Change UUID on VMs

[SENNAF1]

I have a issue with duplicate UUIDs  and was looking for a script to run on all the duplicates.  I found a blog post with a solution but am unable to get it to work.

https://www.derekseaman.com/2010/10/making-your-vmware-vm-uuids-unique.html 

The script works fine but errors out at $vm.Extensiondata.ReconfigVM_Task($spec) I can only figure this is because it is an old post and I am on 6.0.

Can someone help me get this to work?

Here is the error:

VM: EQRTEST03

New UUID: 4221873a-7f85-c9f3-ead5-214626065110

You cannot call a method on a null-valued expression.

At D:\IT Tools\VMWARE\vSphereScripts\Change UUID\CHANGE_UUID.ps1:13 char:1

+ $VM.Extensiondata.ReconfigVM_Task($spec)

+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException

    + FullyQualifiedErrorId : InvokeMethodOnNull

Here is the script:

# Usage: .changeUUID.ps1

if ($args[0].length -gt 0) {
connect-viserver $args[0]
$VMs = get-vm
foreach ($vm in $VMs){
$date = get-date -format “dd hh mm ss”
$newUuid = “56 4d 50 2e 9e df e5 e4-a7 f4 21 3b ” + $date
echo “VM: ” $VM.name “New UUID: ” $newuuid
$spec = New-Object VMware.Vim.VirtualMachineConfigSpec
$spec.uuid = $newUuid
$vm.Extensiondata.ReconfigVM_Task($spec)
start-sleep -s 2
}
}

[LucD]

That script seems to be running ok in vSphere 6 for me.

I suspect there might be an issue with that specific VM.

Does

Get-VM -Name EQRTEST03

return a valid VirtualMachine object?

[SENNAF1]

LucD thanks for the response,

I have been playing with this and I did the steps manually by typing each command.  It appears that my for each statement in the script is not passing the variable $VM for the Extensiondata.

PowerCLI C:\> $VM = Get-VM EQRTEST03
PowerCLI C:\> $VM

Name                 PowerState Num CPUs MemoryGB
----                 ---------- -------- --------
EQRTEST03            PoweredOn  2        4.000

PowerCLI C:\> $spec = New-Object VMware.Vim.VirtualMachineConfigSpec

PowerCLI C:\> $spec.uuid = '56 4d 50 2e 9e df e5 e4-a7 f4 21 3b aa 11 bb 22'
PowerCLI C:\> $vm.Extensiondata.ReconfigVM_Task($spec)

Type                                                                                      Value
----                                                                                      -----
Task                                                                                      task-731

Any ideas?

[SENNAF1]

I should also mention I modified the script to use Get-content and I only have the EQRTEST01 VM in the csv.  But if it works in my echo statement why does it not work in the next line?

$VMs = Get-content 'D:\VMlist.csv'

foreach ($VM in $VMs){

$date = get-date -format “dd hh mm ss”

$newUuid = “56 4d 50 2e 9e df e5 e4-a7 f4 21 3b” + $date

echo “VM: ” $VM “New UUID: ” $newuuid

$spec = New-Object VMware.Vim.VirtualMachineConfigSpec

$spec.uuid = $newUuid

echo “VM: ” $VM

$VM.Extensiondata.ReconfigVM_Task($spec)

start-sleep -s 2

[LucD · Accepted solution]

Try changing that first line into

$VMs = Get-VM -Name (Get-content 'D:\VMlist.csv')

[SENNAF1]

That was it, can you explain what the () do?

[LucD]

They set the evaluation order, first the expression between () will be executed.

So this Import-Csv will read all the VMnames from the CSV.

The result will be an array of strings.

This array of strings is passed on the Name parameter of the Get-VM cmdlet.

And that returns all the VirtualMachine objects corresponding with the names in the CSV