Question 1,229 of 2,152

OSPF Troubleshooting (v2/v3) →mediumMultiple ChoiceObjective-mapped

300-410 OSPF Troubleshooting (v2/v3) Practice Question

This 300-410 practice question tests your understanding of ospf troubleshooting (v2/v3). 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 is troubleshooting OSPFv2 route redistribution. R1 is an ASBR redistributing static routes into OSPF. R2, an internal router, receives the redistributed routes but they appear as O E2 routes. However, R1 also has a directly connected network 10.1.1.0/24 that is not being advertised as an OSPF route. 'show ip ospf database external' on R2 shows the redistributed static routes but not the connected network. What is the most likely cause?

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.

Question 1mediummultiple choice

Review the full OSPF breakdown →

A
The connected network is not included in the redistribution because the engineer used 'redistribute static' without the 'subnets' keyword.
Why wrong: The 'subnets' keyword affects how classful networks are redistributed, but the connected network is not a static route, so it would not be redistributed by 'redistribute static' at all.
B
The connected network is not being advertised because it is not part of the OSPF process; the engineer must configure 'network 10.1.1.0 0.0.0.255 area 0' under router ospf.
Why wrong: That would make the connected network an internal OSPF route, not a redistributed route, but the question is about redistribution; however, the symptom is that the connected network is not in the OSPF database at all, so either method would work, but the most likely cause is that the ASBR is not redistributing connected routes.
C
The ASBR is missing the 'redistribute connected' command under the OSPF process.
Without 'redistribute connected', the directly connected network is not advertised into OSPF, even if the interface is enabled for OSPF (which it may not be).
D
The connected network is a loopback interface, and OSPF does not advertise loopback networks by default.
Why wrong: OSPF can advertise loopback interfaces if they are part of the OSPF process via network statements or redistribution.

Full breakdown with real-world context →

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 ASBR is missing the 'redistribute connected' command under the OSPF process.

By default, OSPF does not redistribute connected routes unless explicitly configured. The ASBR must use the 'redistribute connected' command under the OSPF process to advertise directly connected networks. The static routes are being redistributed because they are matched by the 'redistribute static' command, but the connected network is not part of the static route set unless it is also a static route. The engineer likely forgot to add 'redistribute connected' or use the 'subnets' keyword.

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 connected network is not included in the redistribution because the engineer used 'redistribute static' without the 'subnets' keyword.
Why it's wrong here
The 'subnets' keyword affects how classful networks are redistributed, but the connected network is not a static route, so it would not be redistributed by 'redistribute static' at all.
✗
The connected network is not being advertised because it is not part of the OSPF process; the engineer must configure 'network 10.1.1.0 0.0.0.255 area 0' under router ospf.
Why it's wrong here
That would make the connected network an internal OSPF route, not a redistributed route, but the question is about redistribution; however, the symptom is that the connected network is not in the OSPF database at all, so either method would work, but the most likely cause is that the ASBR is not redistributing connected routes.
✓
The ASBR is missing the 'redistribute connected' command under the OSPF process.
Why this is correct
Without 'redistribute connected', the directly connected network is not advertised into OSPF, even if the interface is enabled for OSPF (which it may not be).
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
OSPF neighbours must agree on key parameters.
✗
The connected network is a loopback interface, and OSPF does not advertise loopback networks by default.
Why it's wrong here
OSPF can advertise loopback interfaces if they are part of the OSPF process via network statements or redistribution.

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.

Trap categories for this question

Keyword trap
The 'subnets' keyword affects how classful networks are redistributed, but the connected network is not a static route, so it would not be redistributed by 'redistribute static' at all.

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.

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.

10 questions 20 questions 30 questions 50 questions Timed 30

300-410 practice-test guide →Study guide →Browse all practice tests

FAQ

Questions learners often ask

What does this 300-410 question test?

OSPF Troubleshooting (v2/v3) — This question tests OSPF Troubleshooting (v2/v3) — OSPF neighbours must agree on key parameters..

What is the correct answer to this question?

The correct answer is: The ASBR is missing the 'redistribute connected' command under the OSPF process. — By default, OSPF does not redistribute connected routes unless explicitly configured. The ASBR must use the 'redistribute connected' command under the OSPF process to advertise directly connected networks. The static routes are being redistributed because they are matched by the 'redistribute static' command, but the connected network is not part of the static route set unless it is also a static route. The engineer likely forgot to add 'redistribute connected' or use the 'subnets' keyword.

What should I do if I get this 300-410 question wrong?

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 →

How Courseiva writes practice questions · Editorial policy

Keep practising

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.

Loading comments…

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.