Can I backup VMs on ESXi Free with UB?
Yes, you can deploy the UB free edition to VMware’s free ESXi environment. Please note that you will have to install the Unitrends agent on all VMs that you intend to backup. Host-level snapshot backups are NOT supported with free ESXi, so using the Unitrends agent is required. Connecting the VM's on the enterprisie ESXi host to do agentless backups requires multiple socket support, which is not included in the free license.
How do I restore a VM using
You can restore a VM using Unitrends Windows Integrated Recovery ISO, after creating a VM with similar resources as the original VM (boot from the ISO to load the data from the Unitrends).
For more information on Unitrends supported ESXi, see Virtualization Protector requirements in the Unitrends Administrator's Guide.
For more information on VMware licensing, check out this webiste: http://www.vmware.com/products/datacenter-virtualization/vsphere/compare-editions.html