AWS Certified Developer – Associate — Question 385

A company is running an application on Amazon Elastic Container Service (Amazon ECS). When the company deploys a new version of the application, the company initially needs to expose 10% of live traffic to the new version. After a period of time, the company needs to immediately route all the remaining live traffic to the new version.
Which ECS deployment should the company use to meet these requirements?

Answer options

• A. Rolling update
• B. Blue/green with canary
• C. Blue/green with all at once
• D. Blue/green with linear

Correct answer: B

Explanation

A blue/green with canary deployment configuration allows routing a specific percentage of traffic (e.g., 10%) to the new Amazon ECS task set for a set interval before shifting the remaining traffic (90%) all at once. In contrast, linear deployments shift traffic in equal increments over time, all-at-once deployments shift 100% of traffic immediately, and rolling updates gradually replace tasks without this specific traffic-splitting control.