How to execute program on remote computer?

Several days ago I faced with a simple task - I had to execute program (automated QTP test in my case) on several remote computers.
My goal was simple - if I can execute scripts on my computer, then why don't we execute them on remote computers?


I think, this task is very interesting and practical, isn't it? :)

There was one condition. I tried to use "native" Windows solutions, which do not require additional installed software or libraries. I didn't want to use external soft, files, etc.

As a result, I found two solutions. Both of them use WMI:

1. Win32_Process Class
2. Win32_ScheduledJob Class

I will describe both of them.
Running ahead, I will say that I decided in favour of second solution (Win32_ScheduledJob class).


Let's explore these solutions, and compare them.
For clarity, I will show how to execute simple application (notepad.exe) on remote computer.

Execute program on remote computer with Win32_Process сlass
To create and start new process, I used Create method of the Win32_Process class.
VBScript code is simple enough:

1. strComputer = "."
2. strCommand = "notepad.exe"
3. 
   
4. Set objWMIService = GetObject("winmgmts:" & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")
5. Set objProcess = objWMIService.Get("Win32_Process")
6. 
   
7. errReturn = objProcess.Create(strCommand, null, null, intProcessID)
8. 
   
9. If errReturn = 0 Then
10. Wscript.Echo "notepad.exe was started with a process ID: " & intProcessID
11. Else
12. Wscript.Echo "notepad.exe could not be started due to error: " & errReturn
13. End If
    
    

String strComputer = "." means "local computer".
So, the result of notepad starting on my local computer was:

And notepad started on my computer! Great!

Then I tried execute my script on remote computer (I set strComputer = "servername"). The result was:

Script said, that the process was created.
Indeed, process was created. It was shown in Task Manager on remote computer:

But I didn't see it on a desktop of remote computer!
Further investigations shown, that:
For security reasons the Win32_Process.Create method cannot be used to start an interactive process remotely.

Win32_Process class is very useful to create and execute batch tasks on remote computer. But it can be applicable for interactive processes.

That's why I preferred the second way. I mean Win32_ScheduledJob сlass.


Execute program on remote computer with Win32_ScheduledJob сlass
By analogy, to create and start new process, I used Create method of the Win32_ScheduledJob class.
VBScript code is :

1. strComputer = "."
2. strCommand = "notepad.exe"
3. 
   
4. Const INTERVAL = "n"
5. Const MINUTES = 1
6. 
   
7. Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\root\cimv2")
8. Set objScheduledJob = objWMIService.Get("Win32_ScheduledJob")
9. Set objSWbemDateTime = CreateObject("WbemScripting.SWbemDateTime")
10. 
    
11. objSWbemDateTime.SetVarDate(DateAdd(INTERVAL, MINUTES, Now()))
12. errReturn = objScheduledJob.Create(strCommand, objSWbemDateTime.Value, False, 0, 0, True, intJobID)
13. 
    
14. If errReturn = 0 Then
15. Wscript.Echo "notepad.exe was started with a process ID: " & intJobID
16. Else
17. Wscript.Echo "notepad.exe could not be started due to error: " & errReturn
18. End If
    
    

Create method of Win32_ScheduledJob сlass creates new scheduled job on computer. (Hm... Have I said a tautology? :) ) In script I specified the time when scheduled job should be executed - in one minute from now. For that i used standard VBScript function - DateAdd.

Hint: Some time ago I wrote an article abount time/date functions in VBScript. Read it.

The result of execution was excellent! It created scheduled jobs both on local and remote computer.
This is result for remote computer is:

In one minute, the notepad was started and shown on desktop of remote computer!
I was happy :))

I hope, these two methods of remote application execution will be very helpful for you. Computer should calculate, human should think :)

So, I shown how to force your computers to work.
Do you have any ideas on how to force a human to think? :)

Summary:
If you have to run batch tasks, I think first method (Win32_Process Class) is simpler.
If you have to run interactive programs, use Win32_ScheduledJob Class.


--
Dmitry Motevich

From : http://motevich.blogspot.com/2007/11/execute-program-on-remote-computer.html