Andrew Mercer
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Import and convert KVM images

Part of the KVM overview. Convert raw, VDI and VMDK images to qcow2 and image a physical disk.

Convert between formats

qemu-img convert -f raw -O qcow2 disk.img disk.qcow2
qemu-img convert -c -f raw -O qcow2 disk.img disk.qcow2         # -c compresses
qemu-img convert -p -f vdi -O qcow2 disk.vdi disk.qcow2         # VirtualBox: qemu-img reads VDI directly
qemu-img convert -p -f vmdk -O qcow2 disk.vmdk disk.qcow2       # VMware

qemu-img info disk.img before and after shows the virtual size and actual disk usage (an 8 GiB raw image that is mostly empty often converts to about 1 GiB).

Image a physical disk

sudo dd if=/dev/sda of=/mnt/external/sda.img bs=4M status=progress
qemu-img convert -p -f raw -O qcow2 /mnt/external/sda.img sda.qcow2