The correct conclusion is that the addresses 10.0.0.10 and 10.0.0.15 are unavailable for DHCP assignment. This is because the DHCP server on Router R6 has detected IP address conflicts for these two addresses—one via a ping probe and the other via a gratuitous ARP reply—and has marked them as conflicted in its database, preventing their reallocation until an administrator clears the entries. On the ENCOR 350-401 exam, DHCP conflict detection tests your understanding of how a Cisco router acting as a DHCP server verifies address uniqueness before and after leasing, using either a simple ICMP echo or a gratuitous ARP to detect a duplicate. A common trap is assuming the output shows active conflicts that are still being served, when in fact the server has already blacklisted these IPs. Remember the memory tip: “Ping probes before, ARP replies after” — ping is used to check before offering an address, while gratuitous ARP detects conflicts after the lease is active.
350-401 NAT and DHCP Practice Question
This 350-401 practice question tests your understanding of nat and dhcp. 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 R6:
R6# show ip dhcp conflict
IP address Detection method Detection time VRF
10.0.0.10 Ping Mar 01 2025 10:00 AM default
10.0.0.15 Gratuitous ARP Mar 01 2025 10:05 AM default
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The addresses 10.0.0.10 and 10.0.0.15 are unavailable for DHCP assignment.
The output shows two IP address conflicts detected by the DHCP server. One was detected via ping, the other via gratuitous ARP. These addresses are marked as conflicted and will not be assigned until resolved.
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 has successfully assigned these addresses to clients.
Why it's wrong here
Conflicted addresses are not assigned; they are removed from the pool.
✓
The addresses 10.0.0.10 and 10.0.0.15 are unavailable for DHCP assignment.
Why this is correct
Conflicted addresses are excluded from the pool until the conflict is cleared.
Related concept
Read the scenario before looking for a memorised answer.
✗
The DHCP server uses only ping to detect conflicts.
The conflicts were caused by the DHCP server itself.
Why it's wrong here
Conflicts indicate another device on the network is using the same IP.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Trap categories for this question
Command / output trap
Both ping and gratuitous ARP methods are shown.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
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.
Use explanations to understand the rule behind the answer.
TExam Day Tips
→Underline the problem statement mentally.
→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 practitioner preparing for the 350-401 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this 350-401 question in full detail.
Identify which 350-401 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
NAT and DHCP — This question tests NAT and DHCP — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The addresses 10.0.0.10 and 10.0.0.15 are unavailable for DHCP assignment. — The output shows two IP address conflicts detected by the DHCP server. One was detected via ping, the other via gratuitous ARP. These addresses are marked as conflicted and will not be assigned until resolved.
What should I do if I get this 350-401 question wrong?
Identify which 350-401 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
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 350-401 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 350-401 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.