Deployment Types in Amazon ECS (Elastic Container Service)
Source: Dev.to
Introduction
Amazon Elastic Container Service (Amazon ECS) is a fully managed container orchestration solution that simplifies the deployment, management, and scaling of containerized applications on AWS. A key factor in operating applications on ECS is the method used to deploy new versions of your application. This article explores the deployment types in Amazon ECS, explains how each works, identifies when to use them, and discusses best practices. It is especially useful for DevOps and cloud engineers.
What Are ECS Deployment Types?
Deployment types in ECS define how new versions of a task definition are introduced to your active services. ECS supports several strategies depending on your launch type and load‑balancing configuration:
- ECS with EC2 launch type
- ECS with AWS Fargate
- ECS with an Application Load Balancer (ALB)
The primary ECS deployment types are:
- Rolling Deployment (ECS default)
- Blue/Green Deployment (using AWS CodeDeploy)
- External Deployment (custom / third‑party)
Rolling Deployment (ECS Default Deployment)
Rolling deployment is the standard method in Amazon ECS. ECS gradually replaces old tasks with new ones based on the updated task definition.
How It Works
- ECS starts new tasks using the revised task definition.
- Existing tasks are phased out gradually.
- The process is governed by deployment configuration settings (e.g., minimum healthy percent, maximum percent).
Blue/Green Deployment (Using AWS CodeDeploy)
- Blue – current production version
- Green – new version to be released
Traffic is shifted from the blue environment to the green environment in a controlled manner.
How It Works
- Traffic routing strategies can be:
- Simultaneous (all at once)
- Straight (linear)
- Canary (incremental)
- Once the green tasks are verified, the old (blue) tasks are terminated.
Requirements
- Application Load Balancer (ALB)
- ECS service configured with the CodeDeploy deployment controller
- Two target groups (Blue & Green) attached to the ALB
External Deployment (Custom Deployment)
External deployments rely on an outside system to manage task and service updates.
How It Works
- An external tool or script updates the ECS service and tasks.
- You control scaling, traffic shifting, and rollback procedures.
Common Tools Used
- Jenkins
- GitHub Actions
- Argo CD
- Custom scripts using the AWS SDK or AWS CLI
Conclusion
Amazon ECS offers a range of deployment options to match different application needs. Rolling deployments are simple and cost‑effective, Blue/Green deployments provide enterprise‑grade reliability with zero downtime, and External deployments give you full control for complex scenarios. Understanding these deployment types helps you build robust, scalable, and dependable containerized applications on AWS ECS.
References
- https://docs.aws.amazon.com/AmazonECS/latest/developerguide/Welcome.html
- https://docs.aws.amazon.com/AmazonECS/latest/developerguide/deployment-type-bluegreen.html
- https://docs.aws.amazon.com/codedeploy/latest/userguide/deployment-steps-ecs.html
- https://docs.aws.amazon.com/codedeploy/latest/userguide/welcome.html
- https://docs.aws.amazon.com/AmazonECS/latest/developerguide/deployment-type-external.html
- https://docs.aws.amazon.com/AmazonECS/latest/developerguide/service-load-balancing.html
- https://docs.aws.amazon.com/elasticloadbalancing/latest/application/target-group-health-checks.html