Elastic Container Service (ECS)
Welcome to CloudAffaire and this is Debjeet.
In the last AWS blog series, we have discussed Elastic Load Balancing in AWS.
In this blog series we are going to start with a new AWS service Elastic Container Service or ECS.
What is Elastic Container Service (ECS)?
Amazon Elastic Container Service (Amazon ECS) is a highly scalable, fast, container management service that makes it easy to run, stop, and manage Docker containers on a cluster. You can host your cluster on a serverless infrastructure that is managed by Amazon ECS by launching your services or tasks using the Fargate launch type. For more control you can host your tasks on a cluster of Amazon Elastic Compute Cloud (Amazon EC2) instances that you manage by using the EC2 launch type.
Amazon ECS is a regional service that simplifies running application containers in a highly available manner across multiple Availability Zones within a Region. You can create Amazon ECS clusters within a new or existing VPC. After a cluster is up and running, you can define task definitions and services that specify which Docker container images to run across your clusters. Container images are stored in and pulled from container registries, which may exist within or outside of your AWS infrastructure.
Elastic Container Service Launch Types:
Fargate launch type: You can host your cluster on a serverless infrastructure that is managed by Amazon ECS by launching your services or tasks using the Fargate launch type.
EC2 launch type: You can host your tasks on a cluster of Amazon Elastic Compute Cloud (Amazon EC2) instances that you manage by using the EC2 launch type.
Elastic Container Service Components:
To deploy applications on Amazon ECS, your application components must be architected to run in containers. A Docker container is a standardized unit of software development, containing everything that your software application needs to run: code, runtime, system tools, system libraries, etc. Containers are created from a read-only template called an image.
Images are typically built from a Dockerfile, a plain text file that specifies all of the components that are included in the container. These images are then stored in a registry from which they can be downloaded and run on your cluster.
To prepare your application to run on Amazon ECS, you create a task definition. The task definition is a text file, in JSON format, that describes one or more containers, up to a maximum of ten, that form your application. It can be thought of as a blueprint for your application. Task definitions specify various parameters for your application. Examples of task definition parameters are which containers to use, which launch type to use, which ports should be opened for your application, and what data volumes should be used with the containers in the task. The specific parameters available for the task definition depend on which launch type you are using.
A task is the instantiation of a task definition within a cluster. After you have created a task definition for your application within Amazon ECS, you can specify the number of tasks that will run on your cluster.
The Amazon ECS task scheduler is responsible for placing tasks within your cluster. There are several different scheduling options available. For example, you can define a service that runs and maintains a specified number of tasks simultaneously.
When you run tasks using Amazon ECS, you place them on a cluster, which is a logical grouping of resources. When using the Fargate launch type with tasks within your cluster, Amazon ECS manages your cluster resources. When using the EC2 launch type, then your clusters are a group of container instances (EC2) you manage.
The container agent runs on each infrastructure resource within an Amazon ECS cluster. It sends information about the resource’s current running tasks and resource utilization to Amazon ECS, and starts and stops tasks whenever it receives a request from Amazon ECS.
Hope you have enjoyed this article, In the next blog post, we will discuss Cluster in ECS.
To get more details on AWS ECS, please refer below AWS documentation