Over time, QCOW2 files grow as Windows writes temporary files, logs, and system updates. Even if you delete these files inside Windows, the host-level .qcow2 file remains bloated.
# Power down the VM safely prior to maintenance qemu-img convert -O qcow2 -c win10.qcow2 compressed_win10.qcow2 Use code with caution. windows 10qcow2
A file is a virtual disk image format for QEMU. Unlike raw images that take up their full allocated space immediately, qcow2 files are "thin-provisioned." Over time, QCOW2 files grow as Windows writes
Creating your own takes 30-45 minutes of clicking. For automation or testing, pre-made images are available. Warning: Only download from trusted sources to avoid malware. A file is a virtual disk image format for QEMU
You can create a "base" Windows 10 qcow2 image (fully activated and updated) and then create dozens of "overlay" images for individual users or tests. Each overlay is just a few MB initially and only stores differences. This is a game-changer for labs.