300-410 Layer 3 Technologies Practice Question
A network engineer is configuring EIGRP on a router. The engineer wants to ensure that the router does not send EIGRP updates out of an interface connected to a non-EIGRP neighbor, but still advertises the connected network into EIGRP. Which configuration command should be used?
⚠ Common exam trap
The trap here is thinking that a distribute-list or split horizon can prevent EIGRP updates from being sent, when they do not stop hello packets or adjacency formation.
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
✓
passive-interface <interface> under router EIGRP configuration
The passive-interface command under EIGRP configuration stops EIGRP from sending hellos and updates on the specified interface, preventing adjacency formation with non-EIGRP neighbors. Meanwhile, the connected network is still advertised into EIGRP if it falls under a network statement. Other options either do not prevent updates or also stop advertisement of the network.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
passive-interface <interface> under router EIGRP configuration
Why this is correct
The 'passive-interface' command under EIGRP configuration suppresses EIGRP hello packets and updates on the specified interface, preventing adjacency formation. However, the connected network is still advertised into EIGRP as long as it is covered by a network statement. This meets the requirement of not sending updates out of the interface while still advertising the subnet.
- ✗
no network <network> under router EIGRP configuration
Why it's wrong here
Removing the network statement would stop EIGRP from advertising the connected network and also stop EIGRP from running on the interface. This would prevent updates, but it would also prevent the network from being advertised into EIGRP, which is not desired. The engineer wants to still advertise the connected network, so this is incorrect.
- ✗
distribute-list <acl> out <interface> under router EIGRP configuration
Why it's wrong here
A distribute-list outbound filters EIGRP routing updates sent out an interface. While it can prevent certain routes from being advertised, it does not stop EIGRP hello packets or prevent adjacency formation. The interface would still send hellos and potentially form an adjacency. Additionally, the connected network might still be advertised if permitted by the ACL. This does not meet the requirement of preventing updates to a non-EIGRP neighbor.
- ✗
ip split-horizon under interface configuration
Why it's wrong here
Split horizon prevents a router from advertising a route back out the same interface through which it was learned. It does not prevent EIGRP updates from being sent out an interface to a non-EIGRP neighbor. In fact, split horizon is enabled by default on most interfaces and does not stop hellos or adjacency formation. It is not the correct tool for this requirement.
Quick reference
Routing Protocol Comparison
| Protocol | Metric | Max Hops | Algorithm | Type |
|---|---|---|---|---|
| RIP v2 | Hop count | 15 | Bellman-Ford | Distance vector |
| OSPF | Cost (bandwidth) | Unlimited | Dijkstra (SPF) | Link state |
| EIGRP | Composite metric | Unlimited | DUAL | Hybrid |
| IS-IS | Cost | Unlimited | Dijkstra | Link state |
| BGP | Policy / attributes | Unlimited | Path vector | Path vector |
RIP's 15-hop limit makes it unsuitable for large networks. OSPF and EIGRP dominate modern enterprise deployments.
Go deeper
Related to this question
About these practice questions
Courseiva writes every 300-410 question from scratch — 1,401 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 and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Cisco exam blueprint
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.