Powershell remoting via PSSESSION and variables

[kmcferrin]

So I have some code that allows me to open a remote session via PSSession and execute some code in a scriptblock. I can pass local variables to the scriptblock for use in the remote execution via "-Args". That works great. But now I need to retrieve a variable that is created in the scriptblock on the remote host so I can check it's value locally. Sample code below:

$RemoteHost = "server.fqdn.com"

# This function calls external executables, waits for them to complete and returns the exit code
function Run-RemoteProcess ($cmd, $Parameters) {
    $RemoteSession = New-PSSession -ComputerName $Remotehost
    #Enter-PSSession -session $RemoteSession
    Invoke-Command -Session $RemoteSession -Scriptblock {param($cmd,$Parameters)
        $Process = New-Object System.Diagnostics.Process;
        $Process.StartInfo = New-Object System.Diagnostics.ProcessStartInfo;
        $ExitCode = $false;
        $Process.StartInfo.FileName = $cmd;
        $Process.StartInfo.Arguments = $Parameters;
        $Process.StartInfo.UseShellExecute = $shell;
        $Process.StartInfo.WindowStyle = 1;
        $null = $Process.Start();
        $Process.WaitForExit();
        $Global:ExitCode = $Process.ExitCode;
        $Process.Dispose();
    } -Args $cmd,$Parameters
    #Exit-PSSession
    #Remove-PSSession $RemoteSession
    If ($Process.ExitCode -ne 0) {
        #Log an error
        #Sets performance counter State to Warning
        #$PerfCounterState = new-object 
    }
    Else {
        #Logs success
    }
    #$PerfCounterData.Increment()
    return $ExitCode
}

"Returncode = " + $Returncode
$ReturnCode = Run-RemoteProcess ping.exe "-n 10 192.168.199.199"

I can't seem to get the $Exitcode value to work. I have very similar code that works great as a local function. If I leave the PSSession open after the script completes, I can "Enter-PSSession $RemoteSession" and check the value of $Exitcode, and it has the correct data there. So I know that it is getting set in the remote session to the correct exit code value for the .EXE command that it runs. I just need to get that value back from the remote host somehow.

________________________________________
CompTIA A+, Network+, Server+, Security+
MCTS:Windows 7
MCSE:Security 2003
MCITP:Server Administrator
MCITP:Enterprise Administrator
MCITP:Virtualization Administrator 2008 R2
Certified Quest vWorkspace Administrator

 

[kmcferrin]

I figured it out. I had to make three changes:

Change1:

Invoke-Command -Session $RemoteSession -Scriptblock

becomes

$Result = Invoke-Command -Session $RemoteSession -Scriptblock

Change2:
Insert "$ExitCode;" on a new line before the line that says

$Process.Dispose();

Change3:
Change the line that reads

return $ExitCode

to read

return $Result

Apparently using PSSession the $Result variable is assigned the output of the "Invoke-Command" command. In order for $Result to get the exit code you just need to echo the value of $ExitCode to the console in the remote session, then it get's assigned to $Result and can be returned from the function to the main script.


________________________________________
CompTIA A+, Network+, Server+, Security+
MCTS:Windows 7
MCSE:Security 2003
MCITP:Server Administrator
MCITP:Enterprise Administrator
MCITP:Virtualization Administrator 2008 R2
Certified Quest vWorkspace Administrator