- A
The hub's 'next-hop-self' command is configured under the BGP neighbor statement for the spoke, but the route reflector behavior overrides it, causing the hub to not modify the next-hop for routes reflected between spokes.
In a route reflector setup, 'next-hop-self' must be configured under the address-family for the neighbor; otherwise, the reflector does not change the next-hop for reflected routes.
- B
The spokes are not configured as route-reflector clients, so the hub does not reflect routes between them, and the next-hop remains unchanged.
Why wrong: If the spokes are not clients, the hub does not reflect routes; but the symptom is that spokes receive routes from other spokes, indicating reflection is happening.
- C
The iBGP session between hub and spokes is using loopback interfaces, and the next-hop is set to the loopback IP, which is not reachable via the tunnel.
Why wrong: If loopbacks are used, the next-hop would be the loopback IP, but the issue here is that the next-hop is the hub's tunnel IP, not a loopback.
- D
The 'next-hop-self' command is only applicable for eBGP sessions, not iBGP, so it has no effect on the reflected routes.
Why wrong: 'next-hop-self' works for both eBGP and iBGP; it is commonly used in iBGP to ensure reachability.
Quick Answer
The answer is that the hub’s route reflector behavior overrides the next-hop-self command for reflected routes between spokes. When a hub acts as a route reflector in a DMVPN, it reflects routes from one spoke to another without altering the next-hop attribute by default, even if next-hop-self is configured under the neighbor statement for the spoke. This is because the route reflector function only modifies the next-hop for routes it originates or receives from non-client peers, not for routes reflected between its clients. On the Cisco CCNP ENARSI 300-410 exam, this tests your understanding of the interaction between iBGP route reflection and the next-hop-self command in a DMVPN Phase 2 or 3 topology, where spoke-to-spoke reachability depends on NHRP shortcuts or proper next-hop manipulation. A common trap is assuming next-hop-self applies universally, but it must be explicitly configured under the address-family for route-reflector clients to take effect. Memory tip: “Reflectors reflect, they don’t redirect—next-hop-self must be explicit for client-to-client paths.”
300-410 DMVPN Practice Question
This 300-410 practice question tests your understanding of dmvpn. 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 network engineer configures iBGP between DMVPN hub and spokes using the hub as a route reflector. On the hub, the BGP configuration includes 'neighbor <spoke-ip> next-hop-self'. Unexpectedly, spokes receive routes from other spokes with the next-hop set to the hub's tunnel IP, but the spokes cannot reach that next-hop because it is not in their routing table. Which is the most likely explanation?
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 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 hub's 'next-hop-self' command is configured under the BGP neighbor statement for the spoke, but the route reflector behavior overrides it, causing the hub to not modify the next-hop for routes reflected between spokes.
In a DMVPN Phase 2 or 3 network, the hub typically sets the next-hop to itself using 'next-hop-self' for routes advertised to spokes. However, if the hub is a route reflector, it does not change the next-hop for routes received from one spoke and advertised to another spoke, unless 'next-hop-self' is explicitly configured. The corner case is that 'next-hop-self' must be applied under the address-family or neighbor configuration, and if it is misapplied or missing for the route-reflector client sessions, the spoke-to-spoke routes retain the original next-hop (the other spoke's tunnel IP), which may not be reachable if NHRP redirect or shortcuts are not enabled.
Key principle: OSPF neighbour adjacency depends on matching area, hello/dead timers, network type, and authentication — IP reachability alone is not enough.
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 hub's 'next-hop-self' command is configured under the BGP neighbor statement for the spoke, but the route reflector behavior overrides it, causing the hub to not modify the next-hop for routes reflected between spokes.
Why this is correct
In a route reflector setup, 'next-hop-self' must be configured under the address-family for the neighbor; otherwise, the reflector does not change the next-hop for reflected routes.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
OSPF neighbours must agree on key parameters.
- ✗
The spokes are not configured as route-reflector clients, so the hub does not reflect routes between them, and the next-hop remains unchanged.
Why it's wrong here
If the spokes are not clients, the hub does not reflect routes; but the symptom is that spokes receive routes from other spokes, indicating reflection is happening.
- ✗
The iBGP session between hub and spokes is using loopback interfaces, and the next-hop is set to the loopback IP, which is not reachable via the tunnel.
Why it's wrong here
If loopbacks are used, the next-hop would be the loopback IP, but the issue here is that the next-hop is the hub's tunnel IP, not a loopback.
- ✗
The 'next-hop-self' command is only applicable for eBGP sessions, not iBGP, so it has no effect on the reflected routes.
Why it's wrong here
'next-hop-self' works for both eBGP and iBGP; it is commonly used in iBGP to ensure reachability.
Common exam traps
Common exam trap: OSPF can fail even when IP connectivity looks correct
OSPF neighbour formation depends on matching areas, timers, network type, authentication and passive-interface behaviour. Do not choose an answer only because the devices can ping.
Detailed technical explanation
How to think about this question
OSPF questions usually test the details that control adjacency and route selection. Read the neighbour state, area, router ID and interface configuration before deciding what is wrong.
KKey Concepts to Remember
- OSPF neighbours must agree on key parameters.
- Router ID selection can affect neighbour relationships and LSDB output.
- OSPF cost influences the preferred path.
- A route can appear in OSPF information but not become the installed route.
TExam Day Tips
- Check area mismatch first when OSPF adjacency fails.
- Review passive interfaces when a network is advertised but no neighbour forms.
- Use show ip ospf neighbor and show ip route clues carefully.
Key takeaway
OSPF neighbour adjacency depends on matching area, hello/dead timers, network type, and authentication — IP reachability alone is not enough.
Real-world example
How this comes up in practice
A network engineer at a university connects two campus buildings via a fibre link. Both routers run OSPF, but no adjacency forms — even though both routers can ping each other. The engineer finds one router is in area 0 and the other in area 1. OSPF adjacency requires matching area numbers, hello/dead timers, and network type. IP reachability alone is not enough.
What to study next
Got this wrong? Here's your next step.
Review OSPF neighbour requirements — matching area type, hello and dead timers, network type, stub flags, and authentication. Study show ip ospf neighbor states (INIT, 2-WAY, FULL). Then practise related 300-410 OSPF questions on adjacency and route selection.
- →
DMVPN — study guide chapter
Learn the concepts, then practise the questions
- →
DMVPN 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?
DMVPN — This question tests DMVPN — OSPF neighbours must agree on key parameters..
What is the correct answer to this question?
The correct answer is: The hub's 'next-hop-self' command is configured under the BGP neighbor statement for the spoke, but the route reflector behavior overrides it, causing the hub to not modify the next-hop for routes reflected between spokes. — In a DMVPN Phase 2 or 3 network, the hub typically sets the next-hop to itself using 'next-hop-self' for routes advertised to spokes. However, if the hub is a route reflector, it does not change the next-hop for routes received from one spoke and advertised to another spoke, unless 'next-hop-self' is explicitly configured. The corner case is that 'next-hop-self' must be applied under the address-family or neighbor configuration, and if it is misapplied or missing for the route-reflector client sessions, the spoke-to-spoke routes retain the original next-hop (the other spoke's tunnel IP), which may not be reachable if NHRP redirect or shortcuts are not enabled.
What should I do if I get this 300-410 question wrong?
Review OSPF neighbour requirements — matching area type, hello and dead timers, network type, stub flags, and authentication. Study show ip ospf neighbor states (INIT, 2-WAY, FULL). Then practise related 300-410 OSPF questions on adjacency and route 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?
OSPF neighbours must agree on key parameters.
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 →
Last reviewed: Jun 18, 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.