The answer is that the DHCP server has detected IP address conflicts, meaning another device on the network is already using the same IP addresses. This is correct because the `show ip dhcp conflict` command reveals addresses the server has identified as already in use through detection methods like Ping and Gratuitous ARP; when the server pings an address or receives a Gratuitous ARP reply before offering it, it marks the IP as conflicting. On the Cisco CCNP ENARSI 300-410 exam, this output tests your ability to differentiate between a server that is working but encountering conflicts versus a server that has failed to allocate addresses—a common trap is confusing this with a DHCP pool exhaustion issue. The detection method column is key: Ping means the server probed the address and got a response, while Gratuitous ARP means a host replied to an ARP request for its own IP, both confirming a duplicate. Memory tip: think of “Ping and ARP” as the server’s “conflict cops” catching IP squatters.
300-410 DHCP (IPv4 and IPv6) Practice Question
This 300-410 practice question tests your understanding of dhcp (ipv4 and ipv6). Examine the command output carefully: the correct answer depends on what the output actually shows, not on general recall alone. 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 network engineer runs the following command on Router R1:
R1# show ip dhcp conflict
IP address Detection method Detection time VRF
192.168.1.20 Ping Mar 01 2020 01:00 AM
192.168.1.21 Gratuitous ARP Mar 01 2020 01:05 AM
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The DHCP server has detected IP address conflicts, meaning another device on the network is using the same IP addresses.
The `show ip dhcp conflict` command displays IP addresses that the DHCP server has detected as already in use on the network. The detection methods (Ping and Gratuitous ARP) confirm that another device is responding to these addresses, indicating a conflict. This output directly shows that the DHCP server is functioning but has identified conflicts, meaning another host is using the same IP addresses.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
The DHCP server is working normally; conflicts are automatically resolved.
Why it's wrong here
Conflicts are logged and prevent address assignment until cleared.
✓
The DHCP server has detected IP address conflicts, meaning another device on the network is using the same IP addresses.
Why this is correct
Conflicts indicate duplicate IP usage on the network.
Related concept
Read the scenario before looking for a memorised answer.
✗
The DHCP server is not responding to client requests.
Why it's wrong here
The output shows conflicts, not a lack of responses.
✗
The DHCP pool is misconfigured with overlapping subnets.
Why it's wrong here
Overlapping pools would not cause conflicts; conflicts are from external devices.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the distinction between a DHCP server that is working but detecting conflicts versus a server that is failing to respond or misconfigured, leading candidates to incorrectly assume the server is broken when it is actually performing its conflict detection duties correctly.
Trap categories for this question
Command / output trap
The output shows conflicts, not a lack of responses.
Detailed technical explanation
How to think about this question
The DHCP server performs conflict detection by sending a Ping (ICMP echo) to the candidate address and listening for a Gratuitous ARP reply from the client during the DHCPREQUEST phase (RFC 2131). If a response is received, the address is marked as conflicted and removed from the available pool until the administrator clears it or the lease expires. In real-world scenarios, this often occurs when static IPs are assigned within the DHCP scope or when rogue DHCP servers are present.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A network engineer segments a warehouse floor into three subnets: 20 scanners, 5 printers, and 2 management hosts. Picking the wrong mask wastes addresses or leaves too few usable hosts. Exam questions test whether you can apply CIDR notation, calculate block size, and identify the correct usable-host range for a given prefix.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this 300-410 question in full detail.
DHCP (IPv4 and IPv6) — This question tests DHCP (IPv4 and IPv6) — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The DHCP server has detected IP address conflicts, meaning another device on the network is using the same IP addresses. — The `show ip dhcp conflict` command displays IP addresses that the DHCP server has detected as already in use on the network. The detection methods (Ping and Gratuitous ARP) confirm that another device is responding to these addresses, indicating a conflict. This output directly shows that the DHCP server is functioning but has identified conflicts, meaning another host is using the same IP addresses.
What should I do if I get this 300-410 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
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 300-410 practice question is part of Courseiva's free Cisco 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 300-410 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.