DBS-C01 Monitoring and Troubleshooting Practice Question
A company runs an e-commerce platform using Amazon Aurora MySQL with Multi-AZ deployment. The application has a read-heavy workload and uses a mix of SELECT and UPDATE queries. Recently, the company migrated from a db.r5.large to a db.r5.2xlarge instance class to handle increased traffic. However, after the migration, the CPU utilization remains high during peak hours, and the application's page load times have increased. The DBA notices that the 'Read IOPS' metric is high, but the 'Read Latency' metric is low. There is also a high number of 'Select' queries in the database. The application uses a single database endpoint. What should the DBA do to reduce CPU utilization and improve read performance?
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
✓
Create one or more Aurora Replicas and modify the application to use read-only endpoints for SELECT queries.
Creating Aurora Replicas offloads read-only SELECT queries from the primary instance, reducing CPU utilization on the primary and improving overall read throughput. Option A is incorrect because enabling Multi-AZ with one standby replica provides high availability but does not help with read scaling; the standby is not used for reads. Option B is incorrect because Performance Insights is a monitoring tool that helps identify performance bottlenecks but does not directly reduce CPU utilization. Option C is incorrect because simply upgrading to a larger instance class may temporarily alleviate the issue but is not cost-effective and does not address the root cause of read-heavy workload imbalance; adding read replicas scales reads horizontally.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Enable Multi-AZ with one standby replica.
Why it's wrong here
Multi-AZ provides high availability, not read scaling.
- ✗
Enable Performance Insights and analyze the top SQL.
Why it's wrong here
Performance Insights helps identify issues, but does not directly reduce CPU.
- ✗
Upgrade the instance class to db.r5.4xlarge.
Why it's wrong here
Increasing instance size may not resolve the read-heavy bottleneck and increases cost.
- ✓
Create one or more Aurora Replicas and modify the application to use read-only endpoints for SELECT queries.
Why this is correct
Read replicas offload read traffic, reducing CPU on primary.
Go deeper
Related to this question
About these practice questions
This DBS-C01 question is part of Courseiva's 1,663-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DBS-C01 practice question is part of Courseiva's free Amazon Web Services 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 DBS-C01 exam.