# takeVmSnapshot.ps1

$vmNames='Test-VM1','Cowabunga-VM4'
$snapShotLabel="Snapshot $(get-date -Format yyyyMMddTHHmmss)"

function takeVmSnapshot([string[]]$vmName,[string]$snapshotLabel){
    $vmClusterNodes=Get-ClusterGroup|?{$_.GroupType -eq 'VirtualMachine'}
    foreach ($vm in $vmName){
        $ownerNode=($vmClusterNodes|?{$vm -eq $_.Name}).OwnerNode
        if($ownerNode.State -eq 'Up'){
            $setSnapShotCommand={
                param($vm,$snapShotLabel)
                Checkpoint-VM -VMName $vm -SnapshotName $snapShotLabel
                }
            invoke-command -ComputerName $ownerNode.Name -ScriptBlock $setSnapShotCommand -Args $vm,$snapShotLabel
        }elseif($ownerNode){
            write-warning "$vm is currently owned by DOWNED node $($ownerNode.Name). No snapshots can be taken for such guest VM."
        }else{
            write-warning "$vm is does not match any Hyper-V Host in this cluster $((get-cluster).Name)"
            }
    }
}

takeVmSnapshot $vmNames $snapShotLabel