I'm trying to write a powershell script that will take a list of commands and then run them on a remote machine, I have the following code:
foreach($command in $commands)
{
Invoke-Command -computer "BNEBAK" -scriptblock{"$command"}
}
Which does not throw any error but also does not actually run the command (e.g stop-service servicename). $commands is read in from a text file passed as an argument when the script is called, I know the rest of this script works because I have been using it to do local commands with Invoke-Expression for some time.
Any help would be fantastic.
The correct code would be
$commands = #(get-content com.txt)
for($command in $commands) {
$scriptblock = $ExecutionContext.InvokeCommand.NewScriptBlock($command)
Invoke-Command -computer $computer -scriptblock $scriptblock
}
Related
$Computerlist = get-content maintptr.txt
foreach ($computer in $ComputerList) {
Invoke-Command -ComputerName $computer -Scriptblock {RUNDLL32 PRINTUI.DLL,PrintUIEntry /ga /n\\ServerName\QueueName}
}
some of the computers did not install the queue, but PowerShell does not generate error messages when running the script. I would like to know which computer failed. When running the line without variables, running each computer, PowerShell does generate errors, but when run in a script, it does not.
I'm trying to run a command on a VM using Invoke-Command. The command should stop a program that processes jobs after it finishes its current job. It works if I run it in the terminal using RDC.
& 'C:\Program Files\Autodesk\Vault Client 2021\Explorer\JobProcessor.exe' /stop
But if I run it from a different machine using Invoke-Command nothing seems to happen.
$session = New-PSSession -ComputerName 'hostname' -Credential (Get-Credential)
Invoke-Command -Session $session -ScriptBlock {
& 'C:\Program Files\Autodesk\Vault Client 2021\Explorer\JobProcessor.exe' /stop
}
However Process Monitor shows the command come in for both cases, but the program is still running.
I have also tried using Start-Process with the same result, i.e. it works in the terminal on the VM but not using Invoke-Command.
Start-Process -FilePath 'C:\Program Files\Autodesk\Vault Client 2021\Explorer\JobProcessor.exe' -ArgumentList '/stop'
I've been stuck for many days and I've exhausted my googlable knowledge for this problem.
Are you sure that file exists on the remote computer?
For simplicity, I rewrote your command to a known executable that is always there in Windows and returns unique info for any given computer.
C:\> & 'C:\Windows\system32\HOSTNAME.EXE'
server1
C:\> icm {& 'C:\Windows\system32\HOSTNAME.EXE'}
server1
C:\> icm {& 'C:\Windows\system32\HOSTNAME.EXE'} -ComputerName server2
server2
Here's your script with some error handling.
$session = New-PSSession -ComputerName 'hostname' -Credential (Get-Credential)
Invoke-Command -Session $session -ScriptBlock {
$exe = 'C:\Program Files\Autodesk\Vault Client 2021\Explorer\JobProcessor.exe'
$ok = Test-Path $exe
if ($ok) {& $exe /stop} else {
Write-Warning "EXE not present on $($env:COMPUTERNAME)!"
}
}
Learn how to add error handling and you'll be well on your way to solving your problems faster and getting more stuff done.
I start with a txt file named vms.txt.
It contains 2 servers like so:
server1
server2
When I run the script shown below, the command that is invoked to install VMware tools only runs on server2 and server1 gets skipped. Does anyone have any suggestions on how to modify this script to make it run on both servers in the txt file? I will have to run this in the future for hundreds of VMs, so I am trying to find an easy way to get this to loop properly.
$cred = Get-Credential
$vms = Get-Content C:\Scripts\Tools\vms.txt
foreach($vm in $vms){
$sessions = New-PSSession -ComputerName $vm -Credential $cred
}
foreach($session in $sessions)
{
Invoke-Command -Session $session -ScriptBlock {
c:\users\jsmith\documents\VMware-tools-10.3.5.exe /v "/qn REBOOT=R Remove=AppDefense,VMCI”
}
}
In your loop-based approach, the problem is your variable assignment:
# !! This only ever stores the *last* session created in $sessions,
# !! because the assignment is performed in *each iteration*.
foreach($vm in $vms){
$sessions = New-PSSession -ComputerName $vm -Credential $cred
}
The immediate fix is to move the assignment out of the loop:
# OK - captures *all* session objects created in $sessions
$sessions = foreach($vm in $vms){
New-PSSession -ComputerName $vm -Credential $cred
}
Taking a step back:
Both New-PSSession -ComputerName and Invoke-Command -Session accept an array of computer names / sessions, so there's no need for loops.
Passing multiple sessions / computer names to Invoke-Command has the big advantage that the operations run in parallel.
Note:
Invoke-Command has built-in throttling to avoid targeting too many machines at once. It defaults to 32, but can be modified with the -ThrottleLimit parameter.
Output from the targeted computers will arrive in no predictable order, but the output objects are decorated with (among others) a .PSComputerName property reflecting the originating computer - see the bottom section of this answer.
That is, your code can be simplified to:
$cred = Get-Credential
$vms = Get-Content C:\Scripts\Tools\vms.txt
$sessions = New-PSSession -ComputerName $vms -Credential $cred
Invoke-Command -Session $sessions -ScriptBlock {
c:\users\jsmith\documents\VMware-tools-10.3.5.exe /v "/qn REBOOT=R Remove=AppDefense,VMCI”
}
Important:
Sessions should eventually be cleaned up with Remove-PSSession when no longer needed.
However, that stops any commands running in those sessions, so if you've launched asynchronous operations via your Invoke-Command call, you need to ensure that those operations have finished first - see the comments re potentially asynchronous execution of your VMware-tools-10.3.5.exe application below.
Or, even simpler, if you only need to execute one command on each machine, in which case there is no need to create sessions explicitly, pass all computer names directly to Invoke-Command's -ComputerName parameter:
$cred = Get-Credential
$vms = Get-Content C:\Scripts\Tools\vms.txt
# Note the use of -ComputerName
Invoke-Command -ComputerName $vms -Credential $cred -ScriptBlock {
# Note the use of | Write-Output to ensure synchronous execution.
c:\users\jsmith\documents\VMware-tools-10.3.5.exe /v "/qn REBOOT=R Remove=AppDefense,VMCI” | Write-Output
}
Important:
If your application (VMware-tools-10.3.5.exe) runs asynchronously, you must ensure its
synchronous execution, otherwise it may not run to completion, because the implicitly created remote session is discarded when a script block returns from a given computer.
A simple trick to ensure synchronous execution of any external (GUI-subsystem) executable is to pipe it to Write-Output, as shown above (or Wait-Process, if it doesn't produce console output) - see this answer for an explanation.
I am trying to invoke a remote bat file from my local machine that should start and run the bat in a remote machine terminal. My script is able to connect and show me the output. However, it is invoking the remote bat file but waiting on my screen with bat file output. and my idea is the bat file should invoke and running in the remote machine rather than showing the output on my terminal local terminal. What should be the way here?
loop{
Invoke-Command -ComputerName $computer -credential $cred -ErrorAction Stop -ScriptBlock { Invoke-Expression -Command:"cmd.exe /c 'C:\apacheserver.bat'" }
}
From what I understand you want the .bat file to not show you the result. If so, you should do it with the Out-Null or by redirecting STDOUT and STDERR to NULL.
IE: Invoke-Expression -Command:"cmd.exe /c 'C:\apacheserver.bat'" | Out-Null
If I'm understanding correctly, you want to suppress the output from the .bat file inside your local console? If so, redirecting to some form of $null is the way to go. You also shouldn't need Invoke-Expression as Invoke-Command can run the file directly:
Invoke-Command -ComputerName $computer -Credential $cred -ErrorAction Stop -Scriptblock {
cmd.exe /c 'C:\apacheserver.bat' | Out-Null
}
You could also use > $null instead of Out-Null if you prefer.
If you want to redirect the output of the Invoke-Command call to the remote console instead, that kind of defeats the purpose of the cmdlet. You could try redirecting the console output to a file on the remote computer if you want a local record:
$remoteFile = '\\server\C$\Path\To\Output.txt'
Invoke-Command -ComputerName $computer -Credential $cred -ErrorAction Stop -Scriptblock {
cmd.exe /c 'C:\apacheserver.bat' > $remoteFile
}
If I understand you, you want to run the script in the background and not wait for it:
Invoke-Command $computer -Credential $cred { start-process C:\apacheserver.bat }
Here's a sample script that attempts to create a remote session on a server, then use WMI to get a list of the server's IIS application pools, and list their names:
function Test-Remoting
{
[CmdletBinding()]
param
(
)
begin
{
Enter-PSSession TestServer
$appPools = Get-WmiObject -namespace "root\MicrosoftIISv2" -class "IIsApplicationPool" -Authentication 6
$appPools | ForEach-Object {
$appPool = $_;
$appPool.Name
}
Exit-PSSession
}
}
This function is contained in a file called "Test-Remoting.ps1." I open up PowerShell, CD into the directory that contains this file, dot-source the file in, and call the function:
PS C:\Users\moskie> . .\Test-Remoting.ps1
PS C:\Users\moskie> Test-Remoting
But the result of this script is a list of the application pools on my local machine, and not TestServer.
Alternatively, if I run the following lines (identical to the ones in the function) manually at the PowerShell prompt, I do get the list of app pools on the remote server:
PS C:\Users\moskie> Enter-PSSession TestServer
[TestServer]: PS C:\> $appPools = Get-WmiObject -namespace "root\MicrosoftIISv2" -class "IIsApplicationPool" -Authentication 6
[TestServer]: PS C:\> $appPools | ForEach-Object { $appPool = $_; $appPools.Name }
<a list of the names of the application pools on TestServer>
[TestServer]: PS C:\>
I think there's a concept I'm oblivious to, regarding PowerShell remoting and scope. Can anyone help explain this behavior?
I believe Enter/Exit-PSSession is meant more interactive use. From the Enter-PSSession help:
SYNOPSIS
Starts an interactive session with a remote computer.
In a script, use New-PSSession and Invoke-Command like so:
$session = New-PSSession server01
Invoke-Command -Session $session {hostname}
Remove-PSSession -Session $session
Update: To execute a complete script remotely use the FilePath parameter on Invoke-Command:
icm server01 -FilePath C:\users\keith\myscript.ps1 -arg 1,2
This will copy the script to the remote computer server01 and execute it there with the supplied parameters.