ECS cluster concept in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

What is the primary role of an ECS cluster?

In Amazon ECS, what is the main purpose of an ECS cluster?

A It provides a user interface to configure container networking.

B It stores container images used by tasks and services.

C It monitors the health of individual containers inside tasks.

D It groups and manages a set of container instances or serverless tasks for running containers.

💡 Hint

Think about what a cluster usually means in computing: a group working together.

An ECS cluster is a logical grouping of container instances or serverless tasks that lets you manage and run your containers together.

❓ Architecture

intermediate

How does ECS cluster capacity affect task placement?

Which statement best describes how ECS cluster capacity influences where tasks are placed?

A Tasks are placed only on container instances with enough CPU and memory available in the cluster.

B Tasks are placed randomly across all container instances regardless of capacity.

C Tasks are placed only on the newest container instance added to the cluster.

D Tasks are placed on container instances outside the cluster if capacity is low.

💡 Hint

Consider resource availability when placing containers.

ECS schedules tasks on container instances that have enough CPU and memory resources available within the cluster.

❓ security

advanced

Which ECS cluster setting improves security by isolating workloads?

Which ECS cluster configuration helps improve security by isolating workloads?

A Running all tasks in a single cluster to simplify management.

B Using separate ECS clusters for different environments like development and production.

C Allowing all container instances to share the same IAM role without restrictions.

D Disabling task-level IAM roles to reduce complexity.

💡 Hint

Think about how separating environments can limit risks.

Using separate ECS clusters for different environments isolates workloads and limits the blast radius in case of security issues.

❓ service_behavior

advanced

What happens if an ECS cluster has no registered container instances?

What is the expected behavior when an ECS cluster has no registered container instances and you try to run a task using EC2 launch type?

A The task fails to start because there are no container instances to run it on.

B The task runs on any available container instance in other clusters.

C The task automatically runs on AWS Fargate instead.

D The task starts but remains in a stopped state immediately.

💡 Hint

Consider what is needed to run a task with EC2 launch type.

EC2 launch type tasks require registered container instances in the cluster to run. Without any, the task cannot start.

✅ Best Practice

expert

Which ECS cluster design best supports high availability and fault tolerance?

To ensure high availability and fault tolerance for your ECS workloads, which cluster design is best?

A Use a single large container instance instead of multiple smaller ones.

B Deploy all container instances in a single Availability Zone to reduce latency.

C Deploy container instances across multiple Availability Zones within the cluster.

D Run all tasks on AWS Fargate without any container instances.

💡 Hint

Think about spreading risk across locations.

Deploying container instances across multiple Availability Zones helps maintain service if one zone fails, improving availability and fault tolerance.