AWS ECS Interview Questions:
1. AWS ECS Fundamentals
- Can you explain the architecture of AWS ECS?
- What are the main components of ECS, such as Task Definitions, Services, Clusters, and Tasks?
- What is the difference between ECS and EKS (Elastic Kubernetes Service)?
- How does ECS differ from Docker Swarm or Kubernetes?
- What are the differences between the Fargate and EC2 launch types in ECS?
2. Task Definitions and Services
- What is a Task Definition in ECS, and what role does it play?
- How do you configure and manage environment variables in ECS Task Definitions?
- Can you explain the difference between a Task and a Service in ECS?
- How do you handle updating or rolling back Task Definitions in ECS?
- What is the purpose of the Service Scheduler in ECS, and how does it manage tasks?
3. ECS Clusters
- How do you create and manage ECS Clusters?
- What are the key differences between using a dedicated EC2 instance cluster versus Fargate?
- How do you manage resource allocation and scaling within an ECS Cluster?
- What are ECS Container Instances, and how do they relate to Clusters?
- How do you handle cluster scaling and resource optimization in ECS?
4. Networking in ECS
- How do you configure networking for ECS tasks?
- What is the role of an ECS Service with an Application Load Balancer (ALB)?
- Can you explain how to set up and manage VPC networking for ECS tasks?
- How do you handle service discovery and DNS resolution in ECS?
- What is the difference between awsvpc, bridge, and host networking modes in ECS?
5. ECS Security
- How do you secure ECS tasks and services?
- What are the best practices for managing IAM roles and policies with ECS?
- How do you handle secrets management in ECS?
- Can you explain the concept of ECS Task Role and how it differs from an EC2 Instance Role?
- How do you ensure network security within an ECS environment, such as managing security groups and network ACLs?
6. ECS Scaling
- How do you implement auto-scaling for ECS services?
- What are the key metrics you monitor to scale ECS tasks and services?
- How do you configure ECS Service Auto Scaling based on custom CloudWatch metrics?
- What strategies do you use to handle scaling for applications with unpredictable traffic patterns?
- Can you explain how Cluster Auto Scaling works with ECS on EC2?
7. ECS and CI/CD
- How do you integrate ECS with CI/CD pipelines?
- What tools and practices do you use for deploying applications to ECS through CI/CD?
- Can you explain a typical CI/CD workflow for ECS, including code build, image build, and deployment?
- How do you manage blue-green or canary deployments in ECS?
- What are some challenges you’ve faced while integrating ECS with CI/CD, and how did you overcome them?
8. ECS with Fargate
- What is AWS Fargate, and how does it simplify ECS management?
- How do you decide whether to use Fargate or EC2 launch types for your ECS tasks?
- Can you explain the pricing model for ECS tasks running on Fargate?
- What are the limitations of using Fargate compared to EC2-backed ECS?
- How do you monitor and troubleshoot Fargate tasks?
9. Monitoring and Logging
- How do you monitor ECS tasks and services?
- What tools do you use for logging and monitoring ECS?
- Can you explain how to set up CloudWatch for ECS task and service monitoring?
- How do you handle log aggregation for ECS containers?
- What are the best practices for setting up alerts and monitoring dashboards for ECS?
10. Advanced ECS Concepts
- How do you manage ECS with AWS CDK or Terraform?
- What is the role of Service Discovery in ECS, and how do you set it up?
- Can you explain the concept of ECS Task Placement Strategies and Constraints?
- How do you manage multi-region deployments with ECS?
- What are the benefits and challenges of using ECS in a microservices architecture?
11. Troubleshooting
- How do you troubleshoot failing ECS tasks?
- What steps do you take when an ECS service is not scaling as expected?
- How do you diagnose and fix networking issues in ECS tasks?
- What tools and methods do you use to investigate performance issues in ECS?
- Can you describe a challenging issue you’ve faced with ECS and how you resolved it?
12. Best Practices
- What are some best practices for deploying applications on ECS?
- How do you ensure high availability and fault tolerance for applications running on ECS?
- What strategies do you use for optimizing cost when using ECS?
- How do you handle application updates and versioning in ECS?
- What are the best practices for securing ECS containers and tasks?