PowerShell - send variable via Invoke-Command

Question

I have 3 Windows 2016 servers and some routine task I want to automate. I'm newbie in PowerShell, so I spent a lot of time looking for answer in StackOverflow and "googling".

My task is to backup some files via 7zip on remote server.

There are is a command which works great:

Invoke-Command -ComputerName 10.10.0.20 -ScriptBlock {start-Process  -wait-FilePath 'C:\Program Files\7-Zip\7z.exe' -ArgumentList 'a','-t7z','C:\BlueCollar_backup\bluecollar_121.zip','C:\Services\BlueCollar' -wait}

But I need to add date to bluecollar_121.zip archive name, it should look like bluecollar_13.08.2018.zip

I've tried a huge amount of variants but with no luck.

[string]$stime = get-date -f 'dd.MM.yyyy
Invoke-Command -ComputerName 10.10.0.20 -ScriptBlock {start-Process -FilePath 'C:\Program Files\7-Zip\7z.exe' -ArgumentsList 'a -t7z C:\BlueCollar_backup\bluecollar_'$stime'.zip C:\Services\BlueCollar' -wait}

Second try was:

[string]$stime = get-date -f 'dd.MM.yyyy
[string]$tmp1="C:\BlueCollar_backup\bluecollar_$stime.zip"
$command = {start-Process -FilePath 'C:\Program Files\7-Zip\7z.exe' -ArgumentsList 'a -t7z $stime C:\Services\BlueCollar' -wait}

And the last try:

[string]$stime = get-date -f 'dd.MM.yyyy
$arguments = @()
$arguments += "a"
$arguments += "-t7z"
$arguments +=  "$tmp1"
$arguments +=  "C:\Services\BlueCollar"
Invoke-Command -ComputerName 10.10.0.20 -ScriptBlock {start-Process -FilePath 'C:\Program Files\7-Zip\7z.exe' -ArgumentList($arguments) -wait}

They all aren't working. The problem is $stime variable. How can I put variable $stime into Invoke-Command ?

UPD1: I solved that problem!

Invoke-Command -ComputerName '10.10.0.20' -ArgumentList  $stime -ScriptBlock{
$stime = $args[0]
start-Process -FilePath 'C:\Program Files\7-Zip\7z.exe' "a -t7z C:\BlueCollar_backup\bluecollar_$stime.zip C:\Services\BlueCollar" -wait
}

score 0 · Answer 1 · answered Sep 07 '18 at 16:49

The problem is that the computer you are executing the command from knows about the $stime variable, but the remote computer doesn't know it. So you have to pass it in.

There are a couple options, one is to use the $Using variable

[string]$stime = get-date -f 'dd.MM.yyyy
Invoke-Command -ComputerName 10.10.0.20 -ScriptBlock {
    start-Process -FilePath 'C:\Program Files\7-Zip\7z.exe' -ArgumentsList "a -t7z C:\BlueCollar_backup\bluecollar_$($Using:stime).zip C:\Services\BlueCollar" -wait
}

Another option that is perhaps a little cleaner looking is to make your ScriptBlock a string of text, and then pass it to the remote computer:

$ScriptBlock=[ScriptBlock]::Create("start-Process -FilePath 'C:\Program Files\7-Zip\7z.exe' -ArgumentsList 'a -t7z C:\BlueCollar_backup\bluecollar_$stime.zip C:\Services\BlueCollar'")
Invoke-Command -ComputerName 10.10.0.20 -ScriptBlock $ScriptBlock

An important distinction is between single quotes and double quotes. When you use single quotes, it resolves text exactly as is. When you use double quotes, it resolves variables.

Neither of variants didn't help, there is an error. Can not find parameter corresponding to parameter name: "ArgumentsList". + CategoryInfo : InvalidArgument: (:) [Start-Process], ParameterBindingException + FullyQualifiedErrorId : NamedParameterNotFound,Microsoft.PowerShell.Commands.StartProcessCommand + PSComputerName : 10.10.0.20 — Newbie21231, Sep 10 '18 at 07:56
I think it might be 'ArgumentList' instead of 'ArgumentSlist' — ErikW, Sep 11 '18 at 13:27

PowerShell - send variable via Invoke-Command

1 Answers1