignment

B. Host A is configured with IP address 10.1.1.1, and host B is configured with IP address 10.2.2.2

C. A show interfaces vlan 1 command lists a line protocol of administratively down

D. Host A uses mask 255.255.255.0, and host B uses mask 255.255.255.128

E. Port security on SW1’s port F0/7 matches traffic from only one MAC address, namely host A’s MAC address

Answer: Switch Forwarding to Default Gateway
Answer: Ping Doesn't Work
certskills
By certskills May 26, 2014 09:05
Write a comment

8 Comments

  1. Luca May 26, 17:16

    hi,
    well, not sure whether I can accept A as answer as I have tried to put an port into an unassigned VLAN and it always go back to the default VLAN 1.
    Not really sure I can accept B, since no subnet mask is given so I am assuming is its default one 255.0.0.0.
    C is not acceptable and only line status can be administratively down …
    D is plausible, however, different subnets entails different default routers, and we know that both hosts were designed to be on the same VLAN(and subnet), the Host OS would have raised an exception at any network misconfig.
    E. should not be an impediment.

    Reply to this comment
  2. Peter Norcross May 27, 00:44

    If the answer is what I think it is, I don’t think it’s too tricky for CCNA. I wouldn’t be surprised if I saw something like this on the ICND2 (just passed back in March), but given my preparation for the CCNP, I would expect it more in the CCNP Switch exam. Again, that’s give that I’m getting the answer right :P.

    Reply to this comment
  3. M May 27, 15:26

    Answer is B and D

    Wrong answers.
    A : because question mentioned The figure shows a simple small network in which all users should be in the same VLAN.

    C : Quentin mentioned The command lists a line status and line protocols status of “up” for both ports F0/7 and F0/8. If theports are up than Vlan 1 should be up. By default al ports are member of Vlan1 by default.

    E : Port security never matches traffic based on mac address .

    Reply to this comment
  4. A May 28, 01:48

    Hi!

    Answer is B and D.

    Reply to this comment
  5. Just Me May 28, 02:13

    I’m thinking about an IP issue or an active firewall in Host B…:)

    Reply to this comment
  6. CCENTSkills May 28, 14:29

    See the ping back link for the answer/explanation…

    Reply to this comment
  7. AreNET October 7, 05:41

    A B C D

    Reply to this comment
View comments

Write a comment

Comment; Identify w/ Social Media or Email

Subscribe

Subscribe to our mailing list and get interesting stuff and updates to your email inbox.

Thank you for subscribing.

Something went wrong.

Search

Categories