Some useful command to help running and setup qemu…

• Create an empty compressed 10 Go disk image (in qcow2 format):

  $ qemu-img create -f qcow2 /home/kevin/qemu-disk-image.qcow 10G

• Boot on your machine’s CD-Rom in qemu with previous disk image as primary HDD:

  $ qemu -cdrom /dev/cdrom -hda /home/kevin/qemu-disk-image.qcow -boot d

• Same as above but with a CD-Rom iso image:

  $ qemu -cdrom /home/kevin/ubuntu.iso -hda /home/kevin/qemu-disk-image.qcow -boot d

• Boot the previously created disk image:

  $ qemu /home/kevin/qemu-disk-image.qcow

• Convert qcow image to a raw image:

  $ qemu-img convert /home/kevin/qemu-disk-image.qcow -O raw /home/kevin/qemu-disk-image.raw

• Convert raw image to a qcow image:

  $ qemu-img convert -f raw qemu-disk-image.raw -O qcow2 qemu-disk-image.qcow

• Mount a RAW disk image:

  $ mount -o loop,offset=32256 /home/kevin/qemu-disk-image.raw /media/qemu/

• Mount a qcow2 disk image via the nbd protocol (don’t forget to install the nbd-client package):

  $ modprobe nbd max_part=63
  $ qemu-nbd -c /dev/nbd0 /home/kevin/qemu-disk-image.qcow2
  $ mount /dev/nbd0p1 /media/qemu

• To run a x86_64 guest system on a 32-bit host, simply use qemu-system-x86_64 binary command instead of qemu.