Che tipo di licenza hai?
Probably you have free standalone hypervisor. The problem is that for free ESXI, VMware does not provide full support of VMware vSphere Storage APIs – Data Protection (formerly known as VMware vStorage APIs for Data Protection or VADP).
You need of one license vSphere to unlock API. The least expensive option is an "Essentials Kit".
Other alternative is Ghetto VCB.
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la licenza che ho è:
VMware vSphere 6 Hypervisor
non credo si tratta di una free, o sbaglio ?
For a single/standalone hypervisor there's always a free license. You have the option to schedule VCB script as suggested above.