Module 8.6.3 Troubleshoot Common Network Problems Quiz Answers

Network Addressing and Basic Troubleshooting – Module 8.6.3 Troubleshoot Common Network Problems Quiz Answers

1. A user calls the help desk to report a workstation problem. Which three questions would produce the most helpful information for troubleshooting? (Choose three.)

If you received an error message, what was it?
What changes have you made to your workstation?
Do you have the warranty for your workstation?
What operating system version is running on your workstation?
Have you used a network monitoring tool on your workstation?
Have you performed a backup recently?

Explanation: In troubleshooting, the first step is to gather information related to the problem. One way to gather information is to ask questions of the individual who reported the problem as well as any other affected users. Questions should include end user experiences, observed symptoms, error messages, and information about recent configuration changes to devices or applications.

2. Users are complaining that they are unable to browse certain websites on the Internet. An administrator can successfully ping a web server via its IP address, but cannot browse to the domain name of the website. Which troubleshooting tool would be most useful in determining where the problem is?

netstat
tracert
nslookup
ipconfig

Explanation: The nslookup command can be used to look up information about a particular DNS name in the DNS server. The information includes the IP address of the DNS server being used as well as the IP address associated with the specified DNS name. This command can help verify the DNS that is used and if the domain name to IP address resolution works.

3. What are two common causes of a physical layer network connectivity problem? (Choose two.)

a monitor unplugged
an Ethernet cable plugged into a wrong port
an incorrect default gateway
an unassigned IP address
a faulty Ethernet cable

Explanation: An Ethernet cable plugged into a wrong port and a faulty Ethernet cable are two possible causes for physical network connectivity issues. An incorrect default gateway configuration and a lack of an IP address will cause logical connectivity issues.

4. The home computer of a user is working properly. However, the user cannot access the Internet. The Internet connection is provided through a cable company. The user cannot identify the cause of the problem. Who should the user contact for further help?

the operating system vendor
the help line of the cable company
the help line of the computer manufacturer
the support web site of the computer vendor

Explanation: Assuming the computer was working properly before, the most possible cause of the problem is the Internet connection provided by the cable company. Computer vendors and manufacturers cannot help because the computer is working properly.

5. Which troubleshooting method begins by examining cable connections and wiring issues?

top-down
bottom-up
substitution
divide-and-conquer

Explanation: In troubleshooting with the bottom-up method, a technician would start with the physical components of the network and move up through the layers of the OSI model until the cause of the problem is identified.

6. A user is unable to connect to the Internet. The network administrator decides to use the top-down troubleshooting approach. Which action should the administrator perform first?

Run the tracert command to identify the faulty device.
Check the patch cable connection from the PC to the wall.
Enter an IP address in the address bar of the web browser to determine if DNS has failed.
Run the ipconfig command to verify the IP address, subnet mask, and gateway on the PC.

Explanation: The top-down troubleshooting method starts with the applications and moves down through the layers of the OSI model until the cause of the problem is identified. Using a web brwoser to test DNS resolution is a troubleshooting step at the application layer.

7. If an administrator is troubleshooting a WLAN using a bottom up approach, which action would be taken first?

Update the firmware on the AP.
Make sure all devices are powered on.
Ping the AP.
Verify that the GUI interface is accessible from a client.

Explanation: Bottom up troubleshooting begins with the physical layer. Cables and power would be a logical place to begin the process. ICMP (ping) is a network layer utility. Channel settings are part of the client software. Firmware is the operating system software used by the AP.

8. A laptop cannot connect to a wireless access point. Which two troubleshooting steps should be taken first? (Choose two.)

Ensure that the wireless NIC is enabled.
Ensure that the laptop antenna is attached.
Ensure that the wireless SSID is chosen.
Ensure that the correct network media is selected.
Ensure that the NIC is configured for the proper frequency.

Explanation: A wireless laptop normally does not have an antenna attached unless a repair has recently been implemented. If the wireless NIC is enabled, the correct media, radio, will be used. When the NIC detects an access point, the correct frequency is automatically used.

9. For the second time in a week, workstations on a LAN are not able to log into a specific server. The technician fixed the problem the first time, but cannot remember the steps taken to solve it. What aspect of the troubleshooting process has the technician neglected?

identifying the problem
asking questions of end users
documenting the troubleshooting process
using structured techniques to solve a problem

Explanation: Proper documentation is a very important step in troubleshooting. The proper documentation can help troubleshoot the same or similar problems in the future.

10. A technician suspects that a new switch is the source of a network problem. While troubleshooting, the technician notices a blinking green activity LED on some of the ports. What does this indicate?

There are no cables plugged into the ports.
The power supply is the source of the problem.
The ports are operational and are receiving traffic.
The ports are operational, but no traffic is flowing.

Explanation: Most devices will have activity LEDs, which are often called link lights. A normal condition is for these LEDs to flash indicating that traffic is flowing through the port. A solid light typically indicates a device is plugged in, but no traffic is flowing. No light can indicate that nothing is plugged into the port, that there is no power to the device, or there is a cabling issue.

11. A customer called the cable company to report that the Internet connection is unstable. After trying several configuration changes, the technician decided to send the customer a new cable modem to try. What troubleshooting technique does this represent?

top-down
bottom-up
substitution
divide-and-conquer

Explanation: During troubleshooting, when the problem seems to be caused by a defective hardware, one approach is to replace the suspected hardware with a known good one. While not necessarily locating the problem, this technique can save time and quickly restore system functionality.

12. Which step should be taken next once a problem is resolved during a troubleshooting process?

Consult an FAQ.
Escalate the problem.
Update the documentation.
Run remote access software.

Explanation: Proper documentation can help troubleshoot the same or similar problems in the future. Proper documentation should include the type of error encountered, the steps taken to determine the cause of the problem, and the steps taken to correct the problem.

13. A technician installed a network adapter in a computer and wants to test network connectivity. The ping command can receive responses from workstations on the same subnet but not from remote workstations. What could be causing the problem?

The NIC driver is out of date.
The operating system is not compatible with the remote sites.
The TCP/IP protocol stack is not loaded.
The default gateway is incorrect.

Explanation: The default gateway is the interface IP address of the router that is connected to the local network. The function of the router is to enable communication among different networks. If the default gateway is not set or is incorrect, packets that are destined to other networks will not be able to reach the router, and hence there will be no communication to hosts that are located in other networks.