enhancementhelp wanted
説明
Legacy operating systems like MS-DOS did not have official CD-ROM installation media (ISO) available, but rather floppy disks (IMG). For these older guests, it would be helpful for Packer to offer floppy-based builders (e.g. virtualbox-img rather than virtualbox-iso), so that these guests can be built directly from historical IMG files.
As a workaround, users can instruct Packer to boot an Ubuntu Live CD or similar, and use boot_command to launch a terminal, whereupon dd, shutdown -r, etc. can manipulate a floppy-based guest. It's not pretty.