Amazon Web Services Updated DOP-C02 Exam Questions and Answers by miriam

Comprehensive and Detailed Explanation From Exact Extract:

The Amazon SQS service publishes several standard CloudWatch metrics by default, including ApproximateNumberOfMessagesVisible, which represents the number of messages available for retrieval from the queue (i.e., the number of messages waiting to be processed). This is the primary metric to monitor queue backlog and processing delays.

Using ApproximateNumberOfMessagesVisible to monitor the visible messages in the queue gives a direct and near real-time indication of processing delays or backlog.

CloudWatch metrics are automatically collected and available without the need to create custom metrics or Lambda functions, which increases operational efficiency by reducing complexity and maintenance overhead.

Setting a CloudWatch alarm on this metric with a static threshold and a reasonable evaluation period (such as 1 hour) is sufficient to alert the team when the queue grows beyond an expected size.

The alarm can be directly configured to send notifications to an existing SNS topic, maintaining seamless integration with the team’s alerting mechanisms.

The ApproximateNumberOfMessagesDelayed metric refers to messages that are delayed and not available for processing yet due to delay settings, which is not the direct backlog that causes business process delays.

Options C and D introduce unnecessary complexity by requiring Lambda functions and custom metrics or scheduled invocations, which reduce operational efficiency compared to using built-in CloudWatch metrics and alarms.

Reference from AWS Official Documentation and Study Guide:

Amazon SQS Monitoring with CloudWatch Metrics:"Amazon SQS automatically sends metrics to CloudWatch, including ApproximateNumberOfMessagesVisible, which shows the number of messages available for retrieval."(Source: Amazon SQS Monitoring - AWS Documentation)

Setting CloudWatch Alarms for SQS Queues:"You can create CloudWatch alarms on SQS metrics such as ApproximateNumberOfMessagesVisible to receive notifications when the queue size exceeds a threshold."(Source: Amazon CloudWatch Alarms - AWS Documentation)

AWS DevOps Engineer Professional Exam Guide:"Efficient alerting for queue backlogs should leverage native CloudWatch metrics to minimize operational overhead."(Source: Official AWS Certified DevOps Engineer Professional Study Guide)

A comprehensive and detailed explanation is:

Option A is incorrect because EventBridge rules cannot filter events based on the message body or attributes of the target service. Therefore, configuring an SNS subscription filter policy to match the CloudFormation stack will not work. The SNS topic will receive all events from the EventBridge rule, regardless of the stack name or drift status.

Option B is incorrect because it introduces unnecessary complexity and cost. Creating a second Lambda function to query the CloudFormation API for the drift detection results is redundant, since CloudFormation already publishes drift detection events to EventBridge. Moreover, invoking two Lambda functions every hour will incur more charges than invoking one.

Option C is incorrect because GuardDuty does not provide drift detection for CloudFormation stacks. GuardDuty is a threat detection service that monitors for malicious activity and unauthorized behavior in AWS accounts and workloads. It does not monitor or report on configuration changes or drifts in CloudFormation stacks.

Option D is correct because it leverages AWS Config and its managed rule for drift detection. AWS Config is a service that enables you to assess, audit, and evaluate the configurations of your AWS resources. It can detect configuration changes and drifts in CloudFormation stacks using the cloudformation-stack-drift-detection-check managed rule. This rule triggers an AWS Config event when a stack drifts from its expected template configuration. By creating a second EventBridge rule that reacts to this event for the specific stack, the DevOps engineer can configure the SNS topic as a target and receive a notification as soon as possible when drift is detected.

Step 1: Reducing Replication Lag in Aurora Global DatabasesIn Amazon Aurora global databases, write operations on the primary cluster can be delayed due to the time it takes to replicate to secondary clusters, especially when there are multiple secondary regions involved.

Issue: The write operations are occasionally blocked due to the RPO setting, which guarantees replication within 60 seconds.

Action: Remove one of the secondary clusters from the global database.

Why: Fewer secondary clusters will reduce the overall replication lag, improving write performance and reducing the frequency of blocked writes.

https://aws.amazon.com/quickstart/architecture/blue-green-deployment/