- (Exam Topic 3)
A company runs an application on a large fleet of Amazon EC2 instances. The application reads and write entries into an Amazon DynamoDB table. The size of the DynamoDB table continuously grows, but the application needs only data from the last 30 days. The company needs a solution that minimizes cost and development effort.
Which solution meets these requirements?

1. A. Use an AWS CloudFormation template to deploy the complete solutio
2. B. Redeploy the CloudFormation stack every 30 days, and delete the original stack.
3. C. Use an EC2 instance that runs a monitoring application from AWS Marketplac
4. D. Configure the monitoring application to use Amazon DynamoDB Streams to store the timestamp when a new item is created in the tabl
5. E. Use a script that runs on the EC2 instance to delete items that have a timestamp that is older than 30 days.
6. F. Configure Amazon DynamoDB Streams to invoke an AWS Lambda function when a new item is created in the tabl
7. G. Configure the Lambda function to delete items in the table that are older than 30 days.
8. H. Extend the application to add an attribute that has a value of the current timestamp plus 30 days to each new item that is created in the tabl
9. I. Configure DynamoDB to use the attribute as the TTL attribute.

Correct Answer: D
Amazon DynamoDB Time to Live (TTL) allows you to define a per-item timestamp to determine when an item is no longer needed. Shortly after the date and time of the specified timestamp, DynamoDB deletes the item from your table without consuming any write throughput. TTL is provided at no extra cost as a means to reduce stored data volumes by retaining only the items that remain current for your workload’s needs.
TTL is useful if you store items that lose relevance after a specific time. The following are example TTL use cases:
Remove user or sensor data after one year of inactivity in an application.
Archive expired items to an Amazon S3 data lake via Amazon DynamoDB Streams and AWS Lambda. Retain sensitive data for a certain amount of time according to contractual or regulatory obligations. https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/TTL.html

- (Exam Topic 1)
A company is storing sensitive user information in an Amazon S3 bucket The company wants to provide secure access to this bucket from the application tier running on Ama2on EC2 instances inside a VPC.
Which combination of steps should a solutions architect take to accomplish this? (Select TWO.)

1. A. Configure a VPC gateway endpoint for Amazon S3 within the VPC
2. B. Create a bucket policy to make the objects to the S3 bucket public
3. C. Create a bucket policy that limits access to only the application tier running in the VPC
4. D. Create an IAM user with an S3 access policy and copy the IAM credentials to the EC2 instance
5. E. Create a NAT instance and have the EC2 instances use the NAT instance to access the S3 bucket

Correct Answer: AC
https://aws.amazon.com/premiumsupport/knowledge-center/s3-private-connection-no-authentication/

- (Exam Topic 1)
A company is running a popular social media website. The website gives users the ability to upload images to share with other users. The company wants to make sure that the images do not contain inappropriate content. The company needs a solution that minimizes development effort.
What should a solutions architect do to meet these requirements?

1. A. Use Amazon Comprehend to detect inappropriate conten
2. B. Use human review for low-confidence predictions.
3. C. Use Amazon Rekognition to detect inappropriate conten
4. D. Use human review for low-confidence predictions.
5. E. Use Amazon SageMaker to detect inappropriate conten
6. F. Use ground truth to label low-confidence predictions.
7. G. Use AWS Fargate to deploy a custom machine learning model to detect inappropriate conten
8. H. Use ground truth to label low-confidence predictions.

Correct Answer: B
https://docs.aws.amazon.com/rekognition/latest/dg/moderation.html?pg=ln&sec=ft https://docs.aws.amazon.com/rekognition/latest/dg/a2i-rekognition.html

- (Exam Topic 3)
A company recently deployed a new auditing system to centralize information about operating system versions patching and installed software for Amazon EC2 instances. A solutions architect must ensure all instances provisioned through EC2 Auto Scaling groups successfully send reports to the auditing system as soon as they are launched and terminated
Which solution achieves these goals MOST efficiently?

1. A. Use a scheduled AWS Lambda function and run a script remotely on all EC2 instances to send data to the audit system.
2. B. Use EC2 Auto Scaling lifecycle hooks to run a custom script to send data to the audit system when instances are launched and terminated
3. C. Use an EC2 Auto Scaling launch configuration to run a custom script through user data to send data to the audit system when instances are launched and terminated
4. D. Run a custom script on the instance operating system to send data to the audit system Configure the script to be invoked by the EC2 Auto Scaling group when the instance starts and is terminated

Correct Answer: B

- (Exam Topic 1)
A company wants to reduce the cost of its existing three-tier web architecture. The web, application, and database servers are running on Amazon EC2 instances for the development, test, and production environments. The EC2 instances average 30% CPU utilization during peak hours and 10% CPU utilization during non-peak hours.
The production EC2 instances run 24 hours a day. The development and test EC2 instances run for at least 8 hours each day. The company plans to implement automation to stop the development and test EC2 instances when they are not in use.
Which EC2 instance purchasing solution will meet the company's requirements MOST cost-effectively?

1. A. Use Spot Instances for the production EC2 instance
2. B. Use Reserved Instances for the development and test EC2 instances.
3. C. Use Reserved Instances for the production EC2 instance
4. D. Use On-Demand Instances for the development and test EC2 instances.
5. E. Use Spot blocks for the production EC2 instance
6. F. Use Reserved Instances for the development and test EC2 instances.
7. G. Use On-Demand Instances for the production EC2 instance
8. H. Use Spot blocks for the development and test EC2 instances.

Correct Answer: B