20+ practice questions focused on Incident and Event Response — one of the most tested topics on the AWS Certified DevOps Engineer Professional DOP-C02 exam. Each question includes a detailed explanation so you learn why the right answer is correct.
Start Incident and Event Response PracticeA company uses an Auto Scaling group with a dynamic scaling policy based on a custom CloudWatch metric. After a recent deployment, the metric spikes unexpectedly, causing the Auto Scaling group to launch several EC2 instances. The operations team wants to quickly determine whether the spike was caused by a real load increase or a deployment issue. What is the MOST efficient way to investigate this?
Explanation: Option B is correct because CloudWatch Logs Insights allows you to query application logs for error patterns or deployment markers (e.g., new version tags, exception stack traces) that coincide with the metric spike. This directly correlates the scaling event with application-level evidence, enabling rapid root-cause analysis without altering infrastructure or relying on indirect notifications.
A company runs a critical application on Amazon ECS with Fargate launch type. The application uses an Application Load Balancer (ALB) in front. During a load test, the team notices a sudden increase in 5xx errors from the ALB, and some tasks become unhealthy. The task logs show occasional 'OutOfMemoryError' exceptions. The task definition currently has 512 CPU units and 1024 MiB memory. What should the team do to mitigate the issue while maintaining a cost-effective approach?
Explanation: Option B is correct because the application is experiencing OutOfMemoryError, indicating the current 1024 MiB memory allocation is insufficient. Increasing memory to 2048 MiB while keeping CPU at 512 units directly resolves the memory constraint without unnecessary CPU cost. ECS Fargate allows independent scaling of CPU and memory within valid combinations, and this change maintains a cost-effective approach by only increasing the resource that is actually constrained.
A DevOps engineer is investigating an incident where an EC2 instance became unreachable. The engineer checks the AWS Management Console and finds the instance is running, but the status check shows '2/2 checks passed' and the system log shows no errors. What should the engineer do NEXT to diagnose the connectivity issue?
Explanation: Since the instance is running, status checks pass, and the system log shows no errors, the issue is not with the operating system or underlying hardware. The most likely cause is a network-layer restriction, such as security group or network ACL rules blocking inbound traffic. Checking these rules is the correct next step because they control traffic at the instance and subnet levels, respectively, and misconfigurations here are a common cause of unreachability despite healthy instance status.
A company has an AWS Lambda function that processes S3 events. The function is invoked multiple times for the same S3 object, causing duplicate processing. The engineer suspects the issue is related to retries from the S3 event notification or Lambda's built-in retry behavior. What is the MOST effective way to ensure idempotent processing?
Explanation: Option B is correct because storing processed S3 object keys in a DynamoDB table and checking for existence before processing ensures idempotency at the application level. This approach directly handles duplicate invocations caused by S3 event retries or Lambda's built-in retry behavior, as the function can conditionally skip processing if the key already exists in DynamoDB. It provides a durable, consistent, and scalable mechanism to prevent duplicate processing regardless of how many times the function is invoked for the same object.
An organization uses AWS CloudFormation to manage infrastructure. During an incident, a stack update fails with 'UPDATE_ROLLBACK_FAILED' status. The engineer needs to bring the stack to a consistent state without losing data. What is the BEST approach?
Explanation: The 'ContinueUpdateRollback' API is the best approach because it allows the stack to resume the rollback process, skipping the resource that caused the failure, and bringing the stack to a consistent 'UPDATE_ROLLBACK_COMPLETE' state without manual intervention or data loss. This API is specifically designed for the 'UPDATE_ROLLBACK_FAILED' status, enabling you to skip resources that cannot be rolled back (e.g., due to a non-reversible change) while preserving the rest of the stack's state.
+15 more Incident and Event Response questions available
Practice all Incident and Event Response questions1. Baseline your knowledge
Start with 10 questions to gauge your current understanding of Incident and Event Response. This tells you whether you need a concept refresher or just practice.
2. Review every explanation
For each question — right or wrong — read the full explanation. Understanding why an answer is correct is more valuable than knowing the answer itself.
3. Focus on exam traps
Incident and Event Response questions on the DOP-C02 frequently use trap wording. Look for subtle differences in answers that test your precision, not just general knowledge.
4. Reach 80% consistently
Do repeated sessions until you score 80%+ three times in a row. Then move to mixed-mode practice to test cross-topic recall under realistic conditions.
The exact number varies per candidate. Incident and Event Response is tested as part of the AWS Certified DevOps Engineer Professional DOP-C02 blueprint. Practicing with targeted Incident and Event Response questions ensures you can handle any format or difficulty that appears.
Yes. Courseiva provides free DOP-C02 practice questions across all exam topics and domains. The platform includes topic-based practice, mock exams, missed-question review, bookmarked questions, and readiness tracking — no account required.
Difficulty is subjective, but Incident and Event Response is a high-priority exam concept tested in multiple ways — direct recall, scenario analysis, and command-output interpretation. Consistent practice is the best way to build confidence.
Launch a full Incident and Event Response practice session with instant scoring and detailed explanations.
Start Incident and Event Response Practice →