The answer is that the path via 10.1.15.5 is chosen as best because it has a higher local preference of 200. In BGP best path selection, local preference is the second most significant attribute, evaluated immediately after weight; since both paths have the default weight of zero, the router compares local preference values, and the higher value wins. This output directly tests your understanding of the BGP best path selection local preference tiebreaker, a core concept for the Cisco CCNP ENARSI 300-410 exam where you must interpret show commands to identify why a specific path is preferred. A common trap is forgetting that local preference is evaluated before AS-path length or MED, so even a shorter AS-path with lower local preference would lose. Remember the mnemonic: We (weight) Love (local preference) Oranges (origin) As (AS-path) Special (MED) Treats (tiebreakers).
300-410 BGP Troubleshooting Practice Question
This 300-410 practice question tests your understanding of bgp troubleshooting. Examine the command output carefully: the correct answer depends on what the output actually shows, not on general recall alone. 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 runs the following command on Router R1:
R1# show bgp ipv4 unicast 10.3.3.0/24
BGP routing table entry for 10.3.3.0/24, version 10
Paths: (2 available, best #2, table default)
Advertised to update-groups:
1
Refresh Epoch 1
65003 65004
Based on this output, why is the path via 10.1.15.5 chosen as best?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "best"
Why it matters: Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Because it has a higher local preference of 200.
BGP selects the best path based on several criteria. Here, both paths are external, valid, and have the same weight (default 0). The path via 10.1.15.5 has a higher local preference (200 vs 100), which is the first tiebreaker after weight. Therefore, it is chosen as best.
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.
✗
Because it has a shorter AS path (65005 vs 65003 65004).
Why it's wrong here
AS path length is considered after local preference, but local preference is the deciding factor here.
✓
Because it has a higher local preference of 200.
Why this is correct
Local preference is compared before AS path length. The path with localpref 200 is preferred over 100.
Clue confirmation
The clue word "best" in the question point toward this answer.
Metrics are equal (0), so this does not determine the best path.
✗
Because it was learned from a lower neighbor IP address.
Why it's wrong here
Neighbor IP is a later tiebreaker and not needed here.
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.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this 300-410 question in full detail.
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.
BGP Troubleshooting — This question tests BGP Troubleshooting — OSPF neighbours must agree on key parameters..
What is the correct answer to this question?
The correct answer is: Because it has a higher local preference of 200. — BGP selects the best path based on several criteria. Here, both paths are external, valid, and have the same weight (default 0). The path via 10.1.15.5 has a higher local preference (200 vs 100), which is the first tiebreaker after weight. Therefore, it is chosen as best.
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: "best". Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
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 →
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A network engineer runs the following command to troubleshoot a BGP Troubleshooting issue:
R1# show bgp ipv4 unicast 192.168.1.0/24
BGP routing table entry for 192.168.1.0/24, version 12
Paths: (2 available, best #2, table default)
Advertised to update-groups:
1
Refresh Epoch 1
65001
10.1.1.2 from 10.1.1.2 (10.1.1.2)
Origin IGP, metric 0, localpref 100, valid, external, best
Refresh Epoch 2
65002
10.2.2.2 from 10.2.2.2 (10.2.2.2)
Origin IGP, metric 0, localpref 50, valid, external
What does this output indicate?
medium
A.Both paths are equally preferred, and BGP load-balances traffic to 192.168.1.0/24.
B.The path from AS 65002 is preferred because it has a lower local preference.
✓ C.The path from AS 65001 is the best path due to its higher local preference of 100.
D.The path from AS 65002 is the best path because it has a lower metric.
Why C: The show bgp ipv4 unicast command displays BGP paths for a specific prefix. Here, two paths are available: one from AS 65001 with local preference 100, and one from AS 65002 with local preference 50. The path with higher local preference (100) is selected as best.
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.
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.