Introduction
Deploying microservices at scale often requires a platform that handles container orchestration, networking, monitoring, and autoscaling. AWS offers several options, but ECS with Fargate is one of the simplest and most powerful ways to run Spring Boot microservices in production. It removes the need to manage servers, clusters, or EC2 instances. In this post, you’ll learn how ECS works, how Fargate simplifies deployment, and how to get your Spring Boot microservices running smoothly in the cloud.
What Are ECS and Fargate?
AWS ECS (Elastic Container Service) is Amazon’s fully managed container orchestrator. It handles tasks such as running containers, balancing traffic, and scaling your services.
AWS Fargate is the serverless compute engine for ECS. It lets you run containers without managing EC2 machines. Because of this, Fargate becomes an ideal choice for microservices where you want full automation and minimal operational overhead.
Key Benefits
- No servers or clusters to manage
- Automatic scaling and health checks
- Integration with IAM, CloudWatch, ALB, Secrets Manager
- Predictable pricing based on CPU and memory
- Works seamlessly with Docker-based Spring Boot apps
As a result, ECS + Fargate offer a clean and reliable deployment path for containerized Spring Boot applications.
Preparing Your Spring Boot Microservice
Start by containerizing your application.
Example Dockerfile
FROM eclipse-temurin:17-jdk-alpine
COPY target/app.jar app.jar
ENTRYPOINT ["java", "-jar", "app.jar"]
Build and push the image:
docker build -t your-repo/app .
aws ecr create-repository --repository-name your-repo/app
docker tag your-repo/app:latest <AWS_ACCOUNT>.dkr.ecr.<REGION>.amazonaws.com/your-repo/app:latest
docker push <AWS_ACCOUNT>.dkr.ecr.<REGION>.amazonaws.com/your-repo/app:latest
Your microservice is now ready to run on ECS.
Creating an ECS Cluster
Although Fargate doesn’t require EC2 machines, ECS still organizes workloads into logical clusters.
Create a Cluster
- Go to ECS Console → Create Cluster
- Select Networking Only (Fargate)
- Name your cluster and finish
Your cluster is now serverless and ready for tasks.
Defining a Task for Spring Boot
Tasks define how your containers run.
Example Task Definition
Set the following:
- Launch Type: Fargate
- CPU & Memory: e.g., 512 CPU, 1GB RAM
- Container Image: ECR image URL
- Port Mappings: 8080 → 8080
- Environment Vars: DB config, API keys
- Logging: CloudWatch Logs integration
Since Spring Boot listens on port 8080 by default, Fargate exposes that port automatically.
Running the Microservice as a Service
Next, create an ECS service to keep your microservice running.
Steps
- Select your cluster
- Click Create Service
- Choose Fargate
- Pick your task definition
- Configure:
- Desired task count
- Load balancer (if needed)
- Auto scaling
Because ECS services restart your tasks automatically, you don’t need to manage uptime yourself.
Integrating with an Application Load Balancer
Most microservices run behind a load balancer for routing and health checking.
ALB Setup
- Create an HTTP listener (80) or HTTPS listener (443)
- Add a target group for your service
- Set health check path (for Spring Boot:
/actuator/health) - Attach it to the ECS service
With this setup, your microservice receives traffic reliably and scales automatically based on load.
Handling Secrets and Configuration
Avoid storing sensitive credentials inside your containers. Instead, use:
- AWS Secrets Manager for database passwords
- AWS SSM Parameter Store for config values
- IAM Roles for Tasks for secure access to AWS resources
This makes your microservices safer and easier to maintain.
Autoscaling Your Microservices
Fargate supports automatic scaling based on CPU, memory, or custom CloudWatch metrics.
Example Scaling Rule
- Scale out when CPU > 70%
- Scale in when CPU < 30%
This helps your services adjust to traffic spikes while reducing costs during low-load periods.
Logging and Monitoring
AWS provides out-of-the-box tools for observability:
- CloudWatch Logs: Application logs
- CloudWatch Metrics: CPU, memory, and network
- ECS Console: Service health and task events
You can also integrate Prometheus exporters and Grafana for deeper insight.
When to Use ECS + Fargate
Choose ECS + Fargate when you want:
- Fully managed container execution
- Strict cost control
- Minimal operations work
- Simple deployment model
- Smooth Spring Boot integration
If you need more customization or advanced mesh networking, EKS (Kubernetes) is another option.
Final Thoughts
Deploying Spring Boot microservices to AWS ECS and Fargate provides a clean, scalable, and hands-off way to run your applications in the cloud. You package your service as a Docker image, upload it to ECR, define a task, and let AWS handle the rest. It’s a great match for teams that want the power of containers without managing cluster infrastructure. To continue building your cloud skills, read Serverless Applications with AWS Lambda & API Gateway. For detailed deployment instructions, explore the Amazon ECS documentation.