AWS requires file Dockerrun.aws.json to enable the deployment of multiple Docker containers.

This is part of a series of discussions regarding Deploying TaskMuncher, a React and Node application, to a Multi-Container Docker Environment at AWS using Dockerhub and Travis CI

For more details, please see Overview of Create Multi-Container Docker TaskMuncher Application at AWS

Please review AWS Production Architecture.

Overview

Add the information about the Amazon S3 bucket that contains the authentication file in the authentication parameter of the Dockerrun.aws.json file. Make sure that the authentication parameter contains a valid Amazon S3 bucket and key.

Ensure Upload TaskMuncher Docker .dockercfg to AWS has been completed before proceeding.

Dockerrun

Elastic Beanstalk doesn't know how to run containers and so it hands it off to Amazon Elastic Container Service (ECS).

ECS uses Dockerrun.aws.json, a task definition to run each container.

• Version 1 of the Dockerrun.aws.json format is used to launch a single Docker container to an Elastic Beanstalk environment.
• Version 2 adds support for multiple containers per Amazon EC2 instance and can only be used with the multi-container Docker platform.

Thus use version 2.

Create file Dockerrun.aws.json in base folder of the github repository.

{
  "AWSEBDockerrunVersion": 2,
	"authentication": {
    "bucket": "elasticbeanstalk-us-east-1-971716655829",
    "key": "dockercfg.taskmuncher/.dockercfg"
  },
  "containerDefinitions": [
    {
      "name": "client",
      "image": "johnvincentio/taskmuncher:client",
      "hostname": "client",
      "essential": false,
      "memory": 128
    },
    {
      "name": "server",
      "image": "johnvincentio/taskmuncher:server",
      "hostname": "api",
      "essential": false,
			"links": ["mongodb"],
      "memory": 128
    },
		{
      "name": "mongodb",
      "image": "johnvincentio/taskmuncher:mongodb",
      "hostname": "mongodb",
      "essential": true,
			"portMappings": [
        {
          "hostPort": 27017,
          "containerPort": 27017
        }
      ],
      "memory": 128
    },
    {
      "name": "mongo-client",
      "image": "johnvincentio/taskmuncher:mongo-client",
      "hostname": "mongo-client",
      "essential": false,
			"links": ["mongodb"],
      "memory": 128
    },
    {
      "name": "nginx",
      "image": "johnvincentio/taskmuncher:nginx",
      "hostname": "nginx",
      "essential": true,
      "portMappings": [
        {
          "hostPort": 80,
          "containerPort": 8100
        }
      ],
      "links": ["client", "server"],
      "memory": 128
    }
  ]
}

Each section is a container.

• name is the container name.

• image is the Dockerhub image name to run in this container.

• hostname is the url to use to access this image.

• essential: true means shutdown all containers if this container fails. At least one container must be set to true.

• portMappings, hostPort is the port on the machine that is hosting all of the containers.

• portMappings, containerPort map to this port in this container.

• links is a list of containers that depend on this container. Use the container name, not the hostname.

For example, nginx section links states that the networking should be created to allow the container nginx running image johnvincentio/taskmuncher:nginx to access containers client and server.

Notice

"authentication": {
  "bucket": "elasticbeanstalk-us-east-1-971716655829",
  "key": "dockercfg.taskmuncher/.dockercfg"
}

The values of bucket and key are determined by the Upload TaskMuncher Docker .dockercfg to AWS step.

Amazon Elastic Container Service (ECS) uses Dockerrun.aws.json to configure and run the containers in Elastic Beanstalk.

It is very easy to make mistakes with a json file and, if you make a mistake, AWS will not provide useful help. Thus, always verify this file with a JSON Validator.

References

• Dockerrun.aws.json v2

• Container Definitions

• Amazon ECS Definitions