Overview

Amazon ECS helps you run containerized applications (applications packaged in Docker containers) in the cloud. If you're familiar with EC2 instances, you can think of containers as lighter, faster-starting "mini virtual machines" that are perfect for running individual applications or services.

ECS takes care of the complex task of placing your containers across a cluster of servers (either EC2 instances you manage or using AWS Fargate where AWS manages everything). It ensures your applications are running reliably, can scale up or down based on demand, and automatically recovers if something goes wrong.

You can use ECS in two main ways: with EC2 instances (where you manage the servers your containers run on) or with AWS Fargate (where AWS manages all the infrastructure for you). Fargate is like having a serverless container platform - you just specify what you want to run, and AWS handles the rest.

ECS is particularly useful for modern application architectures, like microservices, where different parts of your application run in separate containers. It handles important tasks like load balancing, container scheduling, and maintaining high availability of your applications.

Example uses

Web Applications: Running web applications in containers, making them easy to update and scale. For example, running a Node.js web server and its database, each in separate containers.
Microservices: Breaking down a large application into smaller, independent services that can be developed, deployed, and scaled separately. Each microservice runs in its own container.
Batch Processing: Running periodic tasks or batch jobs in containers. For example, processing uploaded files or generating reports on a schedule.
API Services: Hosting APIs that other applications can communicate with, making it easy to scale the API service based on demand.

Integration with other AWS services

ECS works seamlessly with many popular AWS services:

Elastic Load Balancing: Automatically distributes incoming traffic across your containers using Application Load Balancers or Network Load Balancers.
Amazon ECR: Stores your Docker container images securely, making them easy to deploy to ECS.
AWS IAM: Controls who can access and manage your ECS resources and applications.
Amazon CloudWatch: Monitors your containers and collects logs, helping you track performance and troubleshoot issues.
AWS Auto Scaling: Automatically adjusts the number of containers running based on demand, similar to EC2 Auto Scaling groups.

Amazon Elastic Container Service (ECS)