A Packer template for building a Docker container host on an AWS EC2 instance.

packer-docker-aws.json

{
    "variables": {
        "aws_access_key": "",
        "aws_secret_key": ""
    },
    "builders": [
        {
            "type": "amazon-ebs",
            "access_key": "{{user `aws_access_key`}}",
            "secret_key": "{{user `aws_secret_key`}}",
            "region": "us-east-1",
            "source_ami": "ami-663a6e0c",
            "instance_type": "m3.xlarge",
            "ssh_username": "ubuntu",
            "ami_name": "packer-docker",
            "ami_description": "Used as a base server for running containers",
            "tags": {
                "Role": "docker",
                "Built": "{{timestamp}}"
            },
            "ami_block_device_mappings": [
                {
                    "device_name": "/dev/sdf",
                    "volume_size": "100",
                    "virtual_name": "EBS-1"
                }
            ]
        }
    ],
    "provisioners": [
        {
            "type": "shell",
            "inline": [
                "echo 'wait-for-core-services'",
                "sleep 10"
            ]
        },
        {
            "type": "shell",
            "inline": [
                "echo 'docker-prerequisites'",
                "sudo apt-get update -qq",
                "sudo apt-get install -qq apt-transport-https ca-certificates",
                "sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D",
                "echo 'deb https://apt.dockerproject.org/repo ubuntu-trusty main' | sudo tee /etc/apt/sources.list.d/docker.list",
                "sudo apt-get update -qq",
                "sudo apt-get purge lxc-docker",
                "sudo apt-cache policy docker-engine",
                "sudo apt-get -qq install linux-image-extra-$(uname -r) apparmor"
            ]
        },
        {
            "type": "shell",
            "inline": [
                "echo 'docker-install'",
                "sudo apt-get update -qq",
                "sudo apt-get install -qq docker-engine"
            ]
        },
        {
            "type": "shell",
            "inline": [
                "echo 'docker-add-user-to-group'",
                "sudo usermod -aG docker ubuntu"
            ]
        },
        {
            "type": "shell",
            "inline": [
                "echo 'docker-configure-dns'",
                "echo 'DOCKER_OPTS=\"--dns 8.8.8.8 --dns 8.8.4.4\"' | sudo tee /etc/default/docker",
                "sudo service docker restart"
            ]
        },
        {
            "type": "shell",
            "inline": [
                "echo 'reboot'",
                "sudo reboot"
            ]
        },
        {
            "type": "shell-local",
            "command": "sleep 60"
        }
    ]
}

This Packer template is used for building a base box on AWS that can then host containers. I follow the Docker installation instructions for Installation on Ubuntu. It can be used as follows:

packer build --var 'aws_access_key=<YOUR_ACCESS_KEY>' --var 'aws_secret_key=<YOUR_SECRET_KEY>' .\packer-docker-aws.json

Add additional provisioners after the last one for whatever containers/additional packages you might want to run.