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14.7. Creating and Formatting New Images or Devices

Create the new disk image filename of size size and format format.
# qemu-img create [-f format] [-o options] filename [size]
If a base image is specified with -o backing_file=filename, the image will only record differences between itself and the base image. The backing file will not be modified unless you use the commit command. No size needs to be specified in this case.