Hello.
If you require HA (high availability), you need vcenter server (this product requires own license) and at least one other ESXi host.
If your ESXi host uses a Free license you will need to purchase a paid license.
As you only have 3 VMs on your single ESXi host, I understand that your environment is small, your alternatives would be to purchase VMware vSphere kits:
If you only grow to a maximum of 3 ESXi hosts.
vmware vsphere essentials plus Kit (includes licenses for one vcenter server essentials and 3 ESXi hosts essentials (2 CPUs each)).
If you plan to start with 2 or 3 hosts and then keep on growing
vmware vsphere standard acceleration Kit (includes licenses for one vcenter server standard and 3 ESXi hosts standard (2 CPU each))
Enrique Espinel
Senior Technical Support on IBM, Lenovo, Veeam Backup and VMware vSphere.
VSP-SV, VTSP-SV, VTSP-HCI, VTSP
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