Passing parameters

PowerShell Help
1

I am making the following call

.\script.ps1 -value ‘value’

This works

param([string]$value)
Write-Output $value
powershell.exe -ExecutionPolicy Bypass -Command {invoke-command -file \server\script.ps1 -computername computer -argumentlist “value”}

this does not

param([string]$value)
powershell.exe -ExecutionPolicy Bypass -Command {invoke-command -file \server\script.ps1 -computername computer -argumentlist $value}

What am I doing wrong? Why can’t I get the parameter to pass though?

Write-Output $value, does issue the proper value, but for some reason it is not liked in the second script. I would think that this should be super simple, but it is driving me mad.

2

When you call out to powershell.exe, all of your variables are basically converted to strings. Since you’re already in powershell, why not just call Invoke-Command directly?

param([string]$value)
invoke-command -file \\server\script.ps1 -computername computer -argumentlist $value
3

It’s an issue of scope. Check out the Secrets of Powershell Remoting in the eBooks link above. Basically, you need to pass the variable as using:$value (assuming you are using Powershell V3 or above). Take a look at this as well: http://powershell.com/cs/blogs/tips/archive/2012/06/18/running-a-script-block-with-parameters.aspx

4

That shouldn’t matter; he’s passing $value to the -ArgumentList parameter, which is fine.

5

I’m wondering, like Dave, why the call to powershell.exe inside of powershell. Aside from that, I don’t think you can pass parameters to powershell.exe’s -Command script block. You can build a string like so:

powershell.exe -ExecutionPolicy Bypass -Command ""
6

I was using the other command because it was getting me around the

invoke-command : File \server\script.ps1 cannot be loaded because you have elected to not run this software now.

message.

Setting Set-ExecutionPolicy Bypass on the remote machine doesn’t seem to help me get passed not signing the scripts.

Thanks for your help though. It is very much appreciated.

7

That’s odd. I didn’t think your local ExecutionPolicy should matter to Invoke-Command. I wonder if that’s a bug, maybe you can get around it like this:

param([string]$value)
$scriptContent = Get-Content \\server\script.ps1 -Raw
invoke-command -ScriptBlock $scriptContent -computername computer -argumentlist $value
8

Invoke-Command : Cannot bind parameter ‘ScriptBlock’. Cannot convert the “My script contents” value of type “System.String” to type “System.Management.Automation.ScriptBlock”.
At E:\script.ps1:9 char:29

  • invoke-command -ScriptBlock $scriptContent -computername server -argumentlist …
  •                         ~~~~~~~~~~~~~~
    • CategoryInfo : InvalidArgument: (:slight_smile: [Invoke-Command], ParameterBindingException
    • FullyQualifiedErrorId : CannotConvertArgumentNoMessage,Microsoft.PowerShell.Commands.InvokeCommandCommand
9

For whatever reason the forum ate my snippet and won’t let me post it.

10

I don’t think you can invoke a script that resides on a UNC path with invoke-command to a remote computer due to Kerberos double hop limitations.

What I’ve done when I’ve needed to do this interactively (generally use group policy to do stuff like that):

Copy-Item \\server\script.ps1 \\computer\C$\
Invoke-Command -Computer Computer -FilePath 'C:\script.ps1'
11

oops, forgot that you can’t directly cast strings to ScriptBlocks, have to call the Create method:

param([string]$value)
$scriptContent = Get-Content \\server\script.ps1 -Raw
invoke-command -ScriptBlock ([scriptblock]::Create($scriptContent)) -computername computer -argumentlist $value
12

Dave Wyatt,

I owe you a beer.

Thank you so much for helping me out with this.