I'm currently using ECS Fargate with one task definition that runs two containers: a frontend that listens on port 2000 and a backend on port 3000. The frontend uses Nginx to proxy requests from the `/api` path to the backend container. I have an Application Load Balancer (ALB) that forwards traffic to the frontend on port 2000. I'm looking to separate this setup into two task definitions—one for each container. I want the ALB to continue sending regular traffic to the frontend but also route any traffic targeting the `/api` path to the backend container on port 3000. Can anyone guide me on how to achieve this?
3 Answers
If your frontend is a Node.js app and the backend is just an API, make sure your ALB is set up to handle path-based routing. You want it to forward any request that starts with `/api` directly to your backend container, while the rest goes to the frontend.
This isn't specific to Fargate, but for backend services, you might want to utilize internal endpoints, like AWS CloudMap. This can help with service discovery and routing without exposing everything publicly.
To split your containers into separate task definitions, you'll need to configure the ALB with listener rules that route traffic based on the request path. You can create two target groups: one for your frontend and another for your backend. The ALB can handle basic path routing, so unless you have specific needs that require Nginx, consider removing it altogether. If your frontend primarily serves static content, you could use an S3 bucket paired with CloudFront to simplify things further. That way, you can point your Route 53 domain directly at CloudFront, which could then target your ALB as well!
Yeah, Nginx is great for serving static files, but if it's just proxying API requests, the ALB can handle that pretty well!