CompTIA Network+ Network+ Network Troubleshooting Methodology 3 — Questions and Answers
Question 1: A technician suspects a duplex mismatch between a server NIC and a switch port. Which tool would BEST confirm this theory?
- Cable tester
- Protocol analyzer (Wireshark)
- Switch port statistics / management interface (Correct answer)
- Tone generator
Correct answer: Switch port statistics / management interface
The switch management interface shows current duplex and speed settings on each port, allowing direct comparison with the server NIC settings.
Question 2: Users in one VLAN cannot communicate with users in another VLAN despite both VLANs being configured on the same switch. What is the MOST likely missing component?
- A trunk port between switches
- An inter-VLAN routing device or Layer 3 switch (Correct answer)
- An additional access port
- A spanning tree configuration
Correct answer: An inter-VLAN routing device or Layer 3 switch
Inter-VLAN communication requires a router or Layer 3 switch to route traffic between VLANs; a Layer 2 switch alone cannot forward traffic across VLANs.
Question 3: A network technician receives multiple trouble tickets simultaneously. According to troubleshooting best practices, what should the technician do FIRST?
- Resolve the most complex ticket first
- Escalate all tickets to management
- Prioritize tickets by severity and business impact (Correct answer)
- Address tickets in the order they were received
Correct answer: Prioritize tickets by severity and business impact
Prioritizing by severity and business impact ensures the most critical services are restored first, minimizing organizational disruption.
Question 4: Which command would a technician use on a Windows workstation to display the current IP configuration including default gateway?
- ipconfig /all (Correct answer)
- netstat -r
- tracert /all
- ping /config
Correct answer: ipconfig /all
ipconfig /all displays full IP configuration details including IP address, subnet mask, default gateway, and DNS servers.
Question 5: A technician establishes that a user's laptop has a valid IP address, correct subnet mask, and correct default gateway, but still cannot reach external websites. What should the technician check NEXT?
- Physical cable connection
- DNS server configuration (Correct answer)
- MAC address table on the switch
- Spanning tree port state
Correct answer: DNS server configuration
With correct IP, mask, and gateway, an inability to reach websites by name points to a DNS resolution failure.
Question 6: After applying a fix, a technician wants to ensure the solution did not introduce new problems. Which step in the troubleshooting methodology addresses this?
- Identify the problem
- Establish a plan of action
- Verify full system functionality (Correct answer)
- Document findings
Correct answer: Verify full system functionality
Verifying full system functionality confirms the fix works and checks that no new issues were introduced by the change.
Question 7: A technician notices that two switches connected via fiber show link-down status despite the fiber cable appearing undamaged. What is the MOST useful next step?
- Replace both switches
- Use an optical power meter to measure signal loss on the fiber (Correct answer)
- Re-crimp the fiber connectors
- Check VLAN configuration on both switches
Correct answer: Use an optical power meter to measure signal loss on the fiber
An optical power meter measures signal loss (attenuation) on fiber links, identifying breaks, dirty connectors, or bend-radius violations not visible to the eye.
CompTIA Network+ Network+ Network Troubleshooting Methodology 3
A technician suspects a duplex mismatch between a server NIC and a switch port.
Which tool would BEST confirm this theory?