Run invoke-command on multiple machines at the same time

Question

Hey all so I read that if I store my New-pssession in a variable then used that in my invoke-command it would run all computers at the same time.
$a = Get-Content "C:\Users\cody-horton\Desktop\list.txt"
$session
for($i=0;$i -lt $a.Length;$i++){
if(!(Test-Connection -Cn $a[$i] -BufferSize 16 -Count 1 -ea 0 -quiet)){
Write-Host $a[$i] -foregroundcolor red
else{
$session = New-PSSession $a[$i]
Invoke-Command -Session $session -FilePath "\\My computer\C`$\Users\public\Documents\zip folder.ps1"
What exactly am I doing wrong I just need to run this script on multiple machines at the same time.
Thanks.
Edit: Also what would be the best way to close all the sessions thanks.

Answer 1

Hi there,
So what I think you are doing wrong here is that you are overwriting the value in $Session everytime you executed code inside for loop. try the below:
$a = Get-Content "C:\Users\cody-horton\Desktop\list.txt"
$session = @() #define this as an array
for($i=0;$i -lt $a.Length;$i++){
if(!(Test-Connection -Cn $a[$i] -BufferSize 16 -Count 1 -ea 0 -quiet)){
Write-Host $a[$i] -foregroundcolor red
else{
$session += New-PSSession $a[$i] #add the new session to the array, at the end it will be a collection of sessions
Invoke-Command -Session $session -FilePath "\\My computer\C`$\Users\public\Documents\zip folder.ps1" #I think the above one won't work..first you need to copy the script locally on the machine and then execute it#Why this won't work because of Second-Hop Authentication
Have put comments where I edited your code.
Hope this helps
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