AWS Certified Solutions Architect Associate SAA-C03 Practice Question

Designing microservices to be stateless means they do not store any session information or client-specific data locally. By storing user session data in an external data store e.g., AWS DynamoDB or RDS, you decouple service instances from the user state, allowing any instance to handle any request. This approach facilitates horizontal scaling and improves fault tolerance, as instances can be added or removed without affecting user sessions. Conversely, maintaining session state in memory or local binds the user session to a specific instance, making the service stateful and hindering scalability. Managing user sessions with stateful connections also introduces statefulness, defeating the goal of a stateless architecture.