DOP-C02 Monitoring and Logging Practice Test 11 — 15 Questions

Question 1

A DevOps team wants to monitor the disk space utilization on their EC2 instances. What is the simplest way to achieve this?

Accepted Answer

Install the CloudWatch agent on the EC2 instances and configure the disk metric.. The CloudWatch agent can collect disk space metrics from EC2 instances, which is not available with default CloudWatch metrics. Option A is incorrect because AWS Systems Manager Inventory is used for software inventory and configuration, not real-time disk space monitoring. Option C is incorrect because EC2 detailed monitoring only provides more frequent metrics for standard EC2 metrics (CPU, network, etc.), not disk metrics. Option D is incorrect because EC2 basic monitoring also does not include disk metrics.

Answer

Use AWS Systems Manager Inventory to collect disk space data.

Answer

Enable EC2 detailed monitoring in CloudWatch.

Answer

Use EC2 basic monitoring in CloudWatch.

Question 2

A company runs a web application on Amazon EC2 instances behind an Application Load Balancer (ALB). The application logs show that some requests are timing out. The team needs to identify the source of the issue. Which TWO steps should they take?

Accepted Answer

Enable ALB access logs and analyze them.. A is correct because ALB access logs provide detailed information about each HTTP request, including the request method, URL, response status, and timing, which can help identify why requests are timing out. D is correct because CloudWatch metrics for the ALB, such as 'RequestCount' and 'TargetResponseTime', allow you to monitor the number of requests per target and the time it takes for targets to respond, helping pinpoint which targets are experiencing timeouts. B is wrong because VPC Flow Logs capture IP traffic metadata (source, destination, protocol) but do not provide application-level request details or timing information. C is wrong because AWS WAF logs only record details about requests that are allowed or blocked by web ACL rules, not general request processing. E is wrong because CloudTrail logs API calls made to AWS services, not the application requests arriving at the ALB.

Answer

Enable VPC Flow Logs to capture network traffic.

Answer

Enable AWS WAF logs to inspect HTTP requests.

Answer

Enable AWS CloudTrail to log all API calls.

Question 3

A DevOps engineer is designing a centralized logging solution for a multi-account AWS environment. The solution must be cost-effective and provide real-time log analysis. Which THREE services should they consider?

Accepted Answer

Amazon OpenSearch Service (Elasticsearch). Amazon OpenSearch Service (option A) provides real-time log analysis and visualization, making it a core component for centralized logging. Amazon Kinesis Data Firehose (option B) enables near-real-time streaming of log data to destinations like OpenSearch or S3, facilitating cost-effective ingestion. Amazon CloudWatch Logs (option D) can centralize logs from multiple AWS services and accounts, with subscription filters to stream to Kinesis Firehose or OpenSearch. Option C (Amazon S3) is a storage service, not suitable for real-time analysis itself, though it can serve as a destination. Option E (AWS CloudTrail) records API activity but is not a centralized logging service for all logs.

Answer

Amazon S3

Answer

AWS CloudTrail

Question 4

A company uses AWS Lambda for data processing. The operations team wants to be alerted when a function fails. Which TWO methods can they use?

Accepted Answer

Configure a dead-letter queue (DLQ) for the Lambda function and monitor the queue.. Options C and D are correct. Option C: Configuring a dead-letter queue (DLQ) for the Lambda function allows failed invocations to be sent to an SQS queue or SNS topic, which can then trigger alerts (e.g., via CloudWatch alarms on the queue). Option D: Creating a CloudWatch alarm on the 'Errors' metric for the Lambda function directly monitors the error count and can trigger an SNS notification. Option A is wrong because S3 event notifications are triggered by S3 events, not Lambda errors. Option B is wrong because CloudTrail logs API calls to Lambda (e.g., Invoke), not the execution errors of the function. Option E is wrong because AWS Config is for tracking configuration changes, not runtime errors.

Answer

Configure S3 event notifications to trigger on Lambda errors.

Answer

Enable AWS CloudTrail to log Lambda invocations.

Answer

Use AWS Config to detect Lambda function failures.

Question 5

A DevOps engineer runs the command above to retrieve CPU utilization for an EC2 instance, but gets no data points. The instance is running and has basic monitoring enabled. What is the most likely reason?

Accepted Answer

The IAM user executing the command lacks 'cloudwatch:GetMetricStatistics' permission.. The command likely fails because the IAM user executing it does not have the 'cloudwatch:GetMetricStatistics' permission. Basic monitoring publishes CPUUtilization metrics every 5 minutes (300 seconds), so a period of 300 seconds is valid. The dimension name 'InstanceId' is correct as shown. Option A is wrong because the dimension name is case-sensitive and 'InstanceId' is correct. Option B is wrong because basic monitoring is enabled by default and publishes CPUUtilization. Option C is wrong because 300 seconds equals the default 5-minute interval, which is the minimum supported period for basic monitoring.

Answer

The dimension name should be 'InstanceId' with a different case.

Answer

The instance has basic monitoring disabled.

Answer

The period of 300 seconds is less than the minimum supported period.

Question 6

A Lambda function is timing out. The log above shows a recent invocation. What is the most likely cause?

Accepted Answer

The function timeout is set too low.. The log shows the function timed out at 3000 ms, which is the default Lambda timeout (3 seconds). The correct answer is D because the timeout value is set too low, causing the function to be terminated before it can complete. Option A is incorrect because memory usage is only 64 MB out of 128 MB, so insufficient memory is not the issue. Option B is incorrect because there is only one invocation shown; frequent invocations would cause throttling, not a timeout. Option C is incorrect because the init duration is normal (e.g., 2.34 ms), indicating that a cold start is not the cause; cold starts increase latency but do not cause timeouts if the function runs within the timeout limit.

Answer

The function is running out of memory.

Answer

The function is being invoked too frequently.

Answer

The function is experiencing a cold start.

Question 7

A company is using an Application Load Balancer (ALB) in front of an Auto Scaling group of EC2 instances. The operations team notices that the error rate on the ALB is increasing, but the CPU utilization on the EC2 instances remains low. Which CloudWatch metric should be examined to determine if the errors are due to a lack of healthy targets?

Accepted Answer

HealthyHostCount. (HealthyHostCount) is correct because it indicates the number of healthy targets per Availability Zone. If this count drops, the ALB may not have enough healthy instances to serve requests, leading to errors such as 503s. Option A (UnHealthyHostCount) shows unhealthy hosts but does not directly correlate with the error rate caused by a lack of healthy targets. Option B (RequestCount) measures total requests, not health. Option D (TargetResponseTime) measures latency, not availability.

Answer

UnHealthyHostCount

Answer

RequestCount

Answer

TargetResponseTime

Question 8

A DevOps engineer is configuring CloudWatch Logs for a Lambda function that processes streaming data from Kinesis. The function sometimes fails due to memory exhaustion. The engineer wants to ensure that logs from the function are shipped to CloudWatch Logs even when the function fails. Which configuration should be used?

Accepted Answer

Ensure the Lambda function writes logs to stdout or stderr; CloudWatch Logs will automatically capture them. Lambda functions automatically send all output written to stdout (via print or console.log) and stderr to CloudWatch Logs, regardless of whether the function succeeds or fails. This is a built-in behavior of the Lambda runtime, so no additional agents or configuration are needed to capture logs from a failed invocation due to memory exhaustion.

Answer

Configure a Kinesis Agent on the Lambda execution environment to stream logs to CloudWatch Logs

Answer

Install the CloudWatch Logs agent on the Lambda function to continuously send logs

Answer

Enable detailed CloudWatch metrics for the Lambda function

Question 9

A company uses Amazon CloudWatch to monitor its production environment. The DevOps team wants to receive an email notification whenever the average CPU utilization of any EC2 instance exceeds 90% for 5 consecutive minutes. Which steps should be taken to set up this notification?

Accepted Answer

Create a CloudWatch alarm on CPUUtilization with a threshold of 90% for 5 consecutive periods, and configure an SNS topic to send email. Create a CloudWatch alarm on the CPUUtilization metric with a threshold of 90% for 5 consecutive periods (5 minutes assuming 1-minute periods), and configure an SNS topic to send email notifications. Option A is incorrect because the CloudWatch Logs agent collects log data, not metrics, and metric filters are for log analysis, not setting alarms on CPU utilization. Option C is incorrect because AWS CloudTrail logs API calls, not CPU utilization metrics. Option D is incorrect because AWS Config is for resource configuration auditing and compliance, not for monitoring CPU utilization metrics.

Answer

Install the CloudWatch Logs agent on each EC2 instance and configure a metric filter to trigger an SNS notification

Answer

Use AWS CloudTrail to monitor CPU utilization and send notifications via SNS

Answer

Use AWS Config to create a rule that triggers an SNS notification when CPU utilization exceeds 90%

Question 10

A company runs a critical application on an Auto Scaling group of EC2 instances behind an Application Load Balancer (ALB). The DevOps team needs to implement a dashboard that shows real-time request latency, error rates, and the number of healthy hosts. Which AWS service should be used to create this dashboard?

Accepted Answer

Amazon CloudWatch Dashboards. Amazon CloudWatch Dashboards is the correct choice because it provides real-time monitoring and visualization of metrics such as request latency, error rates, and healthy host counts directly from CloudWatch. These metrics are automatically emitted by the Application Load Balancer (e.g., TargetResponseTime, HTTPCode_ELB_5XX_Count, HealthyHostCount) and can be displayed on a customizable dashboard without additional data transformation or querying.

Answer

Amazon QuickSight

Answer

AWS CloudTrail

Answer

AWS Config

Question 11

A DevOps engineer is troubleshooting a slow web application. The application runs on EC2 instances behind an ALB. The engineer notices that the ALB's TargetResponseTime metric shows high p99 values, but the CPU and memory on the EC2 instances are well below thresholds. What is the most likely cause?

Accepted Answer

The application is waiting on a slow database query or external API call. High p99 TargetResponseTime on the ALB with low CPU and memory on the EC2 instances indicates that the bottleneck is not compute capacity but rather a dependency external to the application server. The application is likely waiting on a slow database query or external API call, which increases response time without consuming significant local CPU or memory. This is a classic symptom of an I/O-bound or network-bound dependency.

Answer

The Auto Scaling group has too many instances, causing increased network overhead

Answer

The ALB is routing requests to instances in different Availability Zones, increasing latency

Answer

The ALB idle timeout is set too low, causing connections to be dropped

Question 12

A company wants to monitor the number of messages that are published to an Amazon SNS topic. Which CloudWatch metric should be used?

Accepted Answer

NumberOfMessagesPublished. The CloudWatch metric 'NumberOfMessagesPublished' tracks the number of messages published to an SNS topic. Option A (SMSMonthToDateSpentUSD) tracks monthly SMS spend, not messages published. Option B (PublishSize) is not a standard SNS metric; the relevant metric is 'PublishSize' for message size, but it's not for counting messages. Option C (NumberOfNotificationsDelivered) counts messages delivered to subscribers, not published.

Answer

SMSMonthToDateSpentUSD

Answer

PublishSize

Answer

NumberOfNotificationsDelivered

Question 13

A DevOps engineer receives an alarm that an EC2 instance's StatusCheckFailed metric has been in ALARM state for 10 minutes. Which action should the engineer take first to investigate?

Accepted Answer

Review the instance's system log and application logs in CloudWatch Logs. When an EC2 instance's StatusCheckFailed metric is in ALARM state, it indicates a problem with the instance itself (OS-level or application-level). Reviewing the instance's system log and application logs in CloudWatch Logs is the first step to diagnose the root cause. Option B (AWS Config) checks configuration compliance, which is not directly related to the health check failure. Option C (CloudTrail) logs API calls but not OS-level issues. Option D (restart) may temporarily resolve the issue but does not provide investigation.

Answer

Use AWS Config to check the instance's configuration compliance

Answer

Check AWS CloudTrail for any API calls that modified the instance

Answer

Restart the EC2 instance to clear the alarm

Question 14

A company wants to receive a notification when an AWS IAM user creates a new access key. Which AWS service should be used to capture this event and trigger a notification?

Accepted Answer

AWS CloudTrail with CloudWatch Events. AWS CloudTrail captures API activity, including the CreateAccessKey event when an IAM user creates a new access key. By sending these events to Amazon CloudWatch Events (now part of Amazon EventBridge), you can define a rule that triggers a notification via SNS, Lambda, or other targets. This combination provides the real-time event-driven notification the company requires.

Answer

Amazon GuardDuty

Answer

Amazon CloudWatch

Answer

AWS Config

Question 15

A DevOps team is setting up centralized logging for a multi-account AWS environment. They want to aggregate logs from all accounts into a single S3 bucket. Which services should be used to achieve this? (Choose TWO.)

Accepted Answer

AWS CloudTrail. AWS CloudTrail is correct because it can be configured to deliver log files from multiple accounts to a single S3 bucket by setting up a trail in the management account and using the 'Enable for all accounts in my organization' option, which automatically applies the trail to all member accounts in AWS Organizations. This centralizes CloudTrail logs without requiring per-account configuration.

Answer

AWS Config

Answer

Amazon Kinesis Data Firehose

Answer

Amazon S3 replication