# List Memory Allocated out of total Physical Memory
# http://www.a2-alpha.co.uk
# 20100520

#Check for VMware PS Snapin - load and initialise if not

$erroractionpreference = "silentlycontinue"

$snapins = get-pssnapin | select Name
foreach($snapin in $snapins)
{
        if($snapin.Name -eq "VMware.VimAutomation.Core"){
        $result = "Yes"
    }
    else
    {
        $result = "No"
    }
}
if($result -eq "No")
{
    Add-PSsnapin VMware.VimAutomation.Core
    Initialize-VIToolkitEnvironment.ps1
}

#Test if connected to viserver or not

$Error.clear()

get-vm | out-null

$E = $Error
$E = $E | out-string
if($E.Contains("Get-VM"))
{
    $vcserver = read-host "Enter vCenter name or ESX host name"
    $us = read-host "Enter Username"
    $pw = read-host "Enter Password" -assecurestring:$true
    $cred = New-Object System.Management.Automation.PSCredential -ArgumentList $us,$pw
    Connect-VIServer -Server $vcserver -Credential $cred | out-null
    [int]$connectionstate = 0
}

#Clear Screen ready for results

clear
" "
"** Memory Allocation and Memory Allocated to Physical Memory Available **"
" "

#Get all powered on VMs and get memory

$clusters = get-cluster | sort Name
foreach($cluster in $clusters)
{
"Cluster: $cluster"
" "
$vmon = get-vm -location $cluster | where {$_.PowerState -eq "PoweredOn"}
$vmoncount = $vmon.Count
$vmonmems = get-vm -location $cluster | where {$_.PowerState -eq "PoweredOn"} | select Name, MemoryMB
$memtotal = 0

#Run through each VM and count memory

foreach($vmonmem in $vmonmems)
{
      [int]$number = $vmonmem.MemoryMB
      $memtotal += $number
}
"$memtotal MB`t Total Memory assigned across all hosts"

#Get hosts then run through each to count total memory

$vmhosts = get-vmhost -location $cluster | get-view | sort Name
$memorytotal = 0
foreach($vmhost in $vmhosts)
{
      [int]$physmem = (($vmhost.Hardware.MemorySize)/1024/1024)
      $memorytotal += $physmem
}
"$memorytotal MB`t Total Physical memory available across all hosts"
$percallocated = [math]::round((([int]($memtotal)/[int]($memorytotal))*100),0)
"$percallocated % `t `t Memory allocated from total available"
" "
if($percallocated -gt [int](100))
{
    "The memory in this environment is Over Commited"
}

#Create table for memory allocation information within each host

$Report = @()
ForEach($vmhost in $vmhosts)
{
      $vmsrunningperhost = (Get-vmhost $VMHost.name | get-vm | where {$_.Powerstate -eq "PoweredON"})
      $runningperhostcount = (Get-vmhost $vmhost.name | get-vm | where {$_.Powerstate -eq "PoweredON"} | Measure-Object).Count
      $number = 0
      $memtotal = 0
      foreach($vm in $vmsrunningperhost)
      {
              [int]$number = $vm.MemoryMB
              $memtotal += $number
      }
      [int]$memtotal = $memtotal/1024
      $memorytotal = [math]::round(((($vmhost.Hardware.MemorySize)/1024/1024/1024)),0)
      $vmem2pmem = [math]::round((([int]($memtotal)/[int]($memorytotal))*100),1)

      $ReportObj = "" | Select "ESX Host", "Physical Memory Total", "Memory Allocated", "Allocated (%)", "Number of Running VMs" 
      $ReportObj."ESX Host" = $vmhost.Name
      $ReportObj."Physical Memory Total" = $memorytotal
      $ReportObj."Memory Allocated" = $memtotal
      $ReportObj."Allocated (%)" = $vmem2pmem
      $ReportObj."Number of Running VMs" = $runningperhostcount
      $Report += $ReportObj
}
$Report | format-table
}
#Disconnect after results displayed if it was not connected when script was run

if($connectionstate -eq 0)
{
     disconnect-viserver -confirm:$false
}