Use code with caution.
Launch a terminal and run:
qemu-img convert -O qcow2 -c win10.qcow2 win10_compressed.qcow2 Use code with caution. Creating Linked Clones (Master Template)
To tailor this guide for your specific infrastructure, let me know:
You will boot from the ISO and install onto the qcow2 disk.
The qemu-img command can convert between almost any format:
Developers can isolate testing environments. By utilizing QCOW2 snapshots, you can test registry modifications, malware behavior, or software deployments on Windows 10 without risking your host system. 2. Legacy Application Support
qemu-img convert -f vhdx -O qcow2 windows10.vhdx windows10.qcow2
With your disk image created and prerequisites in place, you can now start the VM and install Windows. You can use virt-manager for a graphical experience or use the command line for more control.
The first step is to create an empty file that will serve as your VM's hard drive. Use the qemu-img command-line tool, which you installed with the QEMU package.
Don't just clone a raw install. Before you convert your Windows 10 VM to a reusable qcow2 image, make sure to run Sysprep ! This strips out the specific machine IDs, ensuring every clone gets a fresh, unique system SID.
With QCOW2, you can take a snapshot of your Windows 10 VM while it is running . Imagine installing suspicious software or testing a beta driver. If something breaks, you roll back to the snapshot in seconds. This is native to QCOW2, unlike raw .img files.
2026-04-18 Subject: Performance, compatibility, and best practices for Windows 10 on QCOW2 images.
: Download the official ISO from the Microsoft Evaluation Center or via the Media Creation Tool.
You forgot VirtIO drivers. Check Device Manager → Storage controllers. If you see "Standard SATA AHCI Controller", you are not using VirtIO. Reinstall virtio-win-guest-tools .
Open PowerShell as an Administrator and execute the following to disable background search indexing and disk defragmentation (which degrades host performance when mapped to thin-provisioned QCOW2 storage): powershell
qemu-img create -f qcow2 windows10.qcow2 80G