Windows Xpqcow2 -

For the uninitiated, Qcow2 is the disk format used by QEMU and many virtualization platforms (Proxmox, virt-manager). It stands for QEMU Copy-On-Write version 2. Unlike a raw disk image, Qcow2 is:

Inside the XP VM, zero out free space (e.g., using sdelete -z), then:

qemu-img convert -O qcow2 windows-xp.qcow2 windows-xp-shrunk.qcow2

QCOW2 stands for QEMU Copy On Write version 2. It is the primary disk image format used by the QEMU (Quick Emulator) virtualization solution. windows xpqcow2

While most users are familiar with formats like VMDK (VMware) or VDI (VirtualBox), QCOW2 offers distinct advantages, particularly when dealing with older operating systems like Windows XP.

Windows XP requires older hardware emulation to install correctly (specifically the IDE controller for the hard drive and a specific audio driver). Use the following command to start the installation: For the uninitiated, Qcow2 is the disk format

qemu-system-x86_64 \
  -m 1024 \
  -smp 2 \
  -drive file=windows-xp.qcow2,format=qcow2,if=ide \
  -cdrom /path/to/windows_xp.iso \
  -boot d \
  -device rtl8139,netdev=net0 \
  -netdev user,id=net0 \
  -device AC97 \
  -vga std

Last week, I needed to run an old Delphi 7 project (only works on XP). Instead of digging out a dusty ThinkPad, I:

All while the “image” sat on my NVMe drive, taking just 1.8 GB on disk. QCOW2 stands for QEMU Copy On Write version 2

| Feature | Benefit for Windows XP VM | |--------|---------------------------| | Snapshots | Save state before installing legacy software or testing patches | | Thin provisioning | Image grows only as data is written – saves disk space | | Compression | Reduce storage footprint (qcow2 can be compressed) | | Backing files | Create multiple derivative VMs from a base XP install | | Performance | Good balance of features vs speed on modern SSDs |

If using virt-manager, ensure the disk section uses:

<disk type='file' device='disk'>
  <driver name='qemu' type='qcow2' cache='writeback' io='native'/>
  <source file='/var/lib/libvirt/images/winxp.qcow2'/>
  <target dev='hda' bus='ide'/>
</disk>

Use bus='sata' or virtio if you pre-load XP with drivers.