Get-VMHostMetrics.ps1

<#
.SYNOPSIS
Collect configuration metrics for a VMHost, Cluster, Datacenter, or vCenter. For each VM Host found, these metrics are collected:
-Parent object(Cluster, Datacenter)
-Hardware model
-ESXi build 
-IP address 
-VMs on host
-physical CPUs(pCPU) on host
-virtual CPUs(vCPU) allocated
-vCPU to pCPU ratio

.DESCRIPTION
Connect to vCenter with Connect-VIServer before using this script.
Written with PowerShell v3.0 and PowerCLI 6.0(2548067).

.EXAMPLE
.\Get-VMHostMetrics -cluster "mycluster"
#>

[cmdletbinding()]
Param (
    [Parameter(ParameterSetName="VMHost",Mandatory=$true,Position=0)]
    [string]$vmhost,
    [Parameter(ParameterSetName="Cluster",Mandatory=$true)]
    [string]$cluster,
    [Parameter(ParameterSetName="Datacenter",Mandatory=$true)]
    [string]$datacenter,
    [Parameter(ParameterSetName="vCenter",Mandatory=$true)]
    [switch]$vcenter,
    [switch]$report = $true,
    [string]$reportName = "$($PSScriptRoot)\Reports\VMHostMetrics_"
)

function GetHostMetrics($h) {
    #Determine configuration metrics
    $view = $h | Get-View
    $vms = $h | Get-VM
    $totalCPU = ( $vms | Measure-Object -Sum -Property NumCPU).Sum
    if(!$totalCPU) { $totalCPU = 0 }
    $ratio = "{0:N3}" -f ($totalCPU/$h.NumCPU)

    #Create an ordered PS Custom Object and store the metrics
    $results = [pscustomobject][ordered]@{
        VMHost = [string]$h.name
        Parent = [string]$h.Parent
        Model = [string]$h.Model
        Build = [int]$view.Config.Product.Build
        IPAddress = ($h | Get-VMHostNetwork).VirtualNic | Where-Object{$_.ManagementTrafficEnabled} | Select-Object -ExpandProperty IP
        VMs = [int]$vms.count
        pCPU = [int]$h.NumCPU
        vCPU = [int]$totalCPU
        Ratio = [double]$ratio
    }
    return $results
}

#Switch the Parameter Set and collect the appropriate VMware object
$all = @()
try {
    switch($PSCmdlet.ParameterSetName) {
        "VMHost" {
            #Collect metrics from one host and append to $all
            $h = Get-VMHost $vmhost -ErrorAction Stop; $all += GetHostMetrics $h
            $reportName += $vmhost
            }
        "Cluster" { 
            #Loop through each host in the cluster, collect metrics, append to $all
            $h = Get-Cluster $cluster -ErrorAction Stop | Get-VMHost | sort Name
            $reportName += $cluster
            foreach($_h in $h) { Write-Host "$cluster - $_h - Collecting data"; $all += GetHostMetrics $_h  }     
            }
        "Datacenter" {
            #Loop thrugh each host in the datacenter, collect metrics, append to $all
            $h = Get-Datacenter $datacenter -ErrorAction Stop | Get-VMHost | sort Name
            $reportName += $datacenter
            foreach($_h in $h) { Write-Host "$datacenter - $_h - Collecting data"; $all += GetHostMetrics $_h  }
        }
        "vCenter" {
            #Loop all hosts in vCenter, collect metrics, append to $all
            $h = Get-VMHost -ErrorAction Stop | Sort Name 
            $reportName += "vCenter"
            foreach($_h in $h) { Write-Host "$_h - Collecting data"; $all += GetHostMetrics $_h }      
        }
    }
}
catch { Write-Host -ForegroundColor Red $_.Exception.Message; Exit }

$all | sort VMHost

#Export report
if($report -eq $true) {
    $reportName += "_$(Get-Date -Format yyyyMMdd_HHmmss).csv"
    $all | Export-csv $reportName -notype
    Write-Host "Metrics have been written to $reportName"
}