{
  "name": "Docker",
  "versions": [{
      "major_version": "14",
      "minor_version": "04",
      "codename": "trusty",
      "name": "Trusty Tahr",
      "iso_url": "http://archive.ubuntu.com/ubuntu/dists/trusty/main/installer-amd64/current/images/netboot/mini.iso",
      "iso_checksum": "bc09966b54f91f62c3c41fc14b76f2baa4cce48595ce22e8c9f24ab21ac8d965"
    }],
  "boot_command": "install auto=true priority=critical preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}",
  "qemu": {
    "accelerator": "kvm",
    "qemuargs": [ [ "-m", "1024M" ] ]
  },
  "virtualbox": {
    "guest_os_type": "Ubuntu_64",
    "vboxmanage": [ ["modifyvm", "{{.Name}}", "--memory", "1024"] ],
    "guest_additions_mode": "disable"
  }
}