Simplified example of AWS multi-container docker definition for Elastic Beanstalk, including authenticating to external non public docker registry to pull images

Dockerrun.aws.json

{
  "AWSEBDockerrunVersion": 2, /* newer multi container format */
  "authentication": { 
    /* if working with non ECR or non public docker registries, this is required, points to file in S3, 
     that has the correct auth data, this could hold auth for multiple registries, 
     see here: http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/create_deploy_docker.container.console.html#docker-images-private
    */
    "bucket": "s3-bucket-name",
    "key": "prefix"
  },
  "containerDefinitions": [
    {
      "name": "app",
      "image": "docker.jfrog.io/app:latest",

      "environment": [
        {
          "name": "Container",
          "value": "app"
        }
      ],
      "essential": true,
      "memory": 1024,
      "portMappings": [
        {
            "hostPort": 8080,
            "containerPort": 8080
        },
        {
            "hostPort": 8081,
            "containerPort": 8081
        }
      ],

      "mountPoints": [
        {
          "sourceVolume": "awseb-logs-app", /* maps the default container logs folder created by EB/ECS to the internal docker volume */
          "containerPath": "/var/log/"
        }
      ]

    },
    {
      "name": "etcd",
      "image": "microbox/etcd", // public image from docker hub
      "essential": true,
      "memory": 128,
    }    
  ]
}