Sample CompTIA Network+ N10-009 — 5.0 Network Troubleshooting questions with explanations
Use these examples to check how the topics are tested. Read the explanation for every option you were unsure about, then start a scored practice set above.
Question 1
3.0 Network Operations / 5.0 Network Troubleshooting
Which network documentation shows physical layout and connections?
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○ Logical network diagram
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○ Change log
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○ Cable map
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✓ Physical network diagram
Answer:
D. Physical network diagram
Physical network diagram: Shows physical layout and connections.
Question 2
5.0 Network Troubleshooting
Which cable issue is caused by two wires touching?
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○ Open
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○ Split pair
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○ EMI
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✓ Short
Answer:
D. Short
Short: Two wires touching.
Question 3
3.0 Network Operations / 5.0 Network Troubleshooting
Which network documentation records all network changes?
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✓ Change log
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○ Physical network diagram
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○ Logical network diagram
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○ Cable map
Answer:
A. Change log
Change log: Records all network changes.
Question 4
5.0 Network Troubleshooting
A remote user cannot connect to the corporate VPN. Other users can connect successfully. What should the technician check FIRST?
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○ Reboot the VPN server
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✓ Verify the user's credentials and VPN client configuration
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○ Replace the user's router
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○ Contact the ISP
Answer:
B. Verify the user's credentials and VPN client configuration
Since other users work, the server and ISP are fine. The user's specific credentials or client configuration is the most likely cause.
Question 5
3.0 Network Operations / 5.0 Network Troubleshooting
Which network documentation lists all hardware and software?
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✓ Asset inventory
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○ Cable map
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○ Change log
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○ Logical network diagram
Answer:
A. Asset inventory
Asset inventory: Lists all hardware and software.
Question 6
5.0 Network Troubleshooting
A user reports their workstation has no network connectivity. A technician tests the cable with a basic continuity tester and finds that pins 1 and 2 on one end show continuity with pins 3 and 6 on the other end. What is the MOST specific term for this type of cable fault?
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○ Open
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○ Short
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✓ Incorrect pinout
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○ Attenuation
Answer:
C. Incorrect pinout
The fault described is an incorrect pinout (C), specifically a sign of a miswired cable. In a standard T568A or T568B straight-through cable, pin 1 should connect to pin 1, pin 2 to pin 2, etc. The test shows pins are crossed (1 to 3, 2 to 6), which would prevent proper Ethernet communication. An open (A) means a break in the wire with no continuity. A short (B) means two wires are touching where they shouldn't. Attenuation (D) is signal loss over distance, which a basic continuity tester cannot measure.
Question 7
3.0 Network Operations / 5.0 Network Troubleshooting
Which network documentation shows ip addressing and vlans?
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○ Change log
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○ Cable map
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✓ Logical network diagram
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○ Physical network diagram
Answer:
C. Logical network diagram
Logical network diagram: Shows IP addressing and VLANs.
Question 8
5.0 Network Troubleshooting
Which command renews DHCP?
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○ ipconfig /all
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✓ ipconfig /renew
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○ ipconfig /release
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○ ipconfig /flushdns
Answer:
B. ipconfig /renew
ipconfig /renew is correct.
Question 9
3.0 Network Operations / 5.0 Network Troubleshooting
Which network documentation documents cable runs and labels?
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○ Change log
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○ Logical network diagram
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✓ Cable map
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○ Physical network diagram
Answer:
C. Cable map
Cable map: Documents cable runs and labels.
Question 10
5.0 Network Troubleshooting
Which command renews DHCP lease?
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○ ipconfig /flushdns
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○ ipconfig /all
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✓ ipconfig /renew
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○ ipconfig /release
Answer:
C. ipconfig /renew
ipconfig /renew is correct.
Question 11
5.0 Network Troubleshooting
Which command is used to clears dns resolver cache?
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○ ipconfig /renew
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✓ ipconfig /flushdns
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○ ipconfig /all
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○ tracert
Answer:
B. ipconfig /flushdns
ipconfig /flushdns: Clears DNS resolver cache.
Question 12
5.0 Network Troubleshooting
Which cable issue is caused by electromagnetic interference from motors/lights?
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○ Open
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○ Attenuation
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○ Crosstalk
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✓ EMI
Answer:
D. EMI
EMI: Electromagnetic interference from motors/lights.
Question 13
5.0 Network Troubleshooting
Which cable issue is electromagnetic interference?
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○ Short
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✓ EMI
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○ Attenuation
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○ Crosstalk
Answer:
B. EMI
EMI is correct. This concept is important for the certification exam and appears in scenario-based questions testing your understanding of when and how to apply it.
Question 14
5.0 Network Troubleshooting
A technician is sent to a wiring closet to trace a specific Cat 6 cable from a wall jack to its termination point on a patch panel among hundreds of cables. Which tool should the technician use FIRST to accomplish this task?
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○ Multimeter
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○ Cable tester
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✓ Tone generator and probe
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○ Protocol analyzer
Answer:
C. Tone generator and probe
A tone generator and probe (also called a fox and hound) is specifically designed to trace a single copper cable through walls, conduits, or patch panels by sending an audible tone. The technician would connect the tone generator to the wall jack and use the inductive probe to follow the tone to the correct termination point on the patch panel. A multimeter (A) can test for continuity or voltage but is inefficient for tracing. A cable tester (B) verifies cable integrity and pinout but does not help identify one cable among many. A protocol analyzer (D) examines network traffic, not physical cable paths.
Question 15
5.0 Network Troubleshooting
A technician is troubleshooting intermittent network drops on a copper Ethernet link. The cable passes a continuity test but the link sometimes fails, especially when devices such as motors or fluorescent lights are nearby. Which tool should the technician use to identify the source of the issue?
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✓ Spectrum analyzer
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○ Protocol analyzer
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○ Multimeter
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○ Tone generator
Answer:
A. Spectrum analyzer
A spectrum analyzer measures electromagnetic signals across a range of frequencies and can detect radio frequency interference (RFI) or electromagnetic interference (EMI) from nearby sources like motors or fluorescent lights. Protocol analyzers capture and inspect network traffic but cannot directly measure interference. A multimeter measures voltage, current, and resistance, which is useful for checking power or continuity but not for identifying RFI/EMI. A tone generator is used to trace cables by applying an audible signal, not for detecting interference. Since the symptoms suggest EMI/RFI causing intermittent drops, the spectrum analyzer is the best tool to identify the interfering source.
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