Get VM Generation ID from powershell

[sjesse]

I need to monitor a vm for id changes that can break a license server for a software call tableau we use. I am already checking the uuid and mac address, but they say they also look at the VM-generation id,in the vmx file its vm.genid I believe

does anyone know what property this is.

[LucD]

Try with

Get-AdvancedSetting -Entity $vm -Name 'vm.genid'

Get-AdvancedSetting -Entity $vm -Name 'vm.genidx'

[sjesse]

Thanks, I forgot about that one. Do you think there is anyway to improve this? So far it works and it pretty quick I'm going to try and find ways to change these manually. I'm planning on adding custom monitor to the vms that use licensing based on this.

$vmname="name of vm"

$olduuid=""

$oldmacs=""

$olddiskuuid=""

$oldvmgenid=""

$oldvmgenidx=""

if((Test-Path C:\users\sjesse\$vmname-uuid.xml))

{

    $olduuid=Import-Clixml C:\users\sjesse\$vmname-uuid.xml

    $oldmacs=Import-Clixml C:\users\sjesse\$vmname-macs.xml

    $olddiskuuid=Import-Clixml C:\users\sjesse\$vmname-diskuuid.xml

    $oldvmgenid=Import-Clixml C:\users\sjesse\$vmname-genid.xml

    $oldvmgenidx=Import-Clixml C:\users\sjesse\$vmname-genidx.xml

}

#get vm uuid

$vm=get-vm $vmname| get-view | select @{l="uuid";e={$_.config.instanceuuid}}

$uuid=$vm.uuid

#get vm mac addresses

$macaddress= get-vm $vmname | Get-NetworkAdapter | select -ExpandProperty MacAddress

#get vm disk uuids

$diskuuid= get-vm $vmname | Get-HardDisk |

Select @{N='VM';E={$_.Parent.Name}},

    @{N='Harddisk';E={$_.Name}},

    @{N='Uuid';E={$_.ExtensionData.Backing.Uuid}}

#get vm gen ids

$vmgenid=Get-AdvancedSetting -Entity $vmname -Name "Vm.genid"

$vmgenidx=Get-AdvancedSetting -Entity $vmname -Name "Vm.genidx"

if($olduuid -ne $uuid)

{

    Write-Host $vmname "uuid changed from $olduuid to $uuid"

    $olduuid

    $uuid

}

if(@(Compare-Object $macaddress $oldmacs -SyncWindow 0).Length -ne 0)

{

    Write-Host $vmname "a mac address changed"

}

if(@(Compare-Object $diskuuid $olddiskuuid -SyncWindow 0).Length -ne 0)

{

    Write-Host $vmname "a disk uuid changed"

}

if(@(Compare-Object $vmgenid.Value $oldvmgenid.Value -SyncWindow 0).Length -ne 0)

{

    Write-Host $vmname "Generiation ID changed"

}

if(@(Compare-Object $vmgenidx.Value $oldvmgenidx.Value -SyncWindow 0).Length -ne 0)

{

    Write-Host $vmname "Generiation ID changed"

}

$uuid | Export-Clixml C:\users\sjesse\$vmname-uuid.xml

$macaddress | Export-Clixml C:\users\sjesse\$vmname-macs.xml

$diskuuid | Export-Clixml C:\users\sjesse\$vmname-diskuuid.xml

$vmgenid | Export-Clixml C:\users\sjesse\$vmname-genid.xml

$vmgenidx | Export-Clixml C:\users\sjesse\$vmname-genidx.xml

[LucD]

I would do something like this.

Less code and easier to add/remove entries to be checked.

$vmname="MyVM"

$fileName = "C:\Temp\$($vm.Name)-id.xml"

$vm = Get-VM -Name $vmname

$tab = @{

   uuid = $vm.ExtensionData.Config.InstanceUuid

   mac = (Get-NetworkAdapter -VM $vm).MacAddress

   diskuuid = (Get-HardDisk -VM $vm).ExtensionData.Backing.Uuid

   genid = (Get-AdvancedSetting -Entity $vm -Name "Vm.genid").Value

   genidx = (Get-AdvancedSetting -Entity $vm -Name "Vm.genidx").Value

}

if((Test-Path -Path $fileName))

{

   $tabOld = Import-Clixml -Path $fileName

 

   $tab.GetEnumerator() |

   ForEach-Object -Process {

   if($tab."$($_.Name)" -ne $tabOld."$($_.Name)"){

   Write-Host "$($vm.Name) $($_.Name) changed"

   }

   }

}

$tab | Export-Clixml -Path $fileName

[sjesse]

Thanks, that's fantasic, less code is better :smileyhappy:. That will probably work out better for the monitors I need to make.

[LucD]

I do have one worry though, what if the VM has more than 1 harddisk or 1 vNIC?

[sjesse]

Thats the purpose  of the Export-Clixml command.it the xml file it makes looks like this

<Objs Version="1.1.0.1" xmlns="http://schemas.microsoft.com/powershell/2004/04">

  <Obj RefId="0">

    <TN RefId="0">

      <T>Selected.VMware.VimAutomation.ViCore.Impl.V1.VirtualDevice.FlatHardDiskImpl</T>

      <T>System.Management.Automation.PSCustomObject</T>

      <T>System.Object</T>

    </TN>

    <MS>

      <S N="VM">vm</S>

      <S N="Harddisk">Hard disk 1</S>

      <S N="Uuid">6000C291-e845-56f8-59be-b8d7006053fe</S>

    </MS>

  </Obj>

  <Obj RefId="1">

    <TNRef RefId="0" />

    <MS>

      <S N="VM">vm</S>

      <S N="Harddisk">Hard disk 2</S>

      <S N="Uuid">6000C296-de3a-38db-65a7-7fa89d4f58cc</S>

    </MS>

  </Obj>

</Objs>

its also why the compare-object  was needed because these reimport as arrays. If the compare-object result is more then 0 there is a difference bteween the two.

[LucD]

Than you probably have to change my comparison.

[sjesse]

Yeah, I didn't get any errors, but the comparison always failed. I read thats because -ne and -eq compares the 1st row of the array against the complete other array. I changed

  

          if($tab."$($_.Name)" -ne $tabOld."$($_.Name)"){

to

   if(@(Compare-Object $tab."$($_.Name)" $tabOld."$($_.Name)" -SyncWindow 0).Length -ne 0){

its working as expected.

[LucD]

Great.