A developer is deploying a multi-container Docker application on Amazon ECS using the Fargate launch type. The application consists of a web server and a background worker. The web server must be scaled independently and must be accessible from the internet via an Application Load Balancer. The worker should not be accessible from the internet. Which ECS configuration should the developer use?

Create one ECS service with both containers in the same task definition, but only expose the web server port.

Both containers would be in the same task and would scale together. The worker would also be in the public subnet, potentially exposing it, and independent scaling is not possible.

Create one ECS service with two tasks, each containing one container.

This is essentially two tasks in one service, which would still share the same service scaling settings and placement. It does not allow independent scaling or subnet placement per container.

Create one ECS service with two containers in the same task, and use a service discovery to expose the worker.

Service discovery is for internal DNS, not for scaling or network access. The worker would be in the same task and subnet as the web server, likely exposing it.

What does this DVA-C02 question test?

CIDR notation defines the prefix length.

What is the correct answer to this question?

The correct answer is: Create two separate ECS services, each with its own task definition, and place the web server in a public subnet with the worker in a private subnet. — To scale independently and control internet access, the best practice is to create separate ECS services with their own task definitions. The web server service should be placed in a public subnet with an ALB, while the worker service should be placed in a private subnet without public access. This provides independent scaling and security.

What should I do if I get this DVA-C02 question wrong?

Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.