The answer is that the route is an eBGP route, confirmed by the administrative distance of 20. This is because the default administrative distance for eBGP is 20, while iBGP routes default to 200; a distance of 20 directly identifies the route as external BGP. On the Cisco CCNP ENARSI 300-410 exam, this distinction tests your ability to interpret the `show ip route` output and differentiate between eBGP and iBGP paths, a common trap being that some candidates confuse the metric (0) with the distance. Remember that eBGP’s lower distance (20) makes it more preferred over iBGP (200) and many interior protocols, reflecting its role as a reliable path for external routes. A quick memory tip: “eBGP is 20, iBGP is 200—the extra zero means it’s internal and less preferred.”
300-410 Administrative Distance Practice Question
This 300-410 practice question tests your understanding of administrative distance. 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 R3:
R3# show ip route 172.16.1.0
Routing entry for 172.16.1.0/24
Known via "bgp 65000", distance 20, metric 0
Redistributing via bgp 65000
Last update from 192.168.1.1 00:00:15 ago
Routing Descriptor Blocks:
* 192.168.1.1, from 192.168.1.1, 00:00:15 ago
Route metric is 0, traffic share count is 1
Based on this output, what can be concluded about the administrative distance?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The route is an eBGP route, as the distance 20 is the default for eBGP.
The default administrative distance for BGP is 20 for eBGP routes and 200 for iBGP routes. A distance of 20 indicates this is an eBGP route. The metric of 0 is typical for eBGP routes.
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 route is an iBGP route with a manually configured distance of 20.
Why it's wrong here
The default distance for iBGP is 200, not 20. A distance of 20 indicates eBGP, not iBGP.
✓
The route is an eBGP route, as the distance 20 is the default for eBGP.
The output shows the route is known via BGP, not OSPF. The source protocol is BGP.
✗
The administrative distance of 20 is non-standard and must have been changed.
Why it's wrong here
20 is the standard default distance for eBGP routes, not a non-standard change.
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
Command / output trap
The output shows the route is known via BGP, not OSPF. The source protocol is BGP.
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.
Administrative Distance — This question tests Administrative Distance — OSPF neighbours must agree on key parameters..
What is the correct answer to this question?
The correct answer is: The route is an eBGP route, as the distance 20 is the default for eBGP. — The default administrative distance for BGP is 20 for eBGP routes and 200 for iBGP routes. A distance of 20 indicates this is an eBGP route. The metric of 0 is typical for eBGP routes.
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.
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 →
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.