- A
The policy blocks DHCPv6 server messages on Fa0/0 except from server 2001:db8::10.
The action is block, and server validation is enabled with a specific server list.
- B
The policy allows all DHCPv6 messages on Fa0/0 without any filtering.
Why wrong: The action is block, not allow.
- C
The policy only applies to DHCPv6 client messages and ignores server messages.
Why wrong: The policy blocks server messages, as indicated by server validation.
- D
The policy is inactive and not applied to any interface.
Why wrong: Status is Active, and Fa0/0 is listed as an untrusted port.
Question 736 of 2,152
300-410 IPv6 First Hop Security Practice Question
This 300-410 practice question tests your understanding of ipv6 first hop security. 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 to verify DHCPv6 guard policy:
R1# show ipv6 dhcp guard policy DHCP-POLICY
Policy: DHCP-POLICY Status: Active Device role: dhcp-client Trusted ports: none Untrusted ports: Fa0/0 DHCPv6 guard: enabled DHCPv6 guard action: block DHCPv6 server validation: enabled DHCPv6 server list: 2001:db8::10
What does this output indicate?
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
✓
The policy blocks DHCPv6 server messages on Fa0/0 except from server 2001:db8::10.
The output shows that DHCPv6 guard is enabled with an action of 'block' on untrusted port Fa0/0, and DHCPv6 server validation is enabled with a server list containing 2001:db8::10. This means the policy blocks DHCPv6 server messages (e.g., ADVERTISE, REPLY) received on Fa0/0, but allows them if they originate from the specified server address. Thus, only server messages from 2001:db8::10 are permitted, while all other DHCPv6 server messages are blocked.
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 policy blocks DHCPv6 server messages on Fa0/0 except from server 2001:db8::10.
Why this is correct
The action is block, and server validation is enabled with a specific server list.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
The policy allows all DHCPv6 messages on Fa0/0 without any filtering.
Why it's wrong here
The action is block, not allow.
- ✗
The policy only applies to DHCPv6 client messages and ignores server messages.
Why it's wrong here
The policy blocks server messages, as indicated by server validation.
- ✗
The policy is inactive and not applied to any interface.
Why it's wrong here
Status is Active, and Fa0/0 is listed as an untrusted port.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the distinction between the 'device role' (dhcp-client vs. dhcp-server) and the filtering direction; the trap here is assuming that 'dhcp-client' role means the policy filters client messages, when in fact it filters server messages on that port to protect clients from rogue servers.
Detailed technical explanation
How to think about this question
DHCPv6 guard is a First Hop Security feature that prevents rogue DHCPv6 servers by filtering server messages on untrusted ports. The 'dhcp-client' device role indicates the port is expected to have only DHCPv6 clients, so server messages are blocked unless they match the server list. The server validation uses the source address of the DHCPv6 server message (typically the link-local or global address in the server list) to permit only trusted servers, which is critical in mitigating DHCPv6 spoofing attacks in enterprise networks.
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 security administrator must allow nursing staff to reach a patient records server while blocking access from the guest Wi-Fi VLAN. After applying an extended ACL, traffic is still blocked from nursing workstations. The ACL was applied outbound instead of inbound on the wrong interface. Questions like this test ACL direction and placement rules.
Visual reference
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
IPv6 First Hop Security — study guide chapter
Learn the concepts, then practise the questions
- →
IPv6 First Hop Security practice questions
Targeted practice on this topic area only
- →
All 300-410 questions
2,152 questions across all exam domains
- →
Cisco CCNP ENARSI 300-410 study guide
Full concept coverage aligned to exam objectives
- →
300-410 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related 300-410 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Layer 3 Technologies practice questions
Practise 300-410 questions linked to Layer 3 Technologies.
EIGRP Troubleshooting practice questions
Practise 300-410 questions linked to EIGRP Troubleshooting.
OSPF Troubleshooting (v2/v3) practice questions
Practise 300-410 questions linked to OSPF Troubleshooting (v2/v3).
BGP Troubleshooting practice questions
Practise 300-410 questions linked to BGP Troubleshooting.
Route Redistribution practice questions
Practise 300-410 questions linked to Route Redistribution.
Policy-Based Routing (PBR) practice questions
Practise 300-410 questions linked to Policy-Based Routing (PBR).
VRF-Lite practice questions
Practise 300-410 questions linked to VRF-Lite.
Route Maps and Route Filtering practice questions
Practise 300-410 questions linked to Route Maps and Route Filtering.
Administrative Distance practice questions
Practise 300-410 questions linked to Administrative Distance.
Route Summarization practice questions
Practise 300-410 questions linked to Route Summarization.
Bidirectional Forwarding Detection (BFD) practice questions
Practise 300-410 questions linked to Bidirectional Forwarding Detection (BFD).
VPN Technologies practice questions
Practise 300-410 questions linked to VPN Technologies.
Practice this exam
Start a free 300-410 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this 300-410 question test?
IPv6 First Hop Security — This question tests IPv6 First Hop Security — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The policy blocks DHCPv6 server messages on Fa0/0 except from server 2001:db8::10. — The output shows that DHCPv6 guard is enabled with an action of 'block' on untrusted port Fa0/0, and DHCPv6 server validation is enabled with a server list containing 2001:db8::10. This means the policy blocks DHCPv6 server messages (e.g., ADVERTISE, REPLY) received on Fa0/0, but allows them if they originate from the specified server address. Thus, only server messages from 2001:db8::10 are permitted, while all other DHCPv6 server messages are blocked.
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 →
Keep practising
More 300-410 practice questions
- Drag and drop the steps to negotiate an IKEv2 IPsec site-to-site tunnel into the correct order, from first to last.
- Drag and drop the steps to troubleshoot an IPsec site-to-site VPN adjacency failure into the correct order, from first t…
- Drag and drop the steps to verify and validate the operational state of an IPsec site-to-site VPN into the correct order…
- Consider the following configuration snippet: ip cef ! interface GigabitEthernet0/0 ip address 10.0.0.1 255.255.255.25…
- A router is configured with 'logging host 10.1.1.100' and 'logging trap informational'. The engineer notices that syslog…
- Drag and drop the steps to configure a GRE tunnel for IPv6 over IPv4 into the correct order, from first to last.
Last reviewed: Jul 4, 2026
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.