Clarify host requirements and Windows support as host

[mloskot]

Having just learned about KubeVirt and spent some time browsing through the documentation as well as the issues on GitHub, I have failed to find answer to the basic questions:

1. What are the host requirements?
2. Can I run KubeVirt on Windows host?

For example, if I run hybrid OS cluster on Windows host according to sig-windows-dev-tools and have control plane on Linux VM as master node and one or more Windows worker nodes, can I run KubeVirt on Windows host and deploy (nested?) Windows VM-s on such cluster? Is there any Hyper-V support?

Neither the front page, nor the quick starts offer the answer.
In fact, even the installation is clear on the host requirements. It only says

A few requirements need to be met before you can begin:

• Kubernetes cluster or derivative (...)

but that is not a no-brainer clarification. A reader needs to assume that Kubernetes cluster == Linux host, but is such assumption correct?

[kubevirt-bot]

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[aburdenthehand]

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Thanks for raising this issue. You're right, it's not adequately covered. I suspect the installation doc was written prior to windows nodes being properly supported in k8s. This definitely needs an update.
I think you've figured this out already but no, you cannot run the VMs on a Windows node. You can have Windows nodes in your cluster, but KubeVirt needs an underlying linux node to run VMs. You can run Windows VMs on the linux nodes though. Baremetal heavily preferred. You can run on nested virt but unless the nodes are optimized for it the VMs will suffer a performance hit - to what level is dependent on how the node is configured and what the workload is.

[kubevirt-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

/lifecycle stale

[kubevirt-bot]

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[aburdenthehand]

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