N10-009 DNS resolution Practice Question
A user reports that they can access a web server by its IP address (e.g., 10.10.10.50) but cannot access it by its domain name (e.g., server.example.com). The technician verifies that the DNS server is reachable and that the name resolves correctly from other workstations on the same subnet. Which of the following should the technician check NEXT?
⚠ Common exam trap
CompTIA often tests the distinction between connectivity issues (routing, firewall) and name resolution issues; the trap here is that candidates jump to checking the default gateway or firewall because they think 'can't reach the website,' but the symptom of IP working while domain fails points directly to the local DNS cache or resolver configuration.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Check the DNS cache on the user's workstation
The user's workstation can reach the web server by IP but not by domain name, while other workstations resolve the name correctly. This strongly suggests a local DNS resolution issue specific to that workstation, such as a corrupted or stale DNS cache. Flushing the DNS cache with `ipconfig /flushdns` is the logical next step before investigating broader network or firewall issues.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Check the DNS cache on the user's workstation
Why this is correct
A corrupted or stale DNS cache can prevent a client from resolving a name even though the DNS server is functional. Flushing the cache often resolves the issue.
- ✗
Verify the default gateway configuration
Why it's wrong here
Since the user can reach the server by IP address, the default gateway is working; the issue is name resolution, not routing.
When this WOULD be correct
A user cannot access any external websites or resources by IP or name, but internal resources work. The technician should verify the default gateway configuration to ensure the workstation can reach external networks.
- ✗
Renew the DHCP lease
Why it's wrong here
Renewing the DHCP lease would reassign IP configuration but would not directly affect DNS resolution if the workstation already has correct DNS server addresses.
When this WOULD be correct
A user cannot access any network resources after a network change. The technician finds the workstation has an APIPA address (169.254.x.x). Renewing the DHCP lease would obtain a valid IP from the DHCP server.
- ✗
Disable the Windows Firewall
Why it's wrong here
Firewall rules at the client could block DNS traffic, but since other users can resolve the name and the client can reach the DNS server, this is less likely than a local DNS cache issue.
When this WOULD be correct
A user cannot access any websites or network resources, and pinging by IP address fails. After verifying that the network cable is connected and the IP configuration is correct, the technician should check if the Windows Firewall is blocking all traffic.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The N10-009 exam frequently reuses these exact scenarios with slightly different constraints.
✓Check the DNS cache on the user's workstationCorrect answer▾
Why this is correct
A corrupted or stale DNS cache can prevent a client from resolving a name even though the DNS server is functional. Flushing the cache often resolves the issue.
✗Verify the default gateway configurationWrong answer — click to see why▾
Why this is wrong here
The issue is DNS resolution on a single workstation, not network connectivity. The default gateway is irrelevant because the user can already reach the web server by IP, indicating routing works.
★ When this WOULD be the correct answer
A user cannot access any external websites or resources by IP or name, but internal resources work. The technician should verify the default gateway configuration to ensure the workstation can reach external networks.
Why candidates choose this
Candidates may confuse DNS resolution failure with a general network connectivity problem, assuming the default gateway is misconfigured when the symptom is name resolution only.
✗Renew the DHCP leaseWrong answer — click to see why▾
Why this is wrong here
The issue is DNS resolution failure on a single workstation, not IP configuration. Renewing the DHCP lease would not fix a DNS cache problem, as the workstation already has a valid IP and can reach the server by IP.
★ When this WOULD be the correct answer
A user cannot access any network resources after a network change. The technician finds the workstation has an APIPA address (169.254.x.x). Renewing the DHCP lease would obtain a valid IP from the DHCP server.
Why candidates choose this
Candidates may think DHCP renewal refreshes all network settings, including DNS, and might assume the workstation has a stale or incorrect IP configuration causing the issue.
✗Disable the Windows FirewallWrong answer — click to see why▾
Why this is wrong here
Disabling the Windows Firewall is not the next step because the user can access the web server by IP address, indicating that the firewall is not blocking the traffic. The issue is name resolution, not connectivity.
★ When this WOULD be the correct answer
A user cannot access any websites or network resources, and pinging by IP address fails. After verifying that the network cable is connected and the IP configuration is correct, the technician should check if the Windows Firewall is blocking all traffic.
Why candidates choose this
Candidates often assume that any network issue is caused by the firewall, especially when symptoms like 'cannot access' appear, without considering that the problem is specific to name resolution rather than general connectivity.
Analysis generated from the official N10-009blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Visual reference
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About these practice questions
Courseiva writes every N10-009 question from scratch — 472 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This N10-009 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the N10-009 exam.