Architecting on AWS Certification AWS Certified Solutions Architect - Associate 3 — Questions and Answers
Question 1: A company runs a stateful web application behind an Application Load Balancer. Users are being logged out unexpectedly when requests hit different EC2 instances. What is the simplest fix?
- Switch to a Network Load Balancer
- Enable sticky sessions on the ALB target group (Correct answer)
- Deploy an ElastiCache cluster for session storage
- Migrate to AWS Lambda
Correct answer: Enable sticky sessions on the ALB target group
Enabling sticky sessions (session affinity) on the ALB target group ensures a user's requests always go to the same instance during their session.
Question 2: Which S3 storage class is most cost-effective for data that is accessed less than once a month and requires rapid retrieval when needed?
- S3 Standard
- S3 Standard-IA
- S3 Glacier Instant Retrieval (Correct answer)
- S3 Glacier Deep Archive
Correct answer: S3 Glacier Instant Retrieval
S3 Glacier Instant Retrieval offers the lowest storage cost for rarely accessed data while still providing millisecond retrieval times.
Question 3: A Solutions Architect needs to allow an EC2 instance to call AWS APIs without embedding credentials in the application. What is the best practice?
- Store credentials in an environment variable
- Use an IAM role attached to the EC2 instance (Correct answer)
- Use the root account access key
- Store credentials in AWS Secrets Manager and rotate daily
Correct answer: Use an IAM role attached to the EC2 instance
Attaching an IAM role to an EC2 instance provides temporary credentials automatically via the instance metadata service with no credential management needed.
Question 4: An application needs to send notifications to both an SQS queue and an email subscriber whenever a new order is placed. Which AWS service enables fan-out to multiple endpoints simultaneously?
- Amazon SQS FIFO
- Amazon EventBridge Scheduler
- Amazon SNS (Correct answer)
- AWS Step Functions
Correct answer: Amazon SNS
SNS supports a publish/subscribe model that fans out a single message to multiple subscribers including SQS queues and email endpoints.
Question 5: A company's RDS MySQL database is experiencing read bottlenecks. The application performs far more reads than writes. What is the most appropriate solution?
- Enable Multi-AZ deployment
- Create one or more RDS Read Replicas (Correct answer)
- Increase the RDS instance size
- Enable automated backups
Correct answer: Create one or more RDS Read Replicas
RDS Read Replicas offload read traffic from the primary instance using asynchronous replication, reducing read bottlenecks.
Question 6: Which AWS service provides a fully managed FIFO message queue that guarantees exactly-once processing and preserves message order?
- Amazon SNS
- Amazon SQS Standard
- Amazon SQS FIFO (Correct answer)
- Amazon Kinesis Data Streams
Correct answer: Amazon SQS FIFO
SQS FIFO queues guarantee that messages are delivered in the exact order they are sent and are processed exactly once.
Question 7: A developer needs to quickly provision a WordPress site on AWS without managing servers. Which combination of services provides the best managed solution?
- EC2 + EBS + manually installed WordPress
- AWS Elastic Beanstalk with a PHP environment
- Amazon Lightsail with a WordPress blueprint (Correct answer)
- AWS Lambda + API Gateway
Correct answer: Amazon Lightsail with a WordPress blueprint
Amazon Lightsail provides pre-configured WordPress blueprints with managed servers, storage, and networking at a predictable low cost.
Architecting on AWS Certification AWS Certified Solutions Architect - Associate 3
A company runs a stateful web application behind an Application Load Balancer.
Users are being logged out unexpectedly when requests hit different EC2 instances.
What is the simplest fix?