CompTIA N10-009 Sample Questions with Explanations

These original sample questions are designed to help you check how the exam topics appear in decision-style prompts. They are not taken from the live exam.

Use these sample questions as a guided self-assessment for CompTIA Network+ (N10-009) topics such as subnetting, switching, routing, wireless, services, troubleshooting, monitoring, and network security. The prompts emphasize practical network reasoning, not isolated acronym recall.

Where these questions fit in the N10-009 guide

The sample set below is part of the CompTIA N10-009 guide path:

• CompTIA certification hub
• N10-009 exam guide
• N10-009 cheat sheet
• N10-009 study plan
• N10-009 FAQ
• N10-009 resources
• N10-009 glossary

N10-009 networking sample questions

Work through each prompt before opening the explanation. Network+ questions usually reward a troubleshooting sequence that starts with scope, layer, and evidence.

Question 1

Topic: VLAN mismatch symptom

A user connects to a switch port and receives an IP address from the wrong subnet. Other users on nearby ports receive correct addresses. What should the network technician check first?

• A. The user’s monitor cable.
• B. The switch port VLAN assignment and any related port profile configuration.
• C. The DNS record for the company website.
• D. The printer toner level.

Best answer: B

Explanation: Getting an address from the wrong subnet often points to VLAN or switch port assignment. The fact that nearby ports work narrows the issue to this port’s configuration.

Why the other choices are weaker:

• A does not affect DHCP subnet assignment.
• C affects name resolution, not initial network placement.
• D is unrelated to network addressing.

What this tests: Mapping symptoms to switching and VLAN configuration.

Related topics: VLANs; Switch ports; DHCP; Troubleshooting

Question 2

Topic: DNS versus connectivity

A workstation can ping 8.8.8.8 but cannot browse to websites by name. Other devices on the same network browse normally. Which issue should the technician investigate first?

• A. The building’s power supply.
• B. The cable type between the monitor and PC.
• C. The workstation DNS configuration or name-resolution cache.
• D. The internet provider’s global routing table.

Best answer: C

Explanation: Successful ping to an IP address shows basic IP connectivity. Failure by name points first to DNS or local name-resolution settings, especially because other devices work.

Why the other choices are weaker:

• A would likely affect more than name resolution.
• B is unrelated to network name lookup.
• D is too broad and inconsistent with other devices working.

What this tests: Separating IP connectivity from DNS resolution during troubleshooting.

Related topics: DNS; Ping; Name resolution; Troubleshooting

Question 3

Topic: Wireless interference

Users in a conference room report poor wireless performance only when the room is full. Signal strength is acceptable, but retries and congestion increase sharply. What is the best next step?

• A. Replace the building router without checking wireless metrics.
• B. Disable encryption for all users.
• C. Change the IP address of the printer.
• D. Review channel utilization, client density, access point placement, and band steering or capacity options.

Best answer: D

Explanation: The symptom appears under high client density, so the next step is to inspect wireless capacity, channel use, retries, and AP placement rather than unrelated infrastructure.

Why the other choices are weaker:

• A is a broad replacement without evidence.
• B weakens security and does not solve congestion correctly.
• C is unrelated to room-wide Wi-Fi performance.

What this tests: Troubleshooting wireless performance by matching symptoms to RF and capacity factors.

Related topics: Wireless; Channel utilization; Client density; Performance

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