EC2 Container Service

Build, Run, and Scale

Docker-based applications

Features

• Run any number of docker containers across a managed cluster of EC2 instances
• Run the same Docker daemon that you would run on-premises. 
• Run multiple, unrelated containers on the same EC2 instance in order to make good use of all available resources. 
• Applications can make use of AWS features such as Elastic IP addresses, resource tags, and Virtual Private Cloud (VPC).
• The containers are, in effect, a new base-level building block in the same vein as EC2 and S3.

Container Instance

• Amazon EC2 instance 
• Has docker daemon
• Has amazon ECS Agent

Cluster

• Regional
• Resource Pool
• Grouping of Container Instances
• Start empty, dynamically scalable

Container &Task

• Container – A Docker container that was created as part of a Task
• Task – An instantiation of a Task Definition.
• Task Definition – 
• A description of a set of Containers. 
• The information contained in a Task Description defines one or more Containers.
• All of the Containers defined in a particular Task Definition are run on the same Container Instance
• could be linked or not linked
• could have shared volumes
• container definition names and identifies your image
• includes default runtime attributes for your container

Container Instance & Cluster

• Container Instance –
  • An EC2 instance
  • Runs the ECS Container Agent and that has been registered into a Cluster.
  • The set of instances running within a Cluster create a pool of resources that can be used to run Tasks.
• Cluster – A logical grouping of Container Instances that is used to run Tasks.
  • provides pool of resources to the task
  • grouping of all your container instances
  • starts empty, dynamically scalable

EC2 Container Agent

• Runs on Container Instances.
• Responsible for starting Containers on behalf of ECS.
• Itself runs within a Docker container and communicates with the Docker daemon running on the Instance.
• ECS container agent is available on Docker Hub

Scheduling options

Scheduling refers to the process of assigning tasks to instances

• Automated – The RunTask function will start a Task (as specified by a Task Definition) on a Cluster using random placement.
• Manual – The StartTaskfunction will start a Task (again, as specified by a Task Definition) on a specified Container Instance (or Instances).
• Custom – You can  use the available information to choose a suitable Container Instance and then call StartTask to start a task on the Instance i.e. creating your own implementation of RunTask.

Other Container Management tools

Mesos

Chronos

http://nerds.airbnb.com/introducing-chronos/

References

• http://thenewstack.io
• http://aws.amazon.com/ecs/
• http://panamax.io/
• http://www.infoworld.com/article/2839284/application-virtualization/10-open-source-tools-to-make-docker-even-more-powerful.html#slide2