Steps to reproduce:
If you have VMs with vSphere Fault Tolerance (FT), there is a primary and secondary VM which are using the same name in vSphere. But vmware.vm.discovery is not able to take this into account.

Result:
Zabbix tries to create two hosts with the same name, which fails on the second one.

Expected:
There should be a label macro that allow you to detect if it is a virtual machine with FT and if it is a primary or a secondary one. My alternative would be to write the *

* after the affected disovered host at the moment, which does not necessarily make it more readable.

As a small example, vSphere displays the VMs in the overview like this. If Zabbix would do the same for {*}

{}{*}, it would help a lot.