template.json

{
  "builders": [
    {
      "type": "virtualbox-iso",
      "name": "virtualbox-null-clean",
      "vm_name": "ubuntu2004-virtualbox",
      "iso_urls": [
        "ubuntu-20.04.5-live-server-amd64.iso",
        "https://old-releases.ubuntu.com/releases/20.04/ubuntu-20.04.5-live-server-amd64.iso"
      ],
      "iso_checksum": "sha256:5035be37a7e9abbdc09f0d257f3e33416c1a0fb322ba860d42d74aa75c3468d4",
      "disk_size": "8192",
      "hard_drive_interface": "sata",
      "format": "ova",
      "output_directory": "build",
      "vboxmanage": [
        ["modifyvm", "{{.Name}}", "--memory", "1024"],
        ["modifyvm", "{{.Name}}", "--cpus", "2"]
      ],
      "headless": "true",
      "guest_additions_mode": "disable",
      "guest_os_type": "Ubuntu_64",
      "http_directory": "http",
      "vrdp_bind_address": "0.0.0.0",
      "vrdp_port_min": "5901",
      "vrdp_port_max": "5901",
      "communicator": "ssh",
      "ssh_username": "ubuntu",
      "ssh_password": "ubuntu",
      "ssh_timeout": "1h",
      "ssh_handshake_attempts": "99999",
      "boot_wait": "1s",
      "boot_keygroup_interval": "1s",
      "boot_command": [
        "<tab><wait><tab><wait><tab><wait><tab><wait>",
        "<tab><wait><tab><wait><tab><wait><tab><wait>",
        "<tab><wait><tab><wait><tab><wait><tab><wait>",
        "<esc><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>",
        "/casper/vmlinuz autoinstall quiet net.ifnames=0 biosdevname=0 ds=nocloud-net;s=http://{{ .HTTPIP }}:{{ .HTTPPort }}/ ",
        "initrd=/casper/initrd ",
        " --- <enter>"
      ],
      "shutdown_timeout": "5m",
      "shutdown_command": "echo 'ubuntu' | sudo -S -E shutdown -P now"
    }
  ],
  "provisioners": [
    {
      "type": "shell",
      "inline": ["sync"]
    }
  ]
}