ECS Interview Questions

1. What is Amazon Elastic Container Service?

mazon Elastic Container Service (Amazon ECS) is a fully-managed container orchestration service that makes it easy to run, scale, and manage containerized applications. It allows you to define and run containerized workloads using Docker containers, and it provides a number of features to help you build, deploy, and manage your applications.

Some key features of Amazon ECS include:

1. Container orchestration: Amazon ECS provides tools and features for scheduling and managing containers across a cluster of Amazon EC2 instances. You can use Amazon ECS to deploy and scale your containers, as well as to monitor their health and performance.
2. Container registry: Amazon ECS integrates with the Amazon Elastic Container Registry (Amazon ECR) to allow you to store and manage your Docker images. You can use Amazon ECR to build, store, and deploy container images, as well as to manage their lifecycle and access controls.
3. Integration with other AWS services: Amazon ECS integrates with a number of other AWS services, including Amazon EC2, Amazon RDS, and Amazon S3, to allow you to build and deploy containerized applications that leverage these services.

Overall, Amazon ECS is a powerful and flexible tool for managing containerized applications on the AWS platform. It is designed to make it easy to build, deploy, and manage containerized applications, and it provides a number of tools and features to help you scale and operate your applications in a reliable and cost-effective manner.

2. Why should I use Amazon ECS?

There are a number of reasons why you might want to use Amazon Elastic Container Service (Amazon ECS) to manage your containerized applications:

1. Fully-managed service: Amazon ECS is a fully-managed service, which means that you don’t have to worry about managing the underlying infrastructure or infrastructure scaling. Amazon ECS takes care of the heavy lifting for you, allowing you to focus on building and deploying your applications.
2. Integration with other AWS services: Amazon ECS integrates with a number of other AWS services, such as Amazon EC2, Amazon RDS, and Amazon S3, allowing you to build and deploy containerized applications that leverage these services. This can save you time and effort when building and deploying your applications, as you don’t have to worry about managing the underlying services yourself.
3. Scalability: Amazon ECS makes it easy to scale your containerized applications up or down as needed. You can use Amazon ECS to automatically scale your containers based on demand, or you can manually scale your containers as needed.
4. Security: Amazon ECS provides a number of security features to help you protect your applications and data. For example, Amazon ECS integrates with Amazon Virtual Private Cloud (Amazon VPC) to allow you to build and deploy your applications in a secure and isolated environment.
5. Cost-effective: Amazon ECS provides a pay-as-you-go pricing model, which means that you only pay for the resources you use. This can help you reduce costs and optimize your application’s performance.

Overall, Amazon ECS is a powerful and flexible tool for managing containerized applications on the AWS platform. It is designed to make it easy to build, deploy, and manage containerized applications, and it provides a number of tools and features to help you scale and operate your applications in a reliable and cost-effective manner.

3. How is Amazon ECS different from AWS Lambda?

Amazon Elastic Container Service (Amazon ECS) and AWS Lambda are two different types of cloud computing services provided by Amazon Web Services (AWS). Here are a few key differences between the two services:

1. Purpose: Amazon ECS is a container orchestration service that is designed to run, scale, and manage containerized applications. AWS Lambda is a serverless computing platform that is designed to run code in response to specific events.
2. Resource management: Amazon ECS allows you to define and manage a set of containers that run your code. You can specify the number and type of containers you want to run, as well as how they should be deployed and scaled. With AWS Lambda, you don’t have to worry about managing the underlying resources – you just specify the code you want to run and AWS Lambda takes care of the rest.
3. Scaling: Amazon ECS allows you to scale your containers up or down as needed. You can use Amazon ECS to automatically scale your containers based on demand, or you can manually scale your containers as needed. AWS Lambda automatically scales to meet the demands of your applications, and you don’t have to worry about scaling the underlying infrastructure.
4. Pricing: Amazon ECS charges you for the resources you use to run your containers, such as the number and type of Amazon EC2 instances you use. AWS Lambda charges you for the number of requests your functions receive and the time

4. What is the pricing for Amazon ECS?

The pricing for Amazon Elastic Container Service (Amazon ECS) depends on the resources you use to run your containerized applications, as well as the specific features and services you use.

Here are a few examples of the types of costs you might incur when using Amazon ECS:

1. Amazon EC2 instances: Amazon ECS runs your containers on Amazon EC2 instances. You will be charged for the number and type of instances you use, as well as for the amount of time you use them.
2. Amazon Elastic Container Registry (Amazon ECR): Amazon ECR is a fully-managed container registry service that is used to store, manage, and deploy Docker images. You will be charged for the number of images you store and the number of pulls you make from the registry.
3. Load balancing: Amazon ECS supports load balancing using the Amazon Elastic Load Balancer (ELB). You will be charged for the use of the ELB based on the number of requests it handles and the amount of data it transfers.
4. Data transfer: Amazon ECS charges for data transfer to and from the internet and between different AWS regions.

Overall, the pricing for Amazon ECS is based on the resources you use to run your containerized applications. You can use the AWS Pricing Calculator to estimate the cost of using Amazon ECS for your specific needs.

5. How is Amazon ECS different from AWS Elastic Beanstalk?

Amazon Elastic Container Service (Amazon ECS) and AWS Elastic Beanstalk are two different types of cloud computing services provided by Amazon Web Services (AWS). Here are a few key differences between the two services:

1. Purpose: Amazon ECS is a container orchestration service that is designed to run, scale, and manage containerized applications. AWS Elastic Beanstalk is a fully-managed service that makes it easy to deploy and run web applications and services.
2. Resource management: Amazon ECS allows you to define and manage a set of containers that run your code. You can specify the number and type of containers you want to run, as well as how they should be deployed and scaled. With AWS Elastic Beanstalk, you don’t have to worry about managing the underlying resources – you just specify the code you want to run and AWS Elastic Beanstalk takes care of the rest.
3. Deployment: Amazon ECS allows you to deploy your containers using a variety of methods, such as Amazon ECS services, AWS Fargate, or Amazon EC2 instances. AWS Elastic Beanstalk provides a range of options for deploying your applications, including deploying to Amazon EC2 instances, AWS Lambda, or on-premises servers.
4. Monitoring and logging: Amazon ECS provides tools and features for monitoring and logging the health and performance of your containers. AWS Elastic Beanstalk provides tools for monitoring and logging the health and performance of your applications, as well as alerts and notifications to help you identify and resolve issues.

Overall, while Amazon ECS and AWS Elastic Beanstalk are both designed to help you deploy and run applications, they are geared towards different types of workloads and provide different sets of features and capabilities. You should choose the service that best meets your needs based on your specific requirements and goals.

6. Does Amazon ECS support any other container types?

Amazon Elastic Container Service (Amazon ECS) is a fully-managed container orchestration service that allows you to run, scale, and manage containerized applications using Docker containers. Amazon ECS supports the use of Docker containers, which are the most widely used container format.

While Amazon ECS does not natively support other container formats, such as OCI (Open Container Initiative) containers, you can use Docker to run containers in other formats. For example, you can use Docker to build and run OCI containers on Amazon ECS by following the appropriate steps.

Overall, while Amazon ECS primarily supports the use of Docker containers, it is possible to use other container formats with the service by using Docker as an intermediary. You can use the tools and features provided by Amazon ECS to manage and orchestrate your containers, regardless of the container format you choose to use.

7. I want to launch ECS Containers. Why do I have to launch tasks?

In Amazon Elastic Container Service (ECS), a task is a defined unit of work that is processed by the ECS service. You can think of a task as an executable application package that is run on an Amazon EC2 instance or on a Fargate compute environment.

Tasks are used to run Docker containers in ECS. When you launch a task, you specify which container image to use and which command to run inside the container. You can also specify other details such as the number of CPU and memory resources to allocate to the task, the environment variables to pass to the container, and the IAM role to use for the task.

By launching tasks, you can run multiple instances of a containerized application on ECS. This can be useful for scaling up your application to handle increased traffic, or for running multiple copies of the same application for high availability.

ECS also provides other features such as load balancing and service discovery that are built on top of tasks, which can help you manage and orchestrate your containerized applications in a more automated and scalable way.

8. Does Amazon ECS support batch jobs?

Yes, Amazon Elastic Container Service (ECS) does support batch jobs. Batch jobs are a common use case for ECS, as it allows you to run compute-intensive workloads in a scalable and reliable way.

To run a batch job on ECS, you can create a task definition that specifies the container image to use and the command to run inside the container. You can then use the ECS API or the AWS Management Console to launch a one-time task, or you can use Amazon CloudWatch Events to schedule the task to run on a recurring basis.

ECS provides integration with Amazon CloudWatch Events, which allows you to set up rules to trigger the execution of tasks on a schedule. This can be useful for running batch jobs that need to be run at regular intervals, such as daily or weekly backups, data processing jobs, or other types of scheduled tasks.

ECS also provides integration with other AWS services such as AWS Batch, which is a fully-managed service for running batch computing workloads. AWS Batch can be used to run batch jobs on ECS, and it provides additional features such as automatic scaling, job dependencies, and resource optimization.

9. Can I use my own scheduler with Amazon ECS?

Yes, you can use your own scheduler with Amazon Elastic Container Service (ECS). ECS provides a number of APIs and tools that you can use to launch and manage tasks, which allows you to integrate ECS with your own scheduling system.

One way to use your own scheduler with ECS is to use the ECS API to launch tasks. You can use the RunTask API action to launch a task on ECS, and you can specify the task definition, the number of tasks to launch, and the Amazon EC2 instances or Fargate compute environments on which to run the tasks. You can use this API to launch tasks in response to events or as part of a custom scheduling system.

Another option is to use the ECS CLI or the AWS SDKs to launch tasks from your own scheduling system. The ECS CLI provides command-line tools for interacting with the ECS API, and the AWS SDKs provide libraries for various programming languages that you can use to build custom applications that interact with ECS.

ECS also provides integration with other AWS services such as AWS Batch, which is a fully-managed service for running batch computing workloads. AWS Batch can be used to run batch jobs on ECS, and it provides features such as job dependencies and resource optimization. You can use AWS Batch to submit and manage batch jobs, and you can use the AWS Batch API or the AWS Management Console to view the status of your jobs.

10. Can I use my own Amazon Machine Image (AMI)?

Yes, you can use your own Amazon Machine Image (AMI) with Amazon Elastic Container Service (ECS). An AMI is a pre-configured virtual machine image that contains the operating system and other software needed to launch an instance on Amazon Elastic Compute Cloud (EC2).

When you launch an ECS task, you can specify an AMI to use for the EC2 instances on which the task will run. ECS supports a variety of AMI types, including Amazon Linux, Ubuntu, and Windows, as well as custom AMIs that you create yourself.

To use a custom AMI with ECS, you will need to create the AMI using the EC2 console, the EC2 API, or a command-line tool such as the AWS CLI. You will also need to ensure that the AMI is properly configured and that it includes the necessary software and libraries to run your containers.

Once you have created and configured your custom AMI, you can specify it when you create an ECS task definition. In the task definition, you can specify the AMI ID and any other details such as the instance type, the IAM role, and the security group to use for the instances.

When you launch a task, ECS will launch one or more EC2 instances using the specified AMI, and it will run the task on those instances. You can use the ECS console, the ECS API, or the ECS CLI to launch tasks and view the status of your tasks and instances.

11. Does Amazon ECS support applications and services?

Yes. The Amazon ECS Service scheduler can manage long-running applications and services. The service scheduler helps you maintain application availability and allows you to scale your containers up or down to meet your application’s capacity requirements. The service scheduler allows you to distribute traffic across your containers using Elastic Load Balancing (ELB). Amazon ECS will automatically register and deregister your containers from the associated load balancer.

The service scheduler will also automatically recover containers that become unhealthy (i.e. fail ELB health checks) or stop running to ensure you have the desired number of healthy containers supporting your application.

You can scale your application up and down by changing the number of containers you want the service to run. You can update your application by changing its definition or using a new image. The scheduler will automatically start new containers using the new definition and stop containers running the previous version (waiting for the ELB connections to drain if ELB is used).

12. Does Amazon ECS support dynamic port mapping?

Yes, Amazon Elastic Container Service (ECS) does support dynamic port mapping for containers. When you run a task that includes a container with dynamic port mapping, ECS allocates a host port for the container and maps it to a container port. The port mapping is dynamic in the sense that ECS assigns an available host port to the container at runtime, rather than requiring you to specify a specific host port when you create the task.

To use dynamic port mapping in ECS, you can specify the hostPort value as 0 in the task definition for the container. This tells ECS to allocate an available host port for the container when the task is run. You can then access the container through the allocated host port.

Here’s an example of how to specify dynamic port mapping in a task definition:

{
  "containerDefinitions": [
    {
      "name": "my-container",
      "image": "my-image:latest",
      "portMappings": [
        {
          "containerPort": 80,
          "hostPort": 0
        }
      ]
    }
  ]
}

In this example, ECS will allocate an available host port when the task is run, and map it to the container’s port 80. You can then access the container through the allocated host port.

Keep in mind that dynamic port mapping is only supported for tasks using the EC2 launch type. It is not supported for tasks using the Fargate launch type.

13. How should I choose between using AWS Fargate with Amazon ECS or just using ECS?

AWS Fargate is a compute engine for Amazon Elastic Container Service (ECS) that allows you to run containers without the need to manage the underlying EC2 instances. This can make it easier to get started with ECS, as you don’t have to worry about provisioning and managing the EC2 instances that your containers will run on.

There are a few factors to consider when deciding whether to use Fargate with ECS or just use ECS:

1. Cost: Fargate charges a higher price per vCPU and per GB of memory compared to running ECS on EC2 instances. However, Fargate can be more cost-effective if you have a large number of small, short-lived tasks, as you don’t have to pay for the EC2 instances when the tasks are not running.
2. Flexibility: ECS on EC2 offers more flexibility in terms of how you can customize the underlying instances and the operating system. For example, you can choose the instance type, configure the storage, and install additional software on the instances. With Fargate, you don’t have this level of control over the underlying infrastructure.
3. Resource utilization: ECS on EC2 allows you to optimize resource utilization by running multiple tasks on the same instance and using features like EC2 Auto Scaling. With Fargate, you are limited to the resources allocated to your tasks, and you cannot over-provision resources.
4. Development workflow: Fargate can simplify the development workflow by eliminating the need to manage the underlying EC2 instances. This can be particularly helpful if you have a small team or if you are new to ECS.

Ultimately, the choice between using Fargate with ECS or just using ECS will depend on your specific needs and requirements. You should consider factors like cost, flexibility, resource utilization, and your development workflow when making a decision.

14. How can I configure my container instances to pull from Amazon Elastic Container Registry?

To configure your container instances to pull container images from Amazon Elastic Container Registry (ECR), you will need to do the following:

1. Create an Amazon ECR repository and push your container images to it. You can do this using the aws ecr command-line interface (CLI), or through the Amazon ECR console.
2. On the container instances where you want to pull the images from Amazon ECR, install the aws CLI and configure it with the credentials of an IAM user or role that has permission to access the Amazon ECR repository.
3. Use the aws ecr get-login command to obtain an authentication token that you can use to log in to the Amazon ECR registry from your container instance.
4. Run the docker login command on your container instance, using the authentication token obtained in the previous step. This will allow the container instance to pull images from the Amazon ECR repository.
5. To pull an image from the Amazon ECR repository, use the docker pull command and specify the full URI of the image in the repository, including the registry and repository name. For example:

docker pull <aws_account_id>.dkr.ecr.<region>.amazonaws.com/<repository_name>:<tag>

Note that you will need to replace <aws_account_id>, <region>, <repository_name>, and <tag> with the appropriate values for your Amazon ECR repository.

15. How does AWS Fargate work with Amazon ECS?

AWS Fargate is a compute engine for Amazon Elastic Container Service (ECS) that allows you to run containers without having to manage the underlying EC2 instances. With Fargate, you can focus on building and running your applications, rather than worrying about the infrastructure required to run them.

When you use Fargate with Amazon ECS, you specify the amount of CPU and memory that you want to allocate to your containers, and Fargate launches the containers on your behalf, using the Amazon Elastic Container Service for Kubernetes (EKS) or the EC2 launch type. You can specify which containers should be run on Fargate using task definitions, which define the resources and command to run for each container.

You can also use Fargate with Amazon Elastic Container Service for Kubernetes (EKS) to run your Kubernetes workloads on Fargate. This allows you to use the same tooling and APIs that you would use for running your workloads on EC2, but without having to manage the underlying infrastructure.

Questions on Amazon ECS Security and Compliance

16. How does Amazon ECS isolate containers belonging to different customers?

Amazon ECS schedules containers for execution on customer-controlled Amazon EC2 instances or with AWS Fargate and builds on the same isolation controls and compliance settings available for EC2 customers. Your compute instances are located in a Virtual Private Cloud (VPC) with an IP range that you specify. You decide which instances are exposed to the Internet and which remain private.

• Your EC2 instances use an IAM role to access the ECS service.
• Your ECS tasks use an IAM role to access services and resources.
• Security Groups and networks ACLs allow you to control inbound and outbound network access to and from your instances.
• You can connect your existing IT infrastructure to resources in your VPC using industry-standard encrypted IPsec VPN connections.
• You can provision your EC2 resources as Dedicated Instances. Dedicated Instances are Amazon EC2 Instances that run on hardware dedicated to a single customer for additional isolation.

17. How do I configure IAM roles for ECS tasks?

To configure IAM roles for Amazon Elastic Container Service (ECS) tasks, you will need to do the following:

1. Create an IAM role with the necessary permissions for the task. This role should have the permissions required to access any AWS resources that the task will need to use.
2. In the ECS task definition, specify the IAM role that you created in the previous step as the task execution role. This will allow the task to assume the role and use its permissions when it is running.
3. If the task needs to assume additional IAM roles in order to access other resources, you can specify these roles as task-level IAM roles in the task definition. These roles will be assumed by the task in addition to the task execution role.
4. If your task is running on an EC2 instance that was launched with an IAM role, you can also specify that role as the container instance IAM role in the task definition. This will allow the task to assume the container instance role in addition to the task execution role and any task-level IAM roles.

Here is an example task definition that specifies an IAM role for a task:

{
  "executionRoleArn": "arn:aws:iam::012345678901:role/ecsTaskExecutionRole",
  "containerDefinitions": [
    {
      "name": "my-task",
      "image": "amazon/amazon-ecs-sample",
      "cpu": 1024,
      "memory": 2048,
      "essential": true
    }
  ],
  "family": "my-task-family"
}

18. With which compliance programs do Amazon ECS conform?

Amazon Elastic Container Service (ECS) conforms to a number of compliance programs, including the following:

1. PCI DSS: ECS is compliant with the Payment Card Industry Data Security Standard (PCI DSS), which is a set of security standards designed to ensure the safe handling of credit card information.
2. HIPAA: ECS is compliant with the Health Insurance Portability and Accountability Act (HIPAA), which is a set of regulations that govern the use and disclosure of protected health information.
3. SOC: ECS is compliant with the Service Organization Control (SOC) framework, which is a set of standards for evaluating the internal controls of a service organization.
4. ISO 27001: ECS is compliant with the ISO 27001 standard, which is a set of guidelines for managing and protecting sensitive information.
5. GDPR: ECS is compliant with the General Data Protection Regulation (GDPR), which is a set of regulations that govern the collection, use, and protection of personal data.
6. FedRAMP: ECS is compliant with the Federal Risk and Authorization Management Program (FedRAMP), which is a set of security standards for cloud services used by the US government.

19. Can I use Amazon ECS for Protected Health Information (PHI) and other HIPAA-regulated workloads?

Yes, you can use Amazon Elastic Container Service (ECS) to run Protected Health Information (PHI) and other HIPAA-regulated workloads. ECS is a fully managed container orchestration service that makes it easy to run and scale containerized applications.

To use ECS for PHI and other HIPAA-regulated workloads, you will need to do the following:

1. Set up your Amazon ECS cluster in an Amazon Virtual Private Cloud (VPC) that is dedicated to HIPAA-regulated workloads. This will ensure that the cluster and the containers running on it are isolated from other workloads and are only accessible to authorized users.
2. Use IAM policies and resource-level permissions to control access to the cluster and the containers running on it. This will help ensure that only authorized users can access the PHI.
3. Configure your containers to encrypt any PHI that is stored or transmitted by the container. This will help protect the PHI from unauthorized access.
4. Regularly review and update your security controls to ensure that they are in compliance with HIPAA requirements.

Please note that while ECS is compliant with HIPAA, it is your responsibility to ensure that your use of ECS is compliant with HIPAA and other applicable regulations.

20. Can I operate container instances with different security settings or segregate different tasks across different environments?

Yes, you can operate Amazon Elastic Container Service (ECS) container instances with different security settings, or segregate different tasks across different environments. There are a few different ways you can do this:

1. Use Amazon Elastic Container Service for Kubernetes (EKS) to run your tasks. With EKS, you can use Kubernetes namespaces and resource quotas to segment your tasks and control access to resources.
2. Use Amazon Elastic Container Service (ECS) with the EC2 launch type. With this launch type, you can launch your container instances in different Amazon Virtual Private Clouds (VPCs) or subnets, and use security groups and network ACLs to control access to the instances.
3. Use ECS with the Fargate launch type. With Fargate, you can specify the VPC and subnets where your tasks should be run, and use security groups to control access to the tasks.
4. Use ECS with the AWS Outposts launch type. With Outposts, you can run your tasks on physical servers that are located on your own premises, which allows you to operate your tasks in a physically isolated environment.

21. Does Amazon ECS support retrieving Docker images from a private or internal source?

Yes, Amazon Elastic Container Service (ECS) supports retrieving Docker images from a private or internal source. You can use ECS with the EC2 or Fargate launch type to pull images from a private Docker registry, such as a registry running on an EC2 instance or an on-premises registry.

To use a private registry with ECS, you will need to do the following:

1. Install and configure the Docker daemon on your container instances.
2. Use the aws ecr get-login command to obtain an authentication token that you can use to log in to the registry from your container instance.
3. Run the docker login command on your container instance, using the authentication token obtained in the previous step. This will allow the container instance to pull images from the registry.
4. In your task definition, specify the full URI of the image in the registry, including the registry hostname and the repository and tag names.

Here is an example task definition that retrieves an image from a private registry:

{
  "containerDefinitions": [
    {
      "name": "my-task",
      "image": "my-private-registry.example.com/my-repository:my-tag",
      "cpu": 1024,
      "memory": 2048,
      "essential": true
    }
  ],
  "family": "my-task-family"
}

22. Can I use Amazon ECS for US Government-regulated workloads or processing sensitive Controlled Unclassified Information (CUI)?

Yes, you can use Amazon Elastic Container Service (ECS) to run US Government-regulated workloads or process sensitive Controlled Unclassified Information (CUI). ECS is a fully managed container orchestration service that makes it easy to run and scale containerized applications.

To use ECS for US Government-regulated workloads or CUI, you will need to do the following:

1. Set up your Amazon ECS cluster in an Amazon Virtual Private Cloud (VPC) that is dedicated to US Government-regulated workloads or CUI. This will ensure that the cluster and the containers running on it are isolated from other workloads and are only accessible to authorized users.
2. Use IAM policies and resource-level permissions to control access to the cluster and the containers running on it. This will help ensure that only authorized users can access the CUI.
3. Configure your containers to encrypt any CUI that is stored or transmitted by the container. This will help protect the CUI from unauthorized access.
4. Regularly review and update your security controls to ensure that they are in compliance with US Government requirements.

Please note that while ECS is compliant with a number of regulations, including FedRAMP, it is your responsibility to ensure that your use of ECS is compliant with all applicable regulations.

Questions on Amazon ECS Service Level Agreement (SLA)

23. How do I know if I qualify for an SLA Service Credit?

Amazon Elastic Container Service (ECS) provides a Service Level Agreement (SLA) that guarantees a certain level of uptime for the service. If ECS does not meet the uptime guarantee, you may be eligible for a Service Credit, which is a monetary credit that is applied to your AWS bill.

To qualify for an SLA Service Credit, you must meet the following requirements:

1. You must have a valid ECS Service Level Agreement Credit Request form. You can request this form from AWS Support.
2. The ECS service must have experienced a failure that is covered by the ECS SLA. The ECS SLA covers failures that result in the ECS service being unavailable or impaired, as well as failures that result in a degradation of performance below the specified performance levels.
3. You must have notified AWS of the service failure within the specified time frame. You can notify AWS of a service failure by opening a support case in the AWS Support Center.
4. The service failure must have lasted for a certain minimum duration. The minimum duration varies depending on the severity of the service failure.

If you believe that you qualify for an SLA Service Credit, you can submit a request through the AWS Support Center. AWS will review your request and, if approved, apply the credit to your AWS bill.

24. What does the Amazon ECS SLA guarantee?

The Amazon Elastic Container Service (ECS) Service Level Agreement (SLA) guarantees a certain level of uptime for the service. Specifically, the ECS SLA guarantees the following:

1. Monthly Uptime Percentage: The ECS SLA guarantees a certain percentage of uptime for the service each month. This percentage is calculated as the total number of minutes that the service was available during the month, divided by the total number of minutes in the month. If the service does not meet the uptime guarantee, you may be eligible for a Service Credit, which is a monetary credit that is applied to your AWS bill.
2. Performance Levels: The ECS SLA also guarantees certain performance levels for the service. These performance levels vary depending on the region in which the service is used and the type of service you are using (e.g., EC2 or Fargate). If the service does not meet the performance guarantees, you may be eligible for a Service Credit.
3. Response Times: The ECS SLA guarantees certain response times for service requests made through the AWS Support Center. If AWS does not meet the response time guarantees, you may be eligible for a Service Credit.

Please note that the ECS SLA does not cover failures or performance issues that are caused by factors outside of AWS’s control, such as network disruptions or outages, or issues with your own applications or infrastructure.