Prepare Windows Image & Deploy it on Cloud Server

You can deploy a cloud server from your own Windows image. This is useful when you need a preconfigured Windows environment with your own software, services, and system settings.

This guide covers how to prepare a Windows virtual machine (VM) image so it runs correctly in our OpenStack-based cloud, upload it to the Customer Portal, and deploy a cloud server from it.

Use this guide if:

You already have a Windows VM and need to prepare it for deployment
You need to create a new Windows VM from an installation ISO and prepare it for deployment

Prerequisites

Customer Portal account
Local machine (Windows, Linux, or macOS)
Installed virtualization software (we use QEMU in examples)
Windows installation ISO (required only if you are creating a new VM)

Image requirements

Ensure your Windows VM meets the following requirements:

Architecture: x64 OS
Boot firmware: Only BIOS (UEFI is not supported)
Windows 11 is not currently supported
Local virtual disk in qcow2 format (recommended)
DHCP enabled; no static network configuration
VirtIO drivers installed
Cloudbase-Init installed and configured
Image generalized using Sysprep

Prepare a Windows image

Create a VM and install Windows

Use this section only if you are creating a new VM. If you already have a configured Windows VM, skip ahead to Configure the Windows VM.

Install QEMU

QEMU is a free and open-source cross-platform virtualization environment.

Windows (PowerShell, run as administrator)

Enable Windows Hypervisor Platform:

Enable-WindowsOptionalFeature -FeatureName HypervisorPlatform -Online

Install QEMU:
```
winget install SoftwareFreedomConservancy.QEMU
```
Or use a ready-made installer for Windows.
Restart Windows.

Ubuntu/Linux

sudo apt-get install qemu-system

Fedora

sudo dnf install qemu qemu-kvm
# or
sudo dnf install @virtualization

Red Hat/CentOS

sudo yum install qemu qemu-kvm

SUSE

zypper install qemu

Arch Linux

sudo pacman -S qemu

macOS (Homebrew)

brew install qemu

macOS (MacPorts)

sudo port install qemu

Create a local virtual disk

When installing Windows from an ISO, you must first create a virtual disk to install Windows on. Choose a <disk-size> that fits your OS installation requirements (for example, 30G).

Creating a virtual disk does not mount it anywhere. You mount it to the VM later with the -drive file=… option.

Windows (from %ProgramFiles%\qemu)

.\qemu-img.exe create -f qcow2 C:\path-to\windows-virtual-disk.qcow2 <disk-size>

Linux / macOS

qemu-img create -f qcow2 windows-virtual-disk.qcow2 <disk-size>

Download VirtIO drivers

Windows does not detect VirtIO disks by default during installation, so you must load the driver manually from an ISO.

Download the prebuilt VirtIO drivers from the Fedora stable-virtio repository (for example, virtio-win.iso).

Launch the VM

Start the VM with your Windows installation ISO and the VirtIO driver ISO attached.

Use -m and -smp to set memory and vCPUs to match the configuration you plan to use on the cloud server.

Windows (PowerShell, run as administrator, from %ProgramFiles%\qemu)

.\qemu-system-x86_64.exe `
  -accel whpx `
  -m 4096 -smp 2 `
  -drive file=C:\path-to\windows-virtual-disk.qcow2,if=virtio,format=qcow2 `
  -drive file=C:\path-to-virtio-win.iso,media=cdrom `
  -cdrom C:\path-to-windowsOS.iso `
  -device virtio-net-pci,netdev=n1 `
  -netdev user,id=n1 `
  -boot order=d `
  -display default

Linux

qemu-system-x86_64 \
  -enable-kvm \
  -m 4096 -smp 2 \
  -drive file=windows-virtual-disk.qcow2,format=qcow2,if=virtio \
  -drive file=/path-to-virtio-win.iso,media=cdrom \
  -cdrom /path-to-windowsOS.iso \
  -device virtio-net-pci,netdev=n1 \
  -netdev user,id=n1 \
  -boot order=d \
  -display default

macOS

qemu-system-x86_64 \
  -accel tcg,thread=multi \
  -m 4096 -smp 2 \
  -drive file=windows-virtual-disk.qcow2,format=qcow2,if=virtio \
  -drive file=/path-to-virtio-win.iso,media=cdrom \
  -cdrom /path-to-windowsOS.iso \
  -device virtio-net-pci,netdev=n1 \
  -netdev user,id=n1 \
  -boot order=d \
  -display default

Install and configure Windows

Use this section only if you are preparing a new image from a Windows installation ISO. If you already have a preconfigured Windows system, skip ahead to Configure the Windows VM.

Start the installation. At the disk selection step, the list of available disks is empty.
Click Load driver.
Browse to the VirtIO ISO (for example, CD Drive (D:) virtio-win-0.1.285).
Browse to the VirtIO storage driver directory that matches your Windows version and architecture (for example, viostor\w10\amd64).
Select the detected VirtIO SCSI controller driver, then click Next.

You return to the disk selection screen. The disk is now available.
Continue the installation. Use the built-in Administrator account to ensure compatibility with Cloudbase-Init and standard Windows behavior.
After the reboot, wait for the installation to finish.
At the final installation step, click I don't have Internet. Networking is not available yet because the VirtIO network driver is not installed.
Click Continue with limited setup.

Configure the Windows VM

Install and configure any applications, services, and system settings required for your environment before preparing the image.

Install VirtIO drivers

Download the VirtIO drivers.
Open or mount the VirtIO driver ISO.
From the root of the ISO, run virtio-win-guest-tools.exe.
Verify that the network is available and that Device Manager shows no unknown devices.

Before creating an instance in the Customer Portal, choose the password authentication method. After the instance is created, a temporary auto-generated password is sent to the email addresses of account contacts with a Primary or Technical role.

Download the installer from cloudbase.it.
During installation, enable:
- Use metadata password
- Run Cloudbase-Init service as LocalSystem

Configure Cloudbase-Init

Cloudbase-Init retrieves instance metadata from OpenStack during the first boot and uses it to apply system and network configuration.

Open the configuration file:

%ProgramFiles%\Cloudbase Solutions\Cloudbase-Init\conf\cloudbase-init.conf

Add the following line at the end:

metadata_services=cloudbaseinit.metadata.services.configdrive.ConfigDriveService,cloudbaseinit.metadata.services.httpservice.HttpService

Validate configuration and clean up

Remove temporary files (for example, with the cleanmgr utility)
Ensure DHCP is enabled
Ensure no static IP configuration is present

Run Sysprep

Do not start the VM again after running Sysprep — doing so may corrupt the image.

Open PowerShell as an administrator, navigate to the Sysprep directory (%SystemRoot%\System32\Sysprep), and run:
```
.\sysprep.exe
```
Select:
- Enter System Out-of-Box Experience (OOBE)
- Generalize
- Shutdown

The VM powers off. The image is ready for upload.

OOBE is required for the deployment flow described in this guide. Fully unattended Windows deployments can use different Sysprep and Cloudbase-Init configurations and typically do not require enabling OOBE.

Uploading the image to the Customer Portal

Upload the qcow2 image and use it to deploy a cloud server. Because Windows images are typically large, use Option 2: Upload by cURL or Option 3: Via the OpenStack API instead of drag and drop (see How to upload your own image).

When you first connect to the provisioned cloud server, the Windows OOBE setup starts. Follow the on-screen prompts to finish the system initialization.

How to prepare your own OS image and deploy it on a cloud server (Linux, Unix, or BSD)

How to prepare your own Windows image and deploy it on a cloud server