Amazon Elastic Container Service (ECS) provides a comprehensive solution for managing and orchestrating Docker containers on AWS, offering flexibility and performance for modern applications.
Amazon ECS (Elastic Container Service) is a highly scalable, high-performance container orchestration service. It can run containers on EC2 instances or using AWS Fargate (serverless compute).
ECS/EKS are ideal for microservices. Containers allow code reuse, independent team ownership, and easy scaling.
ECS offers flexible deployment models for running containers, catering to different operational and infrastructure management preferences.
EC2 Launch Type
With the EC2 launch type, containers run on Amazon EC2 instances. This option provides granular control over the underlying infrastructure.
AWS Fargate Launch Type
AWS Fargate provides serverless compute for containers, abstracting away the underlying infrastructure management. This allows users to focus solely on their applications.
Use Cases:
- Running containerized applications while avoiding operational overhead.
ECS Anywhere
ECS Anywhere connects on-premise ECS-managed containers, offering an external launch type that standardizes container management across diverse environments outside the AWS cloud.
ECS provides built-in features to manage, scale, and secure containerized applications, enhancing operational efficiency and reliability.
ECS offers orchestration for launching and managing Docker containers on AWS compute resources.
ECS services include Auto Scaling capabilities to automatically handle scaling requirements based on demand, ensuring applications maintain performance during fluctuating loads.
A Task Role is assigned to tasks within containers, allowing the applications running inside those containers to perform AWS actions securely.
The Task Execution Role grants permissions to the ECS agent and services, enabling them to perform actions such as pulling Docker images from Amazon ECR.
Sensitive information can be passed to ECS tasks securely by referencing it via 'valueFrom' to AWS Secrets Manager or AWS Systems Manager Parameter Store.
Amazon ECS integrates with a variety of other AWS services to provide a comprehensive and robust environment for containerized applications.
ECS integrates with both Network Load Balancers (NLBs) and Application Load Balancers (ALBs) to distribute incoming application traffic across containerized services. For example, ECS can be the target for an Application Load Balancer.
A new feature in Amazon Inspector maps ECR container images with running containers across Amazon ECS or EKS, aiding in vulnerability management.
Amazon EFS supports multiple compute instances, including EC2, ECS, and Lambda, running in different Availability Zones within the same VPC, providing shared file storage for containers.
DataSync can be used for transferring data between storage services, such as from Amazon S3 to EFS, which can then be used by applications running on ECS/Fargate.
App2Container (A2C) is a CLI tool designed for lifting and shifting existing applications into containers. ECS is one of the supported services for deploying these containerized applications.
Amazon ECS is suitable for a variety of workloads, particularly those requiring high scalability, efficiency, and simplified management of containerized applications.
ECS is a correct solution for migrating on-premises monolithic applications to AWS, breaking them into smaller, manageable microservices. This preserves existing code, enables independent team ownership, and supports easy scaling, all while minimizing operational overhead when used with an Application Load Balancer (ALB).
ECS on AWS Fargate is an ideal choice for running containerized applications when the primary goal is to minimize operational overhead by not managing the underlying server infrastructure.
A container-based architecture using ECS Fargate, Amazon RDS PostgreSQL, and an Application Load Balancer (ALB) follows a traditional cloud-native philosophy with containers and a managed database, offering a familiar environment for teams experienced with Docker and SQL databases.
This section outlines a specific container-based architecture example using Amazon ECS Fargate, Amazon RDS for PostgreSQL, and an Application Load Balancer (ALB), detailing its components, costs, and suitability for various use cases.
Philosophy
This architecture adheres to a traditional cloud-native approach, leveraging containers for application deployment and a managed database service.
AWS Services Used (Example Configuration)
Configuration detail for AWS Services Used (Example Configuration).
compute:
Amazon ECS Fargate (2 tasks × 0.25 vCPU, 0.5 GB)
load_balancing:
Application Load Balancer
database:
Amazon RDS PostgreSQL (db.t4g.micro)
storage:
Amazon S3 for static assets
networking:
VPC with private subnets, NAT Gateway
authentication:
Flask-Login + RDS or AWS Cognito
ci_cd:
GitHub Actions → ECR → CodeDeploy
Estimated Cost (50 users)
The estimated monthly cost for this architecture, serving 50 users, with options for optimization.
total_cost_range:
$40-90/month
fargate_cost:
$17.77
alb_cost:
$16.78
rds_cost:
$15.72
nat_gateway_cost:
$32.85 (biggest cost)
optimized_cost_with_vpc_endpoints:
$40-50/month
Pros
Key advantages of adopting this ECS Fargate-based architecture for containerized applications.
Use Cases:
- Familiar architecture (Flask → PostgreSQL)
- Predictable costs
- SQL database flexibility (JOINs, ad-hoc queries)
- Minimal code changes
- Docker portability
Cons
Potential drawbacks and complexities associated with this architecture, particularly for small-scale deployments.
Use Cases:
- Higher baseline cost ($40-90/month)
- NAT Gateway cost trap ($33/month)
- More moving parts (VPC, subnets, security groups)
- Over-provisioned for small scale
When to Choose
This architecture is recommended under specific conditions and team capabilities.
Use Cases:
- Team knows Docker and PostgreSQL
- Budget allows $40-90/month
- Plan to scale to 1,000+ users soon
- Need long-running requests (>30 seconds)
- Want database query flexibility