I encounter the same error again and figured out what the problem was! In my original problem report I specified "--size=100000000". Well that value is in _bytes_ so that is only 100M. So the image was filling up due to the kernel(large) and zlib(last alphabetically).
I filed a separate bug suggesting better documentation of the size option (#812727). It would have been nice if vmdebootstrap detected this problem and gave a more specific error. If it's too complicated to detect the image full issue, a sanity check on reasonable values of SIZE would have caught it too. Will change to wishlist. Thanks, -- Matt Taggart tagg...@debian.org