Amazon ECS Interview Questions
What is Amazon Elastic Container Service?
Amazon Elastic Container Service (ECS) is a fully managed container orchestration service provided by Amazon Web Services (AWS). It allows you to easily deploy, manage, and scale containerized applications using Docker containers.
Why should I use Amazon ECS?
Amazon ECS simplifies the management of containerized applications. It provides features like load balancing, scaling, and automated updates, making it an ideal choice for deploying and managing containerized workloads in a highly available and scalable manner.
How is Amazon ECS different from AWS Lambda?
Amazon ECS and AWS Lambda are both serverless compute services, but they serve different purposes. ECS is designed for running long-lived containerized applications, while Lambda is for executing event-driven, short-lived functions without the need to manage infrastructure.
What is the pricing for Amazon ECS?
The pricing for Amazon ECS depends on various factors such as the type of launch type (EC2 or Fargate), the region, and the specific resources you use. You pay for the compute resources (e.g., EC2 instances) and any other AWS resources used in your ECS setup.
How is Amazon ECS different from AWS Elastic Beanstalk?
Amazon ECS is a container orchestration service, whereas AWS Elastic Beanstalk is a Platform as a Service (PaaS) offering. ECS provides more control over container management, while Elastic Beanstalk abstracts infrastructure and provides a platform for deploying web applications.
Does Amazon ECS support any other container types?
Amazon ECS primarily supports Docker containers. You can package and run applications using Docker images. Other container types may not be directly supported but can be managed if they can be packaged into Docker containers.
I want to launch ECS Containers. Why do I have to launch tasks?
In Amazon ECS, tasks are the fundamental unit of work, and they define the work that needs to be done. Tasks are typically composed of one or more containers. Launching tasks allows you to specify how your containers should run, including resource requirements and dependencies.
Does Amazon ECS support batch jobs?
Yes, Amazon ECS supports batch-processing workloads. You can use ECS to manage and scale batch jobs by defining tasks that run containers for your batch processing needs.
Can I use my own scheduler with Amazon ECS?
Yes, Amazon ECS allows you to use your own scheduler. You can create custom scheduling logic or integrate third-party schedulers with ECS using the ECS task placement strategies.
Can I use my own Amazon Machine Image (AMI)?
If you are using the EC2 launch type in Amazon ECS, you can use your own Amazon Machine Images (AMIs) to customize the instances where your containers run.
Does Amazon ECS support applications and services?
Yes, Amazon ECS supports both applications and services. You can define and manage applications and services using ECS to ensure high availability and scalability for your containerized workloads.
Does Amazon ECS support dynamic port mapping?
Yes, Amazon ECS supports dynamic port mapping. When using the EC2 launch type, ECS can dynamically assign a port for your container if you don't specify a fixed port in your task definition.
How should I choose between using AWS Fargate with Amazon ECS or just using ECS?
The choice between AWS Fargate and the EC2 launch type in Amazon ECS depends on your specific requirements. Fargate is a serverless compute engine, while the EC2 launch type provides more control over the underlying infrastructure. The decision depends on factors like cost, control, and operational preferences.
How can I configure my container instances to pull from Amazon Elastic Container Registry?
You can configure your container instances to pull Docker images from the Amazon Elastic Container Registry (ECR) by attaching the necessary permissions and authentication credentials to your instances. This ensures that your containers can access the images stored in your ECR repositories.
How does AWS Fargate work with Amazon ECS?
AWS Fargate is a launch type for Amazon ECS that allows you to run containers without managing the underlying infrastructure. Fargate provisions the required resources for your containers, making it a convenient choice for serverless container workloads in ECS.
Questions on Amazon ECS Security and Compliance
How does Amazon ECS isolate containers belonging to different customers?
Amazon ECS isolates containers belonging to different customers by running them in separate clusters, Virtual Private Clouds (VPCs), or using other network isolation mechanisms. This ensures that containers from different customers are separated and cannot access each other's resources.
How do I configure IAM roles for ECS tasks?
You can configure IAM roles for Amazon ECS tasks by creating IAM roles with the necessary permissions and attaching them to your ECS task definitions. These roles control what resources and services your ECS tasks can access.
With which compliance programs do Amazon ECS conform?
Amazon ECS conforms to various compliance programs, including HIPAA, FedRAMP, and others. The level of compliance may vary depending on how you configure and use ECS.
Can I use Amazon ECS for Protected Health Information (PHI) and other HIPAA-regulated workloads?
Yes, you can use Amazon ECS for PHI and other HIPAA-regulated workloads, but you need to ensure compliance by setting up your ECS cluster in a dedicated HIPAA-compliant VPC, using IAM policies, and encrypting PHI. AWS provides the tools, but it's your responsibility to meet HIPAA requirements.
Can I operate container instances with different security settings or segregate different tasks across different environments?
Yes, you can operate Amazon ECS container instances with different security settings and segregate tasks across different environments. The approach varies depending on the launch type (ECS, Fargate, EKS, Outposts) you use and the security and isolation requirements you have.
Does Amazon ECS support retrieving Docker images from a private or internal source?
Yes, Amazon ECS supports retrieving Docker images from private or internal sources. You can configure ECS to access Docker images stored in private or internal registries, including Amazon Elastic Container Registry (ECR) and other private repositories.
Can I use Amazon ECS for US Government-regulated workloads or processing sensitive Controlled Unclassified Information (CUI)?
Yes, you can use Amazon ECS for US Government-regulated workloads or processing sensitive Controlled Unclassified Information (CUI) by setting up a dedicated VPC, using IAM policies, encrypting CUI, and ensuring compliance with government requirements.
Questions on Amazon ECS Service Level Agreement (SLA)
How do I know if I qualify for an SLA Service Credit?
To qualify for an SLA Service Credit in Amazon ECS, you must follow specific steps, including having a valid ECS SLA Service Level Agreement Credit Request form, notifying AWS of service failures, and meeting the criteria for service credit eligibility.
What does the Amazon ECS SLA guarantee?
The Amazon ECS Service Level Agreement (SLA) guarantees a certain level of uptime, performance, and response times for the service. It outlines the expected monthly uptime percentage, performance levels, and response times that AWS commits to maintaining for ECS. Service credits may be applicable if these guarantees are not met due to AWS's issues.