hardMultiple ChoiceObjective-mapped
300-410 Practice Question: An engineer is troubleshooting a DMVPN phase 3…
An engineer is troubleshooting a DMVPN phase 3 network where spoke-to-spoke tunnels are established, but traffic between spokes is taking a suboptimal path through the hub. The engineer checks 'show ip nhrp shortcut' on the spoke and sees no shortcut entries. The hub has 'ip nhrp redirect' enabled, and the spoke has 'ip nhrp shortcut' enabled. The engineer also verifies that the spoke's routing table has a route to the remote spoke's LAN via the hub. What is the most likely cause?
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 router does not have a route to the remote spoke's LAN subnet.
In DMVPN phase 3, for spoke-to-spoke shortcuts to be installed, the spoke must receive an NHRP redirect from the hub. If the hub does not send a redirect, the spoke will not create a shortcut. The hub sends a redirect only if it has a route to the destination subnet. If the hub does not have a route to the remote spoke's LAN, it will not send a redirect.
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 router does not have a route to the remote spoke's LAN subnet.
Why this is correct
Correct because the hub must have a route to the destination subnet to send an NHRP redirect.
- ✗
The spoke's 'ip nhrp shortcut' command is missing on the tunnel interface.
Why it's wrong here
Incorrect because the engineer verified that 'ip nhrp shortcut' is enabled.
- ✗
The spoke's routing table has a static route to the remote spoke's LAN via the hub.
Why it's wrong here
Incorrect because a static route would not prevent shortcut creation; the redirect is still needed.
- ✗
The hub's tunnel interface has 'no ip nhrp redirect' configured.
Why it's wrong here
Incorrect because the engineer verified that 'ip nhrp redirect' is enabled.
Visual reference
Go deeper
Related to this question
Learn chapter
Introduction to ENARSI Exam and Network Fundamentals
Key term
DMVPN Phase 2
DMVPN Phase 2 is an advanced Cisco routing technology that allows spoke routers to communicate directly with one another without sending traffic through a central hub, using dynamic routing protocols and multipoint GRE tunnels.
Key term
DMVPN Phase 3
DMVPN Phase 3 is a Cisco networking technology that allows branch offices to connect directly to each other without always going through a central hub, but with smarter routing that lets the hub control the traffic paths more efficiently.
About these practice questions
Courseiva writes every 300-410 question from scratch — 1,966 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
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.