This 200-901 practice question tests your understanding of network fundamentals. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. 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.
You are a network engineer at a financial services company. The network uses OSPF as the IGP, and all routers are in area 0. The core network consists of four routers (R1, R2, R3, R4) connected in a full mesh with GigabitEthernet links. The OSPF cost is set to 1 on all interfaces. Recently, a new application was deployed that requires low jitter and deterministic paths between two servers: Server A connected to R1 and Server B connected to R4. During peak hours, you notice that traffic between the servers is using the path R1->R3->R4 instead of R1->R2->R4, causing higher latency due to congestion on R3. OSPF metrics reflect equal cost to both paths (cost 2 each). You need to enforce that traffic from Server A to Server B always uses the path through R2 without changing the topology or adding additional hardware. Which action should you take?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "always"
Why it matters: Absolute qualifier. An answer using 'always' is only correct if there are genuinely no exceptions — absolute statements are often wrong in networking.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Increase the OSPF cost on the interface between R1 and R3 to a value higher than the cost of the path through R2.
Option D is correct because increasing the OSPF cost on the R1-R3 interface makes the path through R3 less preferred (cost >2), while the R1-R2-R4 path retains a total cost of 2. OSPF uses cost as its metric, and the lowest-cost path is installed in the routing table. By raising the cost on the R1-R3 link, you force traffic from Server A to Server B to take the deterministic path through R2 without changing the topology or adding hardware.
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.
✗
Change the routing protocol from OSPF to EIGRP to have better metric control.
Why it's wrong here
EIGRP also uses composite metrics; OSPF can already differentiate paths with cost.
✗
Use the 'default-information originate' command on R2 to attract traffic.
Why it's wrong here
This advertises a default route, not influencing specific prefixes.
✗
Configure policy-based routing (PBR) on R1 to send traffic destined to Server B's subnet to the next-hop R2.
Why it's wrong here
PBR is application-specific and may not be deterministic; also it can cause asymmetric routing issues.
✓
Increase the OSPF cost on the interface between R1 and R3 to a value higher than the cost of the path through R2.
Why this is correct
Increasing cost on R1-R3 makes the R1-R2-R4 path lower total cost (2 vs 1+10=11).
Clue confirmation
The clue word "always" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the misconception that PBR is required for path control when OSPF metrics can be easily tuned, leading candidates to overlook the simpler and more appropriate solution of adjusting interface cost.
Detailed technical explanation
How to think about this question
OSPF cost is derived from the reference bandwidth divided by interface bandwidth (default reference 100 Mbps), but can be manually set with the 'ip ospf cost' command. When costs are equal, OSPF performs equal-cost multipath (ECMP) load balancing; by making one path cost higher, the SPF algorithm selects only the lower-cost path. In real-world deployments, adjusting OSPF cost is a common traffic engineering technique to steer traffic away from congested links without altering the physical topology.
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.
Network Fundamentals — This question tests Network Fundamentals — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Increase the OSPF cost on the interface between R1 and R3 to a value higher than the cost of the path through R2. — Option D is correct because increasing the OSPF cost on the R1-R3 interface makes the path through R3 less preferred (cost >2), while the R1-R2-R4 path retains a total cost of 2. OSPF uses cost as its metric, and the lowest-cost path is installed in the routing table. By raising the cost on the R1-R3 link, you force traffic from Server A to Server B to take the deterministic path through R2 without changing the topology or adding hardware.
What should I do if I get this 200-901 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "always". Absolute qualifier. An answer using 'always' is only correct if there are genuinely no exceptions — absolute statements are often wrong in networking.
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 →
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 200-901 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 200-901 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.