Set VM advanced options (stop ballooning)

deballoon.ps1

# VMware: set the advanced configuration option sched.mem.maxmemctl to zero to prevent ballooning
function deballoon ($vmname) {
  # Set "sched.mem.maxmemctl" to 0
  $opt = new-object Vmware.Vim.OptionValue -Property @{ Key = "sched.mem.maxmemctl"; Value = 0 }
  $vmConfigSpec = New-Object VMware.Vim.VirtualMachineConfigSpec
  $vmConfigSpec.extraconfig += $opt

  # Use a filter to find a particular VM
  $vm = get-view -viewtype "VirtualMachine" -filter @{ "Name" = $vmname }

  # And update the config on the server
  $vm.ReconfigVM( $vmConfigSpec )
}

connect-viserver -server virtualcenter -credential (Get-Credential (Get-Item env:username).value)
deballoon( "vm-name" )