Boot physical disk

In some cases, you may have a physical disk with Windows installed that you want to boot from in a virtual machine. This can be useful for testing or running legacy applications.

Before starting: Understand the formats

Before proceeding, it's important to understand the different disk image formats and how they relate to physical disks:

• RAW format
• QCOW2 format
• VMDK format

RAW is a raw disk image format that represents the exact contents of a disk. QCOW2 is a more advanced format that supports features like snapshots and compression. VMDK is a format used by VMware products.

When you have a physical disk, you can treat the entire disk, for example /dev/sdX, as a raw disk image. You can also create virtual disk images in QCOW2 or VMDK formats from the physical disk.

QCOW2 and VMDK formats are often used for virtual machines, while RAW is a simple representation of the disk contents.

QCOW2 supports features like snapshots and compression, making it more efficient for storage.

Similarly, VMDK is used by VMware products and can be converted to and from other formats.

Copy\Backup\Restore physical disk with virtual disk

To copy the physical disk to a virtual disk, you can use the dd command. This command will create an image of the physical disk and save it as a virtual disk file.

sudo dd if=/dev/sdX of=/path/to/virtual-disk.img bs=4M status=progress

Replace /dev/sdX with the actual device name of your physical disk and /path/to/virtual-disk.img with the desired path for the virtual disk image.

And of course, you can copy the virtual disk back to the physical disk if needed:

sudo dd if=/path/to/virtual-disk.img of=/dev/sdX bs=4M status=progress

This is useful if you want to back up the virtual disk or restore it to the physical disk later.

Convert a disk to qemu-img format

To convert a disk image to the QEMU image format, you can use the qemu-img command. This is particularly useful if you need to use the disk with QEMU or KVM.

sudo apt update
sudo apt install qemu-utils

Then, you can convert the disk image:

qemu-img convert -f raw -O qcow2 /path/to/virtual-disk.img /path/to/virtual-disk.qcow2

Or you can directly create a new qcow2 image from the physical disk:

qemu-img convert -f raw -O qcow2 /dev/sdX /path/to/virtual-disk.qcow2

On the other way, you can also burn a qcow2 image back to a physical disk:

qemu-img convert -f qcow2 -O raw /path/to/virtual-disk.qcow2 /dev/sdX

Convert a disk to\from VMDK format

To convert a disk image to or from VMDK format, you can also use the qemu-img command. This is useful if you need to work with VMware products.

qemu-img convert -f raw -O vmdk /path/to/virtual-disk.img /path/to/virtual-disk.vmdk

To convert a VMDK back to a raw disk image, you can use:

qemu-img convert -f vmdk -O raw /path/to/virtual-disk.vmdk /path/to/virtual-disk.img

And you can also convert a qcow2 image to VMDK format:

qemu-img convert -f qcow2 -O vmdk /path/to/virtual-disk.qcow2 /path/to/virtual-disk.vmdk

To convert a VMDK back to qcow2 format, you can use:

qemu-img convert -f vmdk -O qcow2 /path/to/virtual-disk.vmdk /path/to/virtual-disk.qcow2

Booting the virtual machine

It is suggested to use the gnome-boxes application to boot the virtual machine with the created disk image. This application provides a user-friendly interface for managing virtual machines.

To boot the virtual machine, follow these steps:

1. Convert the physical disk to a virtual disk image to qcow2 format using the qemu-img command as shown above.
2. Open gnome-boxes.
3. Click on "New" to create a new virtual machine.
4. Select "Use a disk image" and choose the qcow2 image you created.
5. Follow the prompts to configure the virtual machine settings.
6. Once the virtual machine is created, you can start it by clicking on the "Start" button.

If the virtual machine does not boot, you can enable the UEFI firmware in the virtual machine settings. This is often necessary for Windows installations.

<os firmware="efi">
    ...
</os>