PowerShell Get-Netadapter hangs

Question

I have a PowerShell script that is run at boot. It is designed for a small site server running on a Raspberry Pi3.

One of the things it does is reset the network settings. The following commands hang however in some situations.

$Adapter = Get-NetAdapter | ? {$_.Status -eq "up"}
$Interface = $Adapter | Get-NetIPInterface -AddressFamily "IPv4"
$Interface | Set-NetIPInterface -DHCP Enabled | Out-Null
$Interface | Set-DnsClientServerAddress -ResetServerAddresses | Out-Null

I was looking for any help as to why it might hang, a different way of coding resetting the Network Adaptor to DHCP or a way in which I can catch the hang (it does not error)

Answer 1

You didn't say what OS you are (were) running, but I'm going to assume Windows since you don't mention dotNet Core

This might be a CIM-vs-WMI issue, especially where you are querying hardware properties on the Pi. You might get better results using Get-WMIObject :

Get-WmiObject -Class "Win32_NetworkAdapter" -Filter "NetConnectionStatus=2"

• Win32_NetworkAdapter class describes the possible values for NetConnectionStatus, etc.

Answer 2

Haven't tried this on a Raspberry Pi, but you could shift this logic into a ScriptBlock and run it as a Job (aka a child process) which you could monitor for completion and kill/retry if it takes too long.

Example code:

$ResetAdapter = {
    ... your code here ...
}

$job = Start-Job -Name ResetAdapter -ScriptBlock $ResetAdapter

do {
  Start-Sleep -Seconds 1

  $Elapsed = ((Get-Date)-$job.PSBeginTime).TotalSeconds
} while (($job.State -eq "Running") -and ($Elapsed -lt 60))

if($job.State -eq "Running"){
  Stop-Job $job
  Remove-Job $job

  # try again?
}