- `iso_checksum` (string) - The checksum for the ISO file or virtual hard drive file. The algorithm to use when computing the checksum can be optionally specified with `iso_checksum_type`. When `iso_checksum_type` is not set packer will guess the checksumming type based on `iso_checksum` length. `iso_checksum` can be also be a file or an URL, in which case `iso_checksum_type` must be set to `file`; the go-getter will download it and use the first hash found. - `iso_url` (string) - A URL to the ISO containing the installation image or virtual hard drive (VHD or VHDX) file to clone.