Amazon Ecs

  • ECS: Elastic Container Service
    • Is a logical grouping of EC2 machines/instances
    • Is a mere configuration for an efficient use and management of your EC2 instances resources
    • Uses Docker to instantiate containers/instances/virtual machines on these (EC2) hosts
    • To add/register EC2 instances –> all you need is Amazon ECS Container Agent running on your EC2 instance/machine

    Amazon ECS Container Agent

    • The container agent running on each instance within an Amazon ECS cluster sends information about the instance’s current running tasks and resource utilization to Amazon ECS
    • It can start and stop tasks whenever it receives a request from Amazon ECS

What does ECS let you do?

  • Launch & stop container-based applications with simple API calls
  • Get state of your cluster from a centralized service
  • Give access to many familiar Amazon EC2 features
  • Schedule placement of containers across your cluster –> autoscaling group

Containers and Images

  • To deploy applications on Amazon ECS, your application components must be architectured to run in containers
  • Container images are stored in a registry from which they can be downloaded and run on your cluster

Task Definitions

  • To prepare your application to run on Amazon ECS, you create a task definition:
    • Text file - in JSON format
    • Describes one or more containers (max 10) that form your application
    • Is a blueprint for your application
    • Some parameters:
      • Which launch type
      • Which ports
      • What data volumes

Tasks and Scheduling

  • Task:
    • is the instantiation of a task definition within a cluster

  • You can specify the number of tasks to run on your cluster after creating a task definition for your application

  • Scheduler:
    • Place tasks in your cluster
    • There are different scheduling options available - for example, you can define a service that runs and maintains a specified number of tasks simultaneously
  • Clusters:
    • When you run tasks using Amazon ECS, you place them on a cluster, which is a logical grouping of resources
    • Launch type:
      • Fargate: Amazon ECS manages your cluster resources
      • EC2: you manage your group of container instances
Written on May 16, 2018