DOP-C02 Monitoring and Logging Practice Test 10 — 15 Questions

Question 1

A company runs a microservices architecture on Amazon EKS. The DevOps team wants to monitor application performance and detect anomalies in request latency. They need to collect metrics, logs, and traces from all services. Which THREE AWS services should the team use together to implement a complete observability solution? (Choose three.)

Accepted Answer

AWS X-Ray. Options A, B, and D are correct. CloudWatch Container Insights provides metrics and logs for EKS (Option A). AWS X-Ray provides distributed tracing (Option B). CloudWatch ServiceLens integrates CloudWatch metrics/logs and X-Ray traces into a single view (Option D). Option C (Prometheus) is not a native AWS service; Amazon Managed Service for Prometheus would be the AWS service, but the question asks for AWS services. Option E (CloudTrail) is for API activity, not application performance.

Answer

AWS CloudTrail

Answer

Amazon Managed Service for Prometheus

Question 2

A company is using Amazon CloudWatch to monitor its production environment. The operations team receives alerts for the same underlying issue from multiple alarms, causing alert fatigue. The team wants to reduce noise and consolidate alerts into actionable notifications. Which TWO steps should the team take? (Choose two.)

Accepted Answer

Configure the CloudWatch alarms to publish to an SNS topic, and use SNS subscription filter policies to route only critical notifications.. Options A and D are correct. CloudWatch Alarm composite alarms can combine multiple alarms into a single alarm with OR/AND logic (Option A). CloudWatch can publish to an SNS topic, and you can filter messages to reduce noise (Option D). Option B (CloudWatch Logs Insights) is for querying logs, not for alert consolidation. Option C (CloudWatch Evidently) is for feature flags. Option E (Config rules) is for compliance, not alerting.

Answer

Use CloudWatch Evidently to run experiments and filter out false alarms.

Answer

Use CloudWatch Logs Insights to query logs and create alarms based on the query results.

Answer

Use AWS Config rules to automatically suppress alarms that are not compliant.

Question 3

A company is using a centralized logging solution with Amazon OpenSearch Service. The DevOps team notices that logs from some EC2 instances are missing. The CloudWatch agent is installed and configured on all instances. What should the team do to troubleshoot the issue?

Accepted Answer

Check the CloudWatch agent log file located at /var/log/amazon/amazon-cloudwatch-agent/amazon-cloudwatch-agent.log.. The CloudWatch agent writes detailed operational logs to /var/log/amazon/amazon-cloudwatch-agent/amazon-cloudwatch-agent.log. This file contains errors, warnings, and debug messages that can reveal why logs from specific EC2 instances are not being delivered to Amazon OpenSearch Service. Checking this log is the first and most direct troubleshooting step because it captures agent-level issues such as configuration errors, network connectivity failures, or permission problems.

Answer

Check the CloudWatch agent status using the CloudWatch agent status command.

Answer

Configure a Lambda function to poll the CloudWatch agent for logs.

Answer

Verify that the EC2 instances have an SQS queue configured for log delivery.

Question 4

A company is running a critical application on Amazon ECS with Fargate. The application generates custom metrics that are published to CloudWatch using the PutMetricData API. Recently, the metrics have been delayed by up to 5 minutes. The DevOps team needs to reduce the latency. What should the team do?

Accepted Answer

Set the StorageResolution parameter to 1 when calling PutMetricData.. Option D is correct because the storage resolution parameter allows metrics to be stored at a higher resolution (1 second) which can be retrieved faster. Option A is wrong because the CloudWatch agent is not needed for custom API calls. Option B is wrong because increasing the PutMetricData frequency may cause throttling. Option C is wrong because CloudWatch Logs does not replace custom metrics.

Answer

Install the CloudWatch agent on the Fargate tasks to collect metrics.

Answer

Publish the metrics as structured logs to CloudWatch Logs and use metric filters.

Answer

Increase the frequency of PutMetricData calls to every 5 seconds.

Question 5

A DevOps engineer needs to set up an alert for when the CPU utilization of an EC2 instance exceeds 90% for 5 consecutive minutes. Which CloudWatch features should be used?

Accepted Answer

CloudWatch alarm on the CPUUtilization metric with a period of 5 minutes and threshold of 90.. Option B is correct because a CloudWatch alarm can monitor a metric and trigger an action when a threshold is breached for a specified period. Option A is wrong because CloudWatch Logs does not directly monitor CPU utilization. Option C is wrong because CloudTrail records API calls, not metrics. Option D is wrong because S3 does not provide monitoring or alerting.

Answer

CloudWatch Logs with a metric filter on CPU utilization logs.

Answer

CloudTrail to monitor EC2 instance CPU usage.

Answer

Amazon S3 server access logs to check CPU utilization.

Question 6

A company is using AWS X-Ray to trace requests through a microservices application. Some traces are incomplete, showing only the root segment without any subsegments. The application uses the X-Ray SDK for Java. What is the most likely cause?

Accepted Answer

The sampling rate is set to a low value, causing many requests to be dropped.. Option A is correct because if the sampling rate is too low, many requests are not traced, resulting in incomplete traces. Option B is wrong because segment size limits do not cause missing subsegments. Option C is wrong because a missing annotation would not prevent subsegments from appearing. Option D is wrong because the SDK automatically sends traces to the X-Ray daemon.

Answer

The application is missing the x-amzn-trace-id header in incoming requests.

Answer

The segment document size exceeds the maximum allowed size.

Answer

The X-Ray daemon is not running on the EC2 instances.

Question 7

A DevOps team needs to monitor failed API calls in their AWS account. They want to receive notifications when specific IAM actions, such as DeleteBucket, fail. Which service should they use?

Accepted Answer

AWS CloudTrail and Amazon EventBridge.. Option D is correct because CloudTrail logs API calls, and CloudWatch Events (now Amazon EventBridge) can be used to create rules that match specific API calls and trigger notifications. Option A is wrong because CloudWatch does not directly capture API calls. Option B is wrong because Config monitors resource configuration, not API calls. Option C is wrong because S3 access logs are for object-level operations.

Answer

AWS Config rules.

Answer

Amazon S3 server access logs.

Answer

CloudWatch Logs and metric filters.

Question 8

A company wants to visualize the performance of their application running on EC2. They need to create a dashboard that shows CPU utilization, memory usage, and disk I/O. Which AWS service should they use?

Accepted Answer

Amazon CloudWatch Dashboards.. Option A is correct because CloudWatch Dashboards can display metrics from EC2 and the CloudWatch agent, including memory and disk metrics. Option B is wrong because QuickSight is for business intelligence, not infrastructure monitoring. Option C is wrong because Systems Manager is for management, not visualization. Option D is wrong because CloudTrail is for auditing API calls.

Answer

AWS CloudTrail.

Answer

AWS Systems Manager.

Answer

Amazon QuickSight.

Question 9

A company is using Amazon RDS for MySQL and needs to monitor the number of slow queries. They have enabled slow query logs. How can they effectively monitor and alert on the number of slow queries per minute?

Accepted Answer

Publish slow query logs to CloudWatch Logs, create a metric filter, and set an alarm.. Option C is correct because you can publish slow query logs to CloudWatch Logs, create a metric filter to count occurrences, and set an alarm on that metric. Option A is wrong because RDS Events do not include slow query counts. Option B is wrong because Enhanced Monitoring does not include slow query logs. Option D is wrong because CloudTrail does not capture database queries.

Answer

Use RDS Events to send slow query metrics to CloudWatch.

Answer

Enable RDS Enhanced Monitoring and publish metrics to CloudWatch.

Answer

Use AWS CloudTrail to monitor SQL queries.

Question 10

A DevOps engineer is setting up centralized logging for multiple AWS accounts. They need to collect VPC Flow Logs, CloudTrail logs, and application logs into a single Amazon S3 bucket. What is the most efficient approach?

Accepted Answer

Use an S3 bucket in a centralized logging account with a bucket policy that grants write access from all other accounts.. Option B is correct because using an S3 bucket policy in a centralized account to allow cross-account log delivery is a common pattern. Option A is wrong because aggregating logs in a single account's S3 bucket requires cross-account permissions. Option C is wrong because Kinesis Data Firehose is not needed for simple log aggregation. Option D is wrong because Lambda functions would add complexity and cost.

Answer

Configure a Lambda function in each account to copy logs to a central S3 bucket.

Answer

Create an S3 bucket in each account and use S3 replication.

Answer

Use Amazon Kinesis Data Firehose to stream logs from all accounts to a central S3 bucket.

Question 11

A company wants to receive real-time notifications when their Auto Scaling group launches or terminates EC2 instances. Which AWS service should they use?

Accepted Answer

Amazon SNS notifications from the Auto Scaling group.. Option B is correct because Auto Scaling groups can send lifecycle notifications to Amazon SNS, which can then send emails or invoke Lambda. Option A is wrong because CloudWatch alarms are for metric thresholds, not lifecycle events. Option C is wrong because Config evaluates resource configurations. Option D is wrong because CloudTrail records API calls, but not real-time notifications.

Answer

Amazon CloudWatch alarm on the GroupTotalInstances metric.

Answer

AWS Config rules to detect changes in Auto Scaling groups.

Answer

AWS CloudTrail to monitor Auto Scaling API calls.

Question 12

A company is using Amazon CloudWatch Logs to store application logs. The DevOps team needs to search and analyze logs from multiple EC2 instances in real time. Which TWO services can be used to achieve this? (Choose TWO.)

Accepted Answer

Amazon OpenSearch Service.. Option A is correct because CloudWatch Logs Insights allows real-time querying of log groups. Option C is correct because CloudWatch Logs can stream to Amazon OpenSearch Service for real-time search and analytics. Option B is wrong because Athena is for ad-hoc querying of S3 data, not real-time. Option D is wrong because Kinesis Data Analytics is for streaming data analysis, not directly for log search. Option E is wrong because QuickSight is for visualization, not real-time search.

Answer

Amazon Athena.

Answer

Amazon QuickSight.

Answer

Amazon Kinesis Data Analytics.

Question 13

A company runs a containerized application on Amazon ECS with Fargate. They want to monitor the application logs and metrics. Which THREE steps should they take to collect and visualize this data? (Choose THREE.)

Accepted Answer

Create a CloudWatch Dashboard to display logs and metrics.. Option A is correct because the awslogs driver sends container logs to CloudWatch Logs. Option B is correct because enabling the CloudWatch agent in task definition allows custom metric collection. Option C is correct because CloudWatch Dashboards can visualize logs and metrics. Option D is wrong because X-Ray is for tracing, not logs or metrics. Option E is wrong because CloudFormation is for infrastructure provisioning, not monitoring.

Answer

Use AWS CloudFormation to monitor resource metrics.

Answer

Use AWS X-Ray to trace requests and collect logs.

Question 14

A DevOps engineer needs to monitor the health of a web application running on EC2 instances behind an Application Load Balancer (ALB). Which TWO metrics from ALB should be monitored to detect application errors? (Choose TWO.)

Accepted Answer

HTTPCode_Target_5XX_Count.. Option A is correct because HTTPCode_Target_5XX_Count indicates server errors. Option B is correct because TargetResponseTime can indicate performance issues leading to errors. Option C is wrong because RequestCount is total requests, not errors. Option D is wrong because HealthyHostCount is about host health, not application errors. Option E is wrong because HTTPCode_ELB_5XX_Count is for ALB itself, not targets.

Answer

RequestCount.

Answer

HTTPCode_ELB_5XX_Count.

Answer

HealthyHostCount.

Question 15

A company is running a web application on Amazon EC2 instances behind an Application Load Balancer. The application is experiencing intermittent errors. The DevOps engineer needs to identify if the errors are caused by the application or the underlying infrastructure. Which solution provides the MOST detailed visibility into the application's behavior?

Accepted Answer

Instrument the application with AWS X-Ray SDK and analyze traces. Option C is correct because AWS X-Ray provides end-to-end tracing of requests as they travel through the application, allowing the engineer to pinpoint where errors occur. Option A is wrong because CloudWatch metrics only show aggregate data, not per-request details. Option B is wrong because VPC Flow Logs capture network traffic metadata, not application-level errors. Option D is wrong because CloudTrail records API calls, not application errors.

Answer

Enable VPC Flow Logs and analyze traffic patterns

Answer

Enable AWS CloudTrail and monitor for API errors

Answer

Enable detailed CloudWatch metrics on the EC2 instances and ALB