AWS Certified SysOps Administrator SOA-C01 – Question701

A company has created an online retail application that is hosted on a fleet of Amazon EC2 instances behind an ELB Application Load Balancer. User authentication is handled at the individual EC2 instance level. Once a user is authenticated; all requests from that user must go to the same EC2 instance. What should the SysOps Administrator enable to meet these requirements?

A. ELB TCP listeners
B. ELB sticky sessions
C. ELB connection draining
D. ELB cross-zone load balancing

Correct Answer: B

Explanation:

Explanation: ELB can be configured to use sticky session feature (also called session affinity) which enables it to bind a user’s session to an instance and ensures all requests are sent to the same instance. Stickiness remains for a period of time which can be controlled by the application’s session cookie, if one exists, or through cookie, named AWSELB, created through Elastic Load balancer. Sticky sessions for ELB are disabled, by default.