AWS Certified Advanced Networking Specialty Practice Exam

What does the lack of sticky sessions in the ELB configuration indicate?

1. All requests will be handled consistently by the same server

2. User sessions will not persist between requests

3. Sessions will scale across multiple regions

4. All traffic will follow a single path

The correct answer is: User sessions will not persist between requests

The correct answer identifies that the lack of sticky sessions in an Elastic Load Balancer (ELB) configuration indicates user sessions will not persist between requests. When sticky sessions are enabled, the load balancer routes all requests from a specific user to the same backend instance based on a session cookie. If sticky sessions are not configured, the load balancer treats every request independently, which means each request can go to different instances in the backend. As a result, there is no continuity in user sessions, potentially leading to a situation where a user might have to log in again if their requests are handled by different servers that do not share session state. This setup is particularly useful in stateless applications where individual requests do not rely on previous interactions, allowing for better load distribution and scaling. However, if an application does require session persistence, not having sticky sessions would disrupt the user experience as session data would not be retained between requests.