Forum Discussion

John_Dodo's avatar
John_Dodo
Brass Contributor
Feb 24, 2022

AmbiguousParameterSet with ForEach-Object -parallel

Hello,   I have this error when trying to use parallele tasks. Can anybody help on this please?         $TimeDuration = [System.Diagnostics.Stopwatch]::StartNew() [System.Collections.ArrayLi...
powershell
Windows PowerShell
John_Dodo's avatar
John_Dodo
Brass Contributor
Feb 24, 2022
Normally $pingtest always is at true or false
[DBG]: PS C:\Users\xxx> $pingtest
True
Regarding $complist it is indeed filled. BUT, sometimes one of the property can be empty sometimes.
[DBG]: PS C:\Users\xxxx> $complist
Description : WS2016 - DC
DistinguishedName : CN=XXX,OU=Domain Controllers,DC=unich,DC=net
DNSHostName : XXX
Enabled : True
Name : XXX
ObjectClass : computer
ObjectGUID : 2b85de89-1886-409c-92e0-1c7a97a6be48
OperatingSystem :
SamAccountName : XXX$
SID : S-1-5-21-1128282684-3729639265-1475195819-26153
UserPrincipalName :

Could that explain the problem ? Again without the -parallel the values of pingtest and the emptiness of properties is still the same, but seems to work.
Harm_Veenstra's avatar
Harm_Veenstra
MVP
Feb 24, 2022
You could put in a check for the values before adding them to the array. Certain values are always present in AD but things like Description is a free text field. Perhaps something like
if ($Null -eq $_.Description) {$_.Description='Empty'}
  • John_Dodo's avatar
    John_Dodo
    Brass Contributor
    Feb 24, 2022
    I just modified my script to only test on 1 computer. I made sure this computer has all values filled.
    Still, without the -parallel it works but with it it fails. Could it be that I can't use $_. with -parralel, from what I saw it should be feasible.

    Details :
    $complist = Get-ADComputer -Filter * -Property OperatingSystem,name,enabled,Description,distinguishedname | Select-Object OperatingSystem,name,enabled,Description,distinguishedname | Where-Object -Property name -EQ "PCNAME"

    F8 on $complist :
    [DBG]: PS C:\Users\bodig-adm> $complist

    OperatingSystem : Windows Server 2008 R2 Standard
    name : PCNAME
    enabled : True
    Description : UVS - File & Print
    distinguishedname : CN=PCNAME,OU=CH - Servers,OU=CH,OU=XXX,DC=XXX,DC=XXX

    So the properties have value.

    Then foreach-object works but -parrallel fails
    8 | $ArrayWithHeader.add([pscustomobject]@{'OS'=$_.OperatingS …
    | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    | You cannot call a method on a null-valued expression.

    I will try to use intermediate variables...
    • John_Dodo's avatar
      John_Dodo
      Brass Contributor
      Feb 24, 2022
      $complist | ForEach-Object {

$PC = $_.name
$OS = $_.OperatingSystem
$DN = $_.distinguishedname
$enable = $_.enabled
$desc = $_.Description
Write-Host "test"
write-host "working on $PC, $OS, $DN, $Enable, $desc, $count/$total"

$pingtest = Test-Connection -ComputerName $PC -Quiet -Count 1 -ErrorAction SilentlyContinue
write-host "$pingtest"
#$ArrayWithHeader.add([pscustomobject]@{'OS'=$_.OperatingSystem;'Computer_Name'=$_.name;'DN'=$_.distinguishedname;'enabled'=$_.enabled;'Description'=$_.Description;'Reacheable'=$pingtest})
$tutu = [pscustomobject]@{'OS'=$OS;'Computer_Name'=$PC;'DN'=$DN;'enabled'=$enable;'Description'=$desc;'Reacheable'=$pingtest}
Write-Host $tutu
$ArrayWithHeader.add($tutu)
$count += 1
}

      In both cases my variables are filled, but -parrallel gives an error. I know that in PS5 I had an error when trying to use ArrayWithHeader.add($tutu) (though it was with foreach -parrallel (not foreachobject)

       

Resources