template.json

{
  "builders": [
    {
      "type": "virtualbox-iso",
      "guest_os_type": "Ubuntu_64",
      "iso_url": "http://releases.ubuntu.com/xenial/ubuntu-16.04.1-server-amd64.iso",
      "iso_checksum": "29a8b9009509b39d542ecb229787cdf48f05e739a932289de9e9858d7c487c80",
      "iso_checksum_type": "sha256",
      "vm_name": "packer-ubuntu-16.04-amd64",
      "disk_size": "{{ user `disk_size` }}",
      "headless": "{{ user `headless` }}",
      "boot_wait": "5s",
      "http_directory": "http",
      "boot_command": [
        "<enter><wait>",
        "<f6><esc>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
        "<bs><bs><bs>",
        "/install/vmlinuz ",
        "initrd=/install/initrd.gz ",
        "auto=true ",
        "priority=critical ",
        "net.ifnames=0 ",
        "url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed.cfg",
        "<wait><enter>"
      ],
      "ssh_wait_timeout": "30m",
      "ssh_username": "vagrant",
      "ssh_password": "vagrant",
      "shutdown_command": "sudo systemctl poweroff",
      "vboxmanage": [
        ["modifyvm", "{{ .Name }}", "--memory", "{{ user `memory` }}"],
        ["modifyvm", "{{ .Name }}", "--cpus", "{{ user `cpus` }}"]
      ]
    }    
  ],
  "provisioners": [
    {
      "type": "shell",
      "scripts": "scripts/install.sh"
    },
    {
      "type": "ansible-local",
      "playbook_file": "ansible/playbook.yml",
      "playbook_dir": "ansible"
    }
  ],
  "post-processors": [
    [
      {
        "type": "vagrant",
        "compression_level": 9,
        "output": "ubuntu-16.04-amd64.box",
        "keep_input_artifact": false
      },
      {
        "type": "atlas",
        "artifact": "s12v/xenial64",
        "artifact_type": "vagrant.box",
        "metadata": {
          "version": "20160904",
          "description": "**Ubuntu 16.04.1 (Xenial Xerus)**. Baked with https://github.com/s12v/xenial\n - Ansible, Puppet, Chef\n - VBoxGuestAdditions 5.0.x\n - 80G disk\n - Predictable network interface names turned off",
          "created_at": "{{timestamp}}",
          "provider": "virtualbox"
        }
      }
    ]
  ],
  "variables": {
    "cpus": "1",
    "memory": "512",
    "hostname": "xenial",
    "headless": "false",
    "disk_size": "81920"
  }
}