The answer is a missing DNS server configuration. When a static IP address, subnet mask, and default gateway are manually set, the device can communicate locally because it knows how to reach other hosts on the same subnet, but without a DNS server address, it cannot translate domain names like google.com into IP addresses, which is why internet access by name fails. On the CompTIA A+ Core 1 220-1201 exam, this scenario tests your understanding of the difference between local connectivity and name resolution; a common trap is assuming the default gateway alone provides internet access, but it only handles routing, not domain lookups. Remember, static IP configuration requires you to manually enter all four critical values: IP, subnet, gateway, and DNS. A helpful memory tip is “No DNS, no names”—without that server address, your browser cannot find any website by its URL.
220-1201 Network Services Practice Question
This 220-1201 practice question tests your understanding of network services. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A user configures their laptop to use a static IP address, subnet mask, and default gateway. They can ping other devices on the same subnet but cannot reach the internet. What network service is most likely missing from their configuration?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
DNS server
With a static IP, the user must also configure a DNS server address to resolve domain names. Without DNS, they can communicate locally but cannot access internet resources by name. DHCP would auto-assign these settings, but static configuration requires manual entry.
Key principle: Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
DHCP server
Why it's wrong here
Since the user set a static IP, DHCP is not needed; the issue is likely DNS.
✓
DNS server
Why this is correct
Without a DNS server address, the laptop cannot resolve domain names, making internet access fail even with correct IP settings.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
NAT is a router function; the user's static configuration doesn't affect it, and local pings work, so NAT is likely fine.
✗
Proxy server
Why it's wrong here
A proxy is not required for basic internet access; DNS is the primary missing service.
Common exam traps
Common exam trap: usable hosts are not the same as total addresses
Subnetting questions often tempt you into counting all addresses. In normal IPv4 subnets, the network and broadcast addresses are not usable host addresses.
Detailed technical explanation
How to think about this question
Subnetting questions test whether you can identify the network, broadcast address, usable range, mask and correct subnet. Slow down enough to calculate the block size correctly.
KKey Concepts to Remember
CIDR notation defines the prefix length.
Block size helps identify subnet boundaries.
Network and broadcast addresses are not usable hosts in normal IPv4 subnets.
The required host count determines the smallest suitable subnet.
TExam Day Tips
→Write the block size before choosing the subnet.
→Check whether the question asks for hosts, subnets or a specific address range.
→Do not confuse /24, /25, /26 and /27 host counts.
Key takeaway
Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Real-world example
How this comes up in practice
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this 220-1201 question in full detail.
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related 220-1201 subnetting questions on CIDR, address ranges, and subnet selection.
Network Services — This question tests Network Services — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: DNS server — With a static IP, the user must also configure a DNS server address to resolve domain names. Without DNS, they can communicate locally but cannot access internet resources by name. DHCP would auto-assign these settings, but static configuration requires manual entry.
What should I do if I get this 220-1201 question wrong?
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related 220-1201 subnetting questions on CIDR, address ranges, and subnet selection.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
CIDR notation defines the prefix length.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This 220-1201 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 220-1201 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.