vmdb2 cannot currently build an image without partitions. Such an image would sometimes be nice, and it’d be easier to resize. The reason partitions are required is that vmdb2 specification files refer to devices by symbolic names, or tags, and there’s no way to refer to the whole image with a tag.

This will eventually be rectified. See https://gitlab.com/larswirzenius/vmdb2/-/issues/21 if you want to comment.