AWS Certified Associate SAA-C03 Book

This answer is correct because it meets the requirements of optimizing cost and reducing the workload on the database. Amazon CloudFront is a content delivery network (CDN) service that speeds up distribution of your static and dynamic web content, such as .html, .css, .js, and image files, to your users. CloudFront delivers your content through a worldwide network of data centers called edge locations. When a user requests content that you’re serving with CloudFront, the request is routed to the edge location that provides the lowest latency (time delay), so that content is delivered with the best possible performance. You can create an Amazon CloudFront distribution to host the static web contents from an Amazon S3 bucket, which is an origin that you define for CloudFront. This way, you can offload the requests for static web content from your EC2 instances to CloudFront, which can improve the performance and availability of your website, and reduce the cost of running your EC2 instances.

References:

• https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/Introduction.html
• https://docs.aws.amazon.com/AmazonS3/latest/userguide/WebsiteHosting.html

Spot Instances are EC2 instances that are available at up to a 90% discount compared to On-Demand prices. Spot Instances are suitable for stateless, fault-tolerant, and flexible workloads that can tolerate interruptions. Spot Instances can be reclaimed by EC2 when the demand for On-Demand capacity increases, but they provide a two-minute warning before termination. EKS managed node groups automate the provisioning and lifecycle management of nodes for EKS clusters. Managed node groups can use Spot Instances to reduce costs and scale the cluster based on demand. Managed node groups also support features such as Capacity Rebalancing and Capacity Optimized allocation strategy to improve the availability and resilience of Spot Instances. This solution will meet the requirements most cost-effectively, as it leverages the lowest-priced EC2 capacity and does not require any manual intervention.

References:

• 1 explains how to create and use managed node groups with EKS.
• 2 describes how to use Spot Instances with managed node groups.
• 3 provides an overview of Spot Instances and their benefits.

it allows CloudFormation to access the template in the S3 bucket without granting public access or creating additional resources. A presigned URL is a URL that is signed with the access key of an IAM user or role that has permission to access the object. The presigned URL can be used by anyone who receives it, but it expires after a specified time. By creating a presigned URL for the template object and configuring the CloudFormation stack to use it, the company can grant CloudFormation access to the template based on specific user requests and follow security best practices. References:

• Using Amazon S3 Presigned URLs
• Using Amazon S3 Buckets

To migrate the DNS hosting service to a more resilient managed DNS service on AWS, the company should use Amazon Route 53, which is a highly available and scalable cloud DNS web service. Route 53 can host public DNS records for the company’s domain name and provide reliable and secure DNS resolution. To rapidly migrate the DNS hosting service, the company should create a public hosted zone for the domain name in Route 53, which is a container for the domain’s DNS records. Then, the company should import the zone file containing the domain records hosted by the previous provider, which is a text file that defines the DNS records for the domain. This way, the company can quickly transfer the existing DNS records to Route 53 without manually creating them. After importing the zone file, the company should update the domain registrar to use the name servers that Route 53 assigns to the hosted zone. This will ensure that DNS queries for the domain name are routed to Route 53 and resolved by the imported records.