While nesting a VMware ESXi hypervisor inside another VMware product like Workstation, Fusion, or vSphere may be possible, doing so in a production environment probably isn't the best solution (that's me trying not to use the word "crazy"), and it definitely shouldn't be considered a supported architecture for an organization.
But the lack of official support from VMware has never slowed down the exploratory minds of the VMware community. These individuals work together to make the impossible possible, and they're always looking for the next thing to make virtualization life easier and more productive.
What exactly do we mean when we talk about "nesting"?
Basically, it means VMware vSphere can be virtualized within itself. In other words, you can install and operate the VMware ESXi hypervisor within a virtual machine running inside another hypervisor environment such as VMware vSphere.
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