- (Topic 4)
A company is designing a new web application that will run on Amazon EC2 Instances. The application will use Amazon DynamoDB for backend data storage. The application traffic will be unpredictable. T company expects that the application read and write throughput to the database will be moderate to high. The company needs to scale in response to application traffic.
Which DynamoDB table configuration will meet these requirements MOST cost-effectively?
Correct Answer:
B
The most cost-effective DynamoDB table configuration for the web application is to configure DynamoDB in on-demand mode by using the DynamoDB Standard table class. This configuration will allow the company to scale in response to application traffic and pay only for the read and write requests that the application performs on the table.
On-demand mode is a flexible billing option that can handle thousands of requests per second without capacity planning. On-demand mode automatically adjusts the table’s capacity based on the incoming traffic, and charges only for the read and write requests that are actually performed. On-demand mode is suitable for applications with unpredictable or variable workloads, or applications that prefer the ease of paying for only what they use1.
The DynamoDB Standard table class is the default and recommended table class for most workloads. The DynamoDB Standard table class offers lower throughput costs than the DynamoDB Standard-Infrequent Access (DynamoDB Standard-IA) table class, and is more cost-effective for tables where throughput is the dominant cost. The DynamoDB Standard table class also offers the same performance, durability, and availability as the DynamoDB Standard-IA table class2.
The other options are not correct because they are either not cost-effective or not suitable for the use case. Configuring DynamoDB with provisioned read and write by using the DynamoDB Standard table class, and setting DynamoDB auto scaling to a maximum defined capacity is not correct because this configuration requires manual estimation and management of the table’s capacity, which adds complexity and cost to the solution. Provisioned mode is a billing option that requires users to specify the amount of read and write capacity units for their tables, and charges for the reserved capacity regardless of usage. Provisioned mode is suitable for applications with predictable or stable workloads, or applications that require finer-grained control over their capacity settings1. Configuring DynamoDB with provisioned read and write by using the DynamoDB Standard-Infrequent Access (DynamoDB Standard-IA) table class, and setting DynamoDB auto scaling to a maximum defined capacity is not correct because this configuration is not cost-effective for tables with moderate to high throughput. The DynamoDB Standard-IA table class offers lower storage costs than the DynamoDB Standard table class, but higher throughput costs. The DynamoDB Standard-IA table class is optimized for tables where storage is the dominant cost, such as tables that store infrequently accessed data2. Configuring DynamoDB in on-demand mode by using the DynamoDB Standard-Infrequent Access (DynamoDB Standard-IA) table class is not correct because this configuration is not cost- effective for tables with moderate to high throughput. As mentioned above, the DynamoDB Standard-IA table class has higher throughput costs than the DynamoDB Standard table class, which can offset the savings from lower storage costs.
References:
✑ Table classes - Amazon DynamoDB
✑ Read/write capacity mode - Amazon DynamoDB
- (Topic 1)
A company wants to run its critical applications in containers to meet requirements tor scalability and availability The company prefers to focus on maintenance of the critical applications The company does not want to be responsible for provisioning and managing the underlying infrastructure that runs the containerized workload
What should a solutions architect do to meet those requirements?
Correct Answer:
C
using AWS ECS on AWS Fargate since they requirements are for scalability and availability without having to provision and manage the underlying infrastructure to run the containerized workload. https://docs.aws.amazon.com/AmazonECS/latest/userguide/what-is-fargate.html
- (Topic 4)
A company is subscribed to the AWS Business Support plan. Compliance rules require the company to check on AWS infrastructure health before deployments can proceed. The company needs a programmatic and automated way to check on infrastructure health at the beginning of new deployments.
Which solution will meet these requirements?
Correct Answer:
B
The AWS Health API provides programmatic access to the AWS Health information that is presented in the AWS Personal Health Dashboard. You can use the API operations to get information about AWS Health events that affect your AWS services and resources. You can also use the API to enable or disable health-based insights for your organization. You can use the AWS Health API at the start of each deployment to check on AWS infrastructure health and pause all new deployments if the API returns any issues. References: https://docs.aws.amazon.com/health/latest/APIReference/Welcome.html
- (Topic 4)
A company wants to deploy its containerized application workloads to a VPC across three Availability Zones. The company needs a solution that is highly available across Availability Zones. The solution must require minimal changes to the application.
Which solution will meet these requirements with the LEAST operational overhead?
Correct Answer:
A
The company wants to deploy its containerized application workloads to a VPC across three Availability Zones, with high availability and minimal changes to the application. The solution that will meet these requirements with the least operational overhead is:
✑ Use Amazon Elastic Container Service (Amazon ECS). Amazon ECS is a fully
managed container orchestration service that allows you to run and scale containerized applications on AWS. Amazon ECS eliminates the need for you to install, operate, and scale your own cluster management infrastructure. Amazon ECS also integrates with other AWS services, such as VPC, ELB, CloudFormation, CloudWatch, IAM, and more.
✑ Configure Amazon ECS Service Auto Scaling to use target tracking scaling.
Amazon ECS Service Auto Scaling allows you to automatically adjust the number of tasks in your service based on the demand or custom metrics. Target tracking scaling is a policy type that adjusts the number of tasks in your service to keep a specified metric at a target value. For example, you can use target tracking scaling to maintain a target CPU utilization or request count per task for your service.
✑ Set the minimum capacity to 3. This ensures that your service always has at least
three tasks running across three Availability Zones, providing high availability and fault tolerance for your application.
✑ Set the task placement strategy type to spread with an Availability Zone attribute.
This ensures that your tasks are evenly distributed across the Availability Zones in your cluster, maximizing the availability of your service.
This solution will provide high availability across Availability Zones, require minimal changes to the application, and reduce the operational overhead of managing your own cluster infrastructure.
References:
✑ Amazon Elastic Container Service
✑ Amazon ECS Service Auto Scaling
✑ Target Tracking Scaling Policies for Amazon ECS Services
✑ Amazon ECS Task Placement Strategies
- (Topic 3)
A gaming company is moving its public scoreboard from a data center to the AWS Cloud. The company uses Amazon EC2 Windows Server instances behind an Application Load Balancer to host its dynamic application. The company needs a highly available storage solution for the application. The application consists of static files and dynamic server-side code.
Which combination of steps should a solutions architect take to meet these requirements? (Select TWO.)
Correct Answer:
AD
A because Elasticache, despite being ideal for leaderboards per Amazon, doesn't cache at edge locations. D because FSx has higher performance for low latency needs. https://www.techtarget.com/searchaws/tip/Amazon-FSx-vs-EFS-Compare-the-AWS-file- services "FSx is built for high performance and submillisecond latency using solid-state drive storage volumes. This design enables users to select storage capacity and latency independently. Thus, even a subterabyte file system can have 256 Mbps or higher throughput and support volumes up to 64 TB."
Amazon S3 is an object storage service that can store static files such as images, videos, documents, etc. Amazon EFS is a file storage service that can store files in a hierarchical structure and supports NFS protocol. Amazon FSx for Windows File Server is a file storage service that can store files in a hierarchical structure and supports SMB protocol. Amazon EBS is a block storage service that can store data in fixed-size blocks and attach to EC2 instances.
Based on these definitions, the combination of steps that should be taken to meet the requirements are:
* A. Store the static files on Amazon S3. Use Amazon CloudFront to cache objects at the edge. D. Store the server-side code on Amazon FSx for Windows File Server. Mount the FSx for Windows File Server volume on each EC2 instance to share the files.
