example.json

{
    "variables" : {
    "aws_access_key": "{{ env `AWS_ACCESS_KEY` }}",
    "aws_secret_key": "{{ env `AWS_SECRET_KEY` }}",
    "iso_url": "./isos/ubuntu-14.04.4-server-amd64.iso",
    "iso_checksum": "2ac1f3e0de626e54d05065d6f549fa3a",
    "iso_checksum_type": "md5"
    },
    "provisioners": [
        {
            "type": "ansible",
            "playbook_file": "./playbook.yml",
            "host_alias": "packerdemo",
            "user": "vagrant",
            "extra_arguments": ["--ask-sudo-pass", "-vv"]
        }
    ],
    "builders": [
        {"type": "amazon-ebs",
        "access_key": "{{ user `aws_access_key`}}",
        "secret_key": "{{ user `aws_secret_key`}}",
        "region": "us-east-1",
        "source_ami": "ami-6d060707",
        "instance_type": "c3.large",
        "ssh_username": "ubuntu",
        "ami_name": "packerdemo {{timestamp}}"
        },
        {"type": "virtualbox-iso",
        "guest_os_type": "Ubuntu_64",
        "iso_url": "{{ user `iso_url` }}",
        "iso_checksum": "{{ user `iso_checksum` }}",
        "iso_checksum_type": "{{ user `iso_checksum_type` }}",
        "ssh_username": "vagrant",
        "ssh_password": "vagrant",
        "headless": "false",
        "ssh_wait_timeout": "1000s",
        "http_directory": "./http/ubuntu",
        "http_port_min": "9321",
        "http_port_max": "9321",
        "shutdown_command": "echo 'vagrant' | sudo -S -E shutdown -P now",
        "boot_command": [
            "<esc><esc><enter><wait>",
            "/install/vmlinuz ",
            "preseed/url=http://{{.HTTPIP}}:{{.HTTPPort}}/preseed.cfg ",
            "debian-installer=en_US auto locale=en_US kbd-chooser/method=us ",
            "hostname={{.Name}} ",
            "fb=false debconf/frontend=noninteractive ",
            "keyboard-configuration/modelcode=SKIP keyboard-configuration/layout=USA ",
            "keyboard-configuration/variant=USA console-setup/ask_detect=false ",
            "initrd=/install/initrd.gz -- <enter>"
            ]
        }
    ],
    "post-processors": [
        {"type": "vagrant",
         "only": ["virtualbox-iso"],
         "output": "./packdemo.box"
        }
    ]
}