Virtual Disk (VMDK) cloning operations use VAAI (vStorage APIs for Array Integration) to offload the cloning process to the underlying storage array, resulting in faster and more efficient cloning. The process of cloning multiple VMs via PowerShell and VAAI involves creating new VMs by cloning from existing ones using the New-VM cmdlet while leveraging VAAI for optimized performance. Below is an example PowerShell script to perform clone operations of multiple VMs using VAAI:

# Define the source VM template to clone from
$sourceVMName = "SourceVM_Template"
$sourceVM = Get-VM -Name $sourceVMName

# Define the number of VM clones to create
$numberOfClones = 5

# Specify the destination folder for the cloned VMs
$destinationFolder = "Cloned VMs"

# Loop to create the specified number of clones
for ($i = 1; $i -le $numberOfClones; $i++) {
    # Define the name of the new clone VM
    $cloneName = "Clone_VM_$i"

    # Clone the VM using VAAI for optimized performance
    New-VM -VM $sourceVM -Name $cloneName -Location $destinationFolder -RunAsync -UseVAAI
}

# Wait for all the clone operations to complete
Get-Task | Where-Object {$_.Description -match "Create VM from existing VM" -and $_.State -eq "Running"} | Wait-Task

Explanation:

1. The script starts by defining the name of the source VM template to clone from using the $sourceVMName variable.
2. The $sourceVM variable is used to retrieve the actual VM object corresponding to the source VM template.
3. The $numberOfClones variable specifies the number of VM clones to create. You can modify this value according to your requirement.
4. The $destinationFolder variable specifies the folder where the cloned VMs will be placed. Ensure that this folder exists in the vSphere inventory.
5. A loop is used to create the specified number of clones. The loop iterates $numberOfClones times, and for each iteration, a new clone VM is created.
6. The name of each clone VM is constructed using the $cloneName variable, appending a unique number to the base name “Clone_VM_” (e.g., Clone_VM_1, Clone_VM_2, etc.).
7. The New-VM cmdlet is used to clone the source VM template and create a new VM with the specified name. The -UseVAAI parameter enables VAAI offloading for optimized performance during the cloning process.
8. The -RunAsync parameter allows the clone operation to run asynchronously, so the script doesn’t wait for each clone operation to complete before moving to the next iteration.
9. After all the clone operations are initiated, the script waits for all the clone tasks to complete using the Get-Task and Wait-Task cmdlets. The Wait-Task cmdlet ensures that the script doesn’t proceed until all the clone operations are finished.

Please note that the UseVAAI parameter is only supported if the underlying storage array and storage hardware are VAAI-compatible. If your storage array doesn’t support VAAI, the -UseVAAI parameter will have no effect, and the cloning process will use traditional methods.

Always test any scripts or commands in a non-production environment before running them in a production environment. Ensure that you have appropriate permissions and understand the impact of the operations before executing the script.