Free ESXi or paid for licensed ESXi? It matters:
https://forums.veeam.com/vmware-vsphere-f24/can-you-backup-vms-on-esxi-7-free-license-using-vbr-comm...This article says you need root privileges for ESXi with no vCenter Server:
https://helpcenter.veeam.com/docs/backup/permissions/installation.html?ver=120
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