CompTIA Network+ Network+ Network Troubleshooting Methodology 2 — Questions and Answers
Question 1: A technician is troubleshooting intermittent connectivity drops on a switch port. After checking cables and replacing them with known-good spares, the issue persists. What is the BEST next step?
- Replace the switch immediately
- Check the switch port statistics for errors and collisions (Correct answer)
- Reboot the connected workstation
- Contact the ISP
Correct answer: Check the switch port statistics for errors and collisions
Examining switch port statistics for errors, collisions, and CRC counts helps identify whether the problem is physical layer noise or a duplex mismatch.
Question 2: During troubleshooting, a technician confirms that a problem exists but cannot reproduce it consistently. Which troubleshooting step does this situation complicate most?
- Identify the problem
- Establish a theory of probable cause
- Test the theory (Correct answer)
- Implement the solution
Correct answer: Test the theory
Testing a theory requires reproducing the problem under controlled conditions; intermittent issues make it difficult to verify whether a proposed fix actually resolved the root cause.
Question 3: A user reports they can reach local network resources but cannot browse the internet. A ping to 8.8.8.8 fails, but pinging the default gateway succeeds. What is the MOST likely cause?
- Incorrect subnet mask on the workstation
- The default gateway is misconfigured or the upstream route is broken (Correct answer)
- The NIC is faulty
- DNS is not configured
Correct answer: The default gateway is misconfigured or the upstream route is broken
Successful gateway ping with failed external ping indicates routing beyond the gateway is broken, pointing to a misconfigured or unreachable upstream route.
Question 4: Which troubleshooting approach starts at the application layer and works toward the physical layer?
- Bottom-up approach
- Top-down approach (Correct answer)
- Divide and conquer approach
- Follow-the-path approach
Correct answer: Top-down approach
The top-down approach begins at Layer 7 (Application) and descends through the OSI model layers toward Layer 1 (Physical).
Question 5: After implementing a fix for a network issue, a technician verifies full functionality and then documents the solution. What critical step is MOST often skipped at this stage?
- Testing the fix
- Notifying affected users
- Identifying root cause
- Implementing preventive measures (Correct answer)
Correct answer: Implementing preventive measures
Implementing preventive measures—such as updating configurations, firewall rules, or monitoring thresholds—is frequently overlooked after a fix is confirmed working.
Question 6: A technician uses the divide-and-conquer troubleshooting method. On which OSI layer does this approach typically begin?
- Layer 1 – Physical
- Layer 3 – Network (Correct answer)
- Layer 7 – Application
- Layer 2 – Data Link
Correct answer: Layer 3 – Network
Divide and conquer typically starts at Layer 3 (Network) by testing IP connectivity, then moves up or down based on results.
Question 7: When a technician documents a resolved network incident, which detail is LEAST important to include?
- Root cause of the problem
- Steps taken to resolve the issue
- The technician's personal opinion of the network design (Correct answer)
- Changes made to prevent recurrence
Correct answer: The technician's personal opinion of the network design
Documentation should be objective and factual; personal opinions about network design are not relevant to incident records.
CompTIA Network+ Network+ Network Troubleshooting Methodology 2
A technician is troubleshooting intermittent connectivity drops on a switch port.
After checking cables and replacing them with known-good spares, the issue persists.
What is the BEST next step?