DOP-C02 Exam Dumps : AWS Certified DevOps Engineer - Professional

The correct answer is A.

Option A is correct because it meets the requirements with the most operational efficiency. Updating the ecommerce application to emit a JSON object to a CloudWatch log group for each processed transaction is a simple and cost-effective way to collect the data needed for the dashboard. Using CloudWatch Logs Insights to query the log group and to visualize the results in a pie chart format is also a convenient and integrated solution that leverages the existing CloudWatch dashboards. Attaching the results to the desired CloudWatch dashboard is straightforward and does not require any additional steps or services.

Option B is incorrect because it introduces unnecessary complexity and cost. Updating the ecommerce application to emit a JSON object to an Amazon S3 bucket for each processed transaction is a valid way to store the data, but it requires creating and managing an S3 bucket and its permissions. Using Amazon Athena to query the S3 bucket and to visualize the results in a pie chart format is also a valid way to analyze the data, but it incurs charges based on the amount of data scanned by each query. Exporting the results from Athena and attaching them to the desired CloudWatch dashboard is also an extra step that adds more overhead and latency.

Option C is incorrect because it uses AWS X-Ray for an inappropriate purpose. Updating the ecommerce application to use AWS X-Ray for instrumentation is a good practice for monitoring and tracing distributed applications, but it is not designed for aggregating product transaction details. Creating a new X-Ray subsegment and adding an annotation for each processed transaction is possible, but it would clutter the X-Ray service map and make it harder to debug performance issues. Using X-Ray traces to query the data and to visualize the results in a pie chart format is also possible, but it would require custom code and logic that are not supported by X-Ray natively. Attaching the results to the desired CloudWatch dashboard is also not supported by X-Ray directly, and would require additional steps or services.

Option D is incorrect because it introduces unnecessary complexity and cost. Updating the ecommerce application to emit a JSON object to a CloudWatch log group for each processed transaction is a simple and cost-effective way to collect the data needed for the dashboard, as in option A. However, creating an AWS Lambda function to aggregate and write the results to Amazon DynamoDB is redundant, as CloudWatch Logs Insights can already perform aggregation queries on log data. Creating a Lambda subscription filter for the log file is also redundant, as CloudWatch Logs Insights can already access log data directly. Attaching the results to the desired CloudWatch dashboard would also require additional steps or services, as DynamoDB does not support native integration with CloudWatch dashboards.

Container restart failures require detailed observability into pod-level, node-level, and container-level metrics and logs. CloudWatch Container Insights is purpose-built for Kubernetes operational diagnostics and provides granular visibility into CPU, memory, network I/O, disk I/O, container restarts, OOM kills, throttling, pod lifecycle issues, and Kubernetes control plane behaviors.

The CloudWatch Observability add-on deploys Fluent Bit and the CloudWatch Agent directly into the EKS cluster as DaemonSets. These components automatically collect:

Container logs

Pod metrics

Node metrics

Cluster events

OOM errors

CrashLoopBackOff restart cycles

Control plane request anomalies

With this data, the DevOps engineer can easily identify misconfigurations, resource bottlenecks, unhealthy nodes, failing containers, or image pull issues.

Option A (dashboards only) lacks per-container diagnostic data.

Option B (CloudTrail) only logs API calls — not useful for restart debugging.

Option C (CloudTrail Insights) only detects anomalous API usage, not container failures.

Therefore, CloudWatch Container Insights is the correct and AWS-recommended solution for diagnosing container restart failures in EKS.