Re: PowerCLI to change network from standard vSwitch to Distributed vSwitch

Although I don't understand why this can happen, you seem to have some NICs that are connected to a dvSwitch portgroup but that do not have a portkey. We can filter those out with a Where-clause.

See if this variation runs error-free

$nicTypes = "VirtualE100","VirtualE100e","VirtualPCNet32","VirtualVmxnet","VirtualVmxnet2","VirtualVmxnet3" 
$ports = @{}
$pgName = "MyPG"

# Get all the portkeys on the portgroup  
$pg = Get-VirtualPortGroup -Distributed -Name $pgName 
$pg.ExtensionData.PortKeys | %{$ports.Add($_,$pg.Name)}

# Remove the portkeys in use  Get-View 
$pg.ExtensionData.Vm | %{
    $nic = $_.Config.Hardware.Device | 
      where {$nicTypes -contains $_.GetType().Name -and $_.Backing.GetType().Name -match "Distributed"}
    $nic | where {$_.Backing.Port.PortKey} | %{$ports.Remove($_.Backing.Port.PortKey)}
}

# Assign the first free portkey 
$key = ($ports.Keys | Sort-Object)[0]
$key