Question

A retail company is launching a new customer-facing web application built on a stateless containerized frontend running on Amazon ECS with AWS Fargate behind an Application Load Balancer. The engineering team must deploy frequent releases with zero downtime and the ability to instantly roll back to the previous version if error rates spike after a release. They want an AWS-managed deployment mechanism that shifts traffic between the old and new task sets and automatically triggers a rollback based on CloudWatch alarms. Which deployment strategy best meets these requirements?

Accepted Answer

Use AWS CodeDeploy with a blue/green deployment for the ECS service, shifting traffic via the ALB listener and configuring CloudWatch alarm-based automatic rollback.

Answer

Configure the ECS service to use a rolling update deployment with a minimum healthy percent of 100 and maximum percent of 200, relying on health checks to remove bad tasks.

Answer

Deploy new task definitions using an AWS CloudFormation stack update with UpdateReplacePolicy set to Retain to preserve the old version for rollback.

Answer

Use an Amazon Route 53 weighted routing policy to gradually shift DNS traffic from the old ALB to a new ALB fronting the updated task set.