PowerCLI Set ESXi NTP Source - ESXi 6.7u3 and 7.0u3

.SYNOPSIS
Set NTP Source Servers for VMware ESXi
.DESCRIPTION
Example is using Google NTP source IP. This is not for production use.
.EXAMPLE
Set-EsxiNtpSource -vcenter 'vcenter.fqdn.com'
Set-EsxiNtpSource -vcenter 'vcenter.fqdn.com' -ntpSource "8.8.8.8"

Parameters:
$vcenter (vCenter FQDN)
$ntpSource (can be DNS or IPs)