- A
All interfaces except GigabitEthernet0/1 are passive and will not form EIGRP adjacencies.
Correct. The default passive setting applies to all interfaces, and the exception is made only for GigabitEthernet0/1.
- B
EIGRP hellos are sent on all interfaces, but GigabitEthernet0/1 is prevented from forming adjacencies.
Why wrong: Incorrect. The 'passive-interface default' command prevents hellos on all interfaces unless explicitly overridden.
- C
Only the network 10.0.0.0 is advertised, and all interfaces are passive.
Why wrong: Incorrect. The network statement and passive-interface commands are independent; the passive-interface command affects hello behavior, not network advertisement.
- D
EIGRP will only form adjacencies on interfaces with an IP address in the 10.0.0.0/8 range.
Why wrong: Incorrect. The passive-interface command does not filter based on network statements; it applies to all interfaces regardless of IP address.
Quick Answer
The correct answer is that all interfaces except GigabitEthernet0/1 are passive and will not form EIGRP adjacencies. This is because the passive-interface default command globally suppresses the sending of EIGRP hellos on every interface, effectively preventing neighbor discovery and adjacency formation across the entire router. The subsequent no passive-interface GigabitEthernet0/1 command acts as an explicit override, re-enabling hello transmission and adjacency formation only on that specific interface. On the ENCOR 350-401 exam, this configuration tests your understanding of the hierarchical override logic in EIGRP, where a global default can be selectively reversed per interface. A common trap is assuming that passive-interface default applies only to interfaces not covered by a network statement, but in reality it affects all interfaces regardless. A useful memory tip is to think of it as a "global lockdown with a single keyhole"—the default command locks all doors, and the no passive-interface command cuts the key for only the specified interface.
350-401 EIGRP Practice Question
This 350-401 practice question tests your understanding of eigrp. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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.
Consider the following EIGRP configuration on a Cisco IOS router:
router eigrp 100 network 10.0.0.0 passive-interface default no passive-interface GigabitEthernet0/1
What is the effect of this configuration?
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
All interfaces except GigabitEthernet0/1 are passive and will not form EIGRP adjacencies.
The 'passive-interface default' command sets all interfaces to passive by default, preventing them from sending EIGRP hellos and forming adjacencies. The 'no passive-interface GigabitEthernet0/1' command then overrides this default for that specific interface, allowing it to send hellos and form adjacencies. Therefore, only GigabitEthernet0/1 is active for EIGRP neighbor discovery, while all other interfaces remain passive.
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.
- ✓
All interfaces except GigabitEthernet0/1 are passive and will not form EIGRP adjacencies.
Why this is correct
Correct. The default passive setting applies to all interfaces, and the exception is made only for GigabitEthernet0/1.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
EIGRP hellos are sent on all interfaces, but GigabitEthernet0/1 is prevented from forming adjacencies.
Why it's wrong here
Incorrect. The 'passive-interface default' command prevents hellos on all interfaces unless explicitly overridden.
- ✗
Only the network 10.0.0.0 is advertised, and all interfaces are passive.
Why it's wrong here
Incorrect. The network statement and passive-interface commands are independent; the passive-interface command affects hello behavior, not network advertisement.
- ✗
EIGRP will only form adjacencies on interfaces with an IP address in the 10.0.0.0/8 range.
Why it's wrong here
Incorrect. The passive-interface command does not filter based on network statements; it applies to all interfaces regardless of IP address.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the interaction between 'passive-interface default' and 'no passive-interface' to see if candidates understand that the default command makes all interfaces passive, and the 'no' form selectively activates only the specified interface, rather than the reverse.
Trap categories for this question
Command / output trap
Incorrect. The 'passive-interface default' command prevents hellos on all interfaces unless explicitly overridden.
Detailed technical explanation
How to think about this question
Under the hood, the 'passive-interface default' command suppresses the sending of EIGRP hello packets on all interfaces, which prevents the formation of neighbor adjacencies and the exchange of routing information. The 'no passive-interface' command re-enables hello transmission on the specified interface, allowing EIGRP to discover neighbors and exchange routes. In real-world scenarios, this is commonly used to secure WAN links or loopbacks while allowing dynamic routing only on specific LAN interfaces, reducing unnecessary overhead and preventing routing loops.
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 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.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
EIGRP — study guide chapter
Learn the concepts, then practise the questions
- →
EIGRP practice questions
Targeted practice on this topic area only
- →
All 350-401 questions
2,015 questions across all exam domains
- →
ENCOR 350-401 study guide
Full concept coverage aligned to exam objectives
- →
350-401 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related 350-401 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Architecture practice questions
Practise 350-401 questions linked to Architecture.
Enterprise Network Design practice questions
Practise 350-401 questions linked to Enterprise Network Design.
SD-Access Architecture practice questions
Practise 350-401 questions linked to SD-Access Architecture.
SD-WAN Architecture practice questions
Practise 350-401 questions linked to SD-WAN Architecture.
QoS Architecture practice questions
Practise 350-401 questions linked to QoS Architecture.
Virtualization practice questions
Practise 350-401 questions linked to Virtualization.
Network Function Virtualization practice questions
Practise 350-401 questions linked to Network Function Virtualization.
Virtual Machines and Hypervisors practice questions
Practise 350-401 questions linked to Virtual Machines and Hypervisors.
VRF and Path Isolation practice questions
Practise 350-401 questions linked to VRF and Path Isolation.
Infrastructure practice questions
Practise 350-401 questions linked to Infrastructure.
OSPF practice questions
Practise 350-401 questions linked to OSPF.
BGP practice questions
Practise 350-401 questions linked to BGP.
Practice this exam
Start a free 350-401 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 350-401 question test?
EIGRP — This question tests EIGRP — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: All interfaces except GigabitEthernet0/1 are passive and will not form EIGRP adjacencies. — The 'passive-interface default' command sets all interfaces to passive by default, preventing them from sending EIGRP hellos and forming adjacencies. The 'no passive-interface GigabitEthernet0/1' command then overrides this default for that specific interface, allowing it to send hellos and form adjacencies. Therefore, only GigabitEthernet0/1 is active for EIGRP neighbor discovery, while all other interfaces remain passive.
What should I do if I get this 350-401 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 350-401 practice questions
- Drag and drop the steps to configure an extended access control list (ACL) on a Cisco router in the correct order.
- Drag and drop the steps to configure a site-to-site IPsec VPN on a Cisco router in the correct order.
- Drag and drop the steps to configure VLAN Trunking Protocol (VTP) on a Cisco switch in the correct order.
- Drag and drop the steps to configure a static route on a Cisco IOS router into the correct order.
- Drag and drop the steps to configure port security on a Cisco switch in the correct order.
- Drag and drop the steps for the Spanning Tree Protocol (STP) convergence process in the correct order.
Last reviewed: Jun 24, 2026
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.