Creating Windows virtual machines in OpenNebula is straightforward when using the right templates and guidance, allowing for repeatable, fully automated deployments. In this demonstration, we show how to build a Windows “golden image” that can be reused to instantiate multiple VMs efficiently—ensuring consistent configuration, optimal performance, and seamless integration with OpenNebula services.

Instead of distributing pre-installed Windows images, which isn’t allowed, we combine official Microsoft installation media with VirtIO drivers and OpenNebula contextualization packages to create a fully functional Windows VM template. This template, available on the OpenNebula Public Marketplace, simplifies multi-VM deployments and ensures that every VM starts with the same optimized settings.

Key Workflow

• Import the Windows VM Template: OpenNebula provides a ready-to-use Windows template that includes the required disks and a set of pre-configured optimization settings based on our Windows best-practice guidelines.
• Instantiate the VM: Attach the Windows installation ISO, configure the amount of CPU, memory, and storage resources, and start the OS installation.
• Apply VirtIO drivers and contextualization: Ensure optimal VM performance and automated OpenNebula integration (network, hostname, user credentials, disk resizing, and custom boot actions).
• Save the golden image: Preserve the configured VM disk to instantiate additional VMs with the same settings.
• Deploy multiple VMs: Instantiate several VMs from the saved image with a few clicks, fully configured and ready for use.

Key Benefits

• Pre-optimized for Windows—The template includes all required drivers, contextualization tools, and best-practice settings, eliminating the need to assemble and fine-tune these components manually.
• Consistent configuration—Every VM includes the same drivers, OS settings, and contextualization.
• Seamless OpenNebula integration—Networking, credentials, and system settings are applied automatically.
• Flexible reuse—The golden image can be used across different datastores and clusters.

This screencast walks you through the entire process—from importing the template to deploying multiple VMs—allowing you to see the workflow in action and understand how the provided template simplifies Windows VM image preparation and deployments.

Watch the Full Demo

More screencasts are available here.

By leveraging OpenNebula’s templates, automation, and contextualization, organizations can streamline Windows VM management, achieve consistent performance, and scale deployments with minimal effort. In case of necessity to deal with Windows image preparation and upgrades on a regular basis we encourage you to use the one-apps tool, which is used by the OpenNebula team for preparing all appliances supplied via our Marketplaces.