If the Hyper-V role is not enabled for selected Windows Server hosts, Virtual Machine Manager will attempt to enable it automatically. ...

If the Hyper-V role is not enabled for selected Windows Server hosts, Virtual Machine Manager will attempt to enable it automatically. Enabling the Hyper-V role will cause the selected servers to immediately restart. Restarting the VMM management server will stop any running jobs and require the host to be added again after Hyper-V is enabled.

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