AWS - Certified Solutions Architect High Availability and Scalability Questions and Answers

Question 1

A company is designing a critical application on AWS that requires high availability and must withstand the failure of an entire Availability Zone.
The application consists of a fleet of EC2 instances and an Amazon RDS for PostgreSQL database.
Which combination of services provides the highest availability for this architecture?

Accepted Answer

An Application Load Balancer across multiple Availability Zones, an EC2 Auto Scaling group across multiple Availability Zones, and an RDS Multi-AZ deployment.

Answer

An Application Load Balancer across multiple Availability Zones, an EC2 Auto Scaling group across multiple Availability Zones, and a single RDS instance.

Answer

An Application Load Balancer in a single Availability Zone, an EC2 Auto Scaling group in a single Availability Zone, and an RDS Multi-AZ deployment.

Answer

An Application Load Balancer across multiple Availability Zones, an EC2 Auto Scaling group in a single Availability Zone, and an RDS instance with Read Replicas.

Question 2

A solutions architect is designing a read-heavy application that uses an Amazon RDS database. The primary goal is to improve read performance and offload queries from the primary database instance. Which RDS feature is the most appropriate solution to meet this requirement?

Accepted Answer

Read Replicas

Answer

Multi-AZ Deployments

Answer

Automated Backups

Answer

Database Snapshots

Question 3

An application running on EC2 instances behind an Application Load Balancer experiences unpredictable traffic spikes. The company wants to ensure that the application can handle the increased load automatically without manual intervention and also scale down to reduce costs during quiet periods. Which AWS service should be used in conjunction with the Application Load Balancer?

Accepted Answer

Amazon EC2 Auto Scaling

Answer

AWS Lambda

Answer

Amazon CloudWatch Alarms

Answer

Elastic IP Addresses

Question 4

A global application requires the lowest possible latency for both dynamic and static content delivered to users worldwide. The application uses non-HTTP protocols (TCP/UDP) for some of its real-time components and needs a static IP address to be whitelisted by clients. Which service is the best choice to meet these requirements?

Accepted Answer

AWS Global Accelerator

Answer

Amazon CloudFront with a custom origin

Answer

Elastic Load Balancer with cross-zone load balancing

Answer

Amazon Route 53 with latency-based routing

Question 5

Which of the following describes the primary difference between vertical and horizontal scaling?

Accepted Answer

Vertical scaling increases the capacity of a single resource (e.g., CPU, RAM), while horizontal scaling adds more resources (e.g., instances) to a pool.

Answer

Vertical scaling adds more instances to a resource pool, while horizontal scaling increases the size of a single instance.

Answer

Vertical scaling is only applicable to databases, while horizontal scaling is only for web servers.

Answer

Vertical scaling provides high availability, while horizontal scaling provides fault tolerance.

Question 6

A company needs to store critical, frequently accessed data in Amazon S3 with the highest level of availability and durability. The data must be resilient to the failure of an entire AWS Availability Zone. Which S3 storage class should be used?

Accepted Answer

S3 Standard

Answer

S3 One Zone-Infrequent Access (S3 One Zone-IA)

Answer

S3 Glacier Deep Archive

Answer

S3 Intelligent-Tiering