- (Exam Topic 1)
A company maintains an application responsible for processing several thousand external callbacks each day. The company’s System administrators want to know how many callbacks are being received on a rolling basis, and they want this data available for 10 days. The company also wants the ability to issue automated alerts if the number of callbacks exceeds the defined thresholds.
What is the MOST cost-effective way to address the need to track and alert on these statistics?

1. A. Push callback data to an Amazon RDS database that can be queried to show historical data and to alert on exceeded thresholds.
2. B. Push callback data to AWS X-Ray and use AWS Lambda to query, display, and alert on exceeded thresholds.
3. C. Push callback data to Amazon Kinesis Data Streams and invoke an AWS Lambda function that stores data in Amazon DynamoDB and sends the required alerts.
4. D. Push callback data to Amazon CloudWatch as a custom metric and use the CloudWatch alerting mechanisms to alert System Administrators.

Correct Answer: D

- (Exam Topic 2)
A company runs continuous integration/continuous delivery (CI/CD) pipeline for its application on AWS CodePipeline. A developer must write unit tests and run them as part of the pipelines before staging the artifacts for testing.
How should the Developer incorporate unit tests as part of CI/CD pipeline?

1. A. Create a separate codePipline pipline to run unit tests.
2. B. Update the AWS codeBuild build specification to include a phase for running unit tests.
3. C. Install the AWS CodeDeploy agent on an Amazon EC2 instance to run unit tests.
4. D. Create a testing branch in AWS CodeCommit to run unit tests.

Correct Answer: B

- (Exam Topic 3)
A three-tier application hosted on AWS uses Amazon RDS for MYSQL as its database. A developer must ensure the database credentials are stored and accessed securely.
What is the MOST secure way for the developer to achieve this?

1. A. Store the credentials in a configuration file and commit it to the GIT repository.
2. B. Store the credentials in AWS Secrets Manager and enable automatic secret rotation.
3. C. Store the credentials using Amazon RDS and enable automatic rotation
4. D. Store the credentials in code and handle credentials rotation within the application.

Correct Answer: A

- (Exam Topic 2)
A social media company is using Amazon Cognito in order to synchronize profiles across different mobile devices, to enable end users to have a seamless experience.
Which of the following configurations can be used to silently notify users whenever an update is available on all other devices?

1. A. Modify the user pool to include all the devices which keep them in sync.
2. B. Use the SyncCallback interface to receive notifications on the application.
3. C. Use an Amazon Cognito stream to analyze the data and push the notifications.
4. D. Use the push synchronization feature with the appropriate IAM role.

Correct Answer: D
https://docs.aws.amazon.com/cognito/latest/developerguide/push-sync.html

- (Exam Topic 2)
A Developer is investigating an issue whereby certain requests are passing through an Amazon API Gateway endpoint /MyAPI, but the requests do not reach the AWS Lambda function backing /MyAPI. The Developer found that a second Lambda function sometimes runs at maximum concurrency allowed for the given AWS account.
How can the Developer address this issue?

1. A. Manually reduce the concurrent execution limit at the account level
2. B. Add another API Gateway stage for /MyAPI, and shard the requests
3. C. Configure the second Lambda function’s concurrency execution limit
4. D. Reduce the throttling limits in the API Gateway /MyAPI endpoint

Correct Answer: C
https://aws.amazon.com/about-aws/whats-new/2017/11/set-concurrency-limits-on-individual-aws-lambda-functi You can now set a concurrency limit on individual AWS Lambda functions. The concurrency limit you set will reserve a portion of your account level concurrency limit for a given function. This feature allows you to throttle a given function if it reaches a maximum number of concurrent executions allowed, which you can choose to set.