Sorry for starting with the probably most stupid Q. I have just entered the world of ESXi and I have installed the first ESXi and a couple of OS's, and it's all working fine.
But for saftey reason, I would like to backup and restore the different OS's, and maybe even the whole disk!
Q1. is that possible?
Q2. Is that possible with the free license or do I need full license to performe at least the first task (backup/restore an OS), or both (backup/restore the whole disk)?
Yes possible but in free license.If you are looking for production vms backup you need to buy backup software license with appropriate vendor.
Q2: No. All 3rd. Party Backup vendors use the vSphere API for Data Protection in combination with other remote / automatizations functions and these APIs are locked when using the Free ESXi Hypervisor. In the past only a few vendors exists (Trilead) which worked around. Years ago there was also GhettoVCB2 (community script) around but to be honest..... at the end you need a reliable Backup solution and all of them require a licensed ESXi with all open APIs. Yes... free/cheap Backup products exists like Veeam B&R Community version for up to 10 VMs. Nakivo have something similar.
Ways to get a licenced ESXi
1. VMUG Adv. (200?)
2. vSphere Essentials (470,- plus 62,-)