$Datastores = @"
VMTEST2_1_A9K_SYS
"@
$Datastores = ConvertTo-Array -MultiLineString $Datastores
 
foreach ($Datastore in $Datastores) {
    $Datastore = Get-Datastore $Datastore
    $VMhosts = $Datastore | Get-VMHost
    $canonicalName = $Datastore.ExtensionData.Info.Vmfs.Extent[0].DiskName
    $lunUuid = (Get-ScsiLun -VmHost $VMhosts | Where-Object { $_.CanonicalName -eq $canonicalName }).ExtensionData.Uuid | Select-Object -First 1
    $storSys = Get-View $VMhosts.ExtensionData.ConfigManager.StorageSystem
    $device = $storSys.StorageDeviceInfo.ScsiLun | Where-Object { $_.CanonicalName -eq $canonicalName }
    #unmount disk
    if ($device.OperationalState[0] -eq 'ok') {
        $storSys.UnmountVmfsVolume($Datastore.ExtensionData.Info.Vmfs.Uuid)
    }
    #detach disk
    $storSys.DetachScsiLun($lunUuid)
    #rescan hosts
    foreach ($VMhost in $VMhosts) {
        Get-VMHost $VMhost | Get-VMHostStorage -RescanAllHba -RescanVmfs
    }
}