Contents:

Overview

In this section, we will deploy multiple container services (microservices) to an ECS Cluster using AWS Fargate.
Each service will handle a specific function such as an API service, a frontend service, or a background worker.

Advantages of a microservices approach:

  • Improved scalability for individual components
  • Easier maintenance and upgrades without affecting the entire system
  • Reduced risk if a single service fails

Create Task Definitions for each service

  1. Service 1 – API

    • Go to ECS Console → Task Definitions → Create new Task Definition
    • Select Fargate
    • Name: api-service-task
    • Select Task Role: ecsTaskExecutionRole
    • Add container:
      • Name: api-service
      • Image: <AWS_ACCOUNT_ID>.dkr.ecr.us-east-1.amazonaws.com/api-service:latest
      • Port mappings: 8080
    • Save and create the Task Definition.

  2. Service 2 – Frontend

    • Similar to Service 1, but:
      • Name: frontend-service
      • Image: <AWS_ACCOUNT_ID>.dkr.ecr.us-east-1.amazonaws.com/frontend-service:latest
      • Port mappings: 80

  3. Service 3 – Worker (Background Job)

    • Similar, but:
      • Name: worker-service
      • Image: <AWS_ACCOUNT_ID>.dkr.ecr.us-east-1.amazonaws.com/worker-service:latest
      • No port mapping required if not exposed externally

Deploy services to ECS Cluster

  1. Deploy API Service

    • Go to ECS Console → Select your Cluster → Create Service
    • Launch type: Fargate
    • Task Definition: api-service-task
    • Service name: api-service
    • Desired tasks: 2
    • Networking:
      • Select VPC and Subnets
      • Enable Assign Public IP if public access is needed
      • Choose Security Group that allows port 8080
    • (Optional) Attach to Application Load Balancer target group

  2. Deploy Frontend Service

    • Same as API Service, but:
      • Task Definition: frontend-service-task
      • Port: 80
      • Security Group allows port 80

  3. Deploy Worker Service

    • Similar, but:
      • Task Definition: worker-service-task
      • No ALB attachment
      • Runs in private subnet

Verify deployment

  • Go to ECS Console → Cluster → Services tab
  • Ensure service status is Running
  • If service is attached to an ALB:

    • Go to EC2 Console → Load Balancers

    • Copy the ALB DNS name

    • Test from browser or use:

      curl http://<ALB_DNS_NAME>/health

Expected result: You should receive a 200 OK response or a valid API message.