ToolMaking MOL chapter 16.2 question about switching to WMI

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by etolleson at 2013-02-14 06:57:39

I am new to PS finished the book PV3 MOL and felt pretty good until now, I am letting myself get stuck on the "‘Switching to WMI’ section of 16.2 in the book ToolMaking MOL page 164" for some reason I am not able to get
Invoke-WmiMethod -Class Win32_OperatingSystem -Name REBOOT -ComputerName localhost to work I have tried several different things. I can get the Invoke-WmiMethod command to work with the help EXAMPLE 2 (notepad) in PS. I am having trouble understanding the error. I tried replacing the code in "listing 16.1" with this code and still no luck. Can you give me sugestions about Invoke-WmiMethod command and ways to troubleshoot the Error that I am receiving and having trouble deciffering fo rsome reason it is:
Invoke-WmiMethod : Invalid method Parameter(s)
At line:1 char:1
+ Invoke-WmiMethod -Class Win32_OperatingSystem -Name REBOOT -ComputerName localho …
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation: (:slight_smile: [Invoke-WmiMethod], ManagementException
+ FullyQualifiedErrorId : InvokeWMIManagementException,Microsoft.PowerShell.Commands.InvokeWmiMethod
by etolleson at 2013-02-14 09:51:39
I found this to work but not really sure why and if it was what the author was suggesting
Get-WmiObject -Class win32_operatingSystem -ComputerName server | Invoke-WmiMethod -name REBOOT
if so great if not what should I have done. Trying to gain a better understanding of how to work with PS and WMI for older version of OS.
by MattG at 2013-02-14 16:36:43
Great questions. The reason your first example doesn’t work is because the Reboot method is an instance method meaning that you must invoke it from an instance of a WMI class - Win32_OperatingSystem in your case. As to why this method is not static I don’t know considering you will only ever get a single instance of a Win32_OperatingSystem class as far as I know. For your first example to work properly, you must call a static method. A good example of a static WMI method is Create in Win32_Process. To illustrate this, observe the following examples:
Invoke-WmiMethod -Class Win32_Process -Name Create -ArgumentList calc.exe -ComputerName localhostand the CIM cmdlet PSv3 equivalent:
Invoke-CimMethod -Class Win32_Process -Name Create -Arguments @{CommandLine='calc.exe'}To more clearly illustrate that Reboot requires an instance of the Win32_OperatingSystem class observe the following:
$OperatingSystemInstance = Get-WmiObject -Class Win32_OperatingSystem
$OperatingSystemInstance.Reboot()I hope this helps answer your questions.
by etolleson at 2013-02-15 06:14:42
Matt thanks for the response. The calc works great and I think I understand the instance that needs to be created. When I first tried the reboot it gave me an error which I found out you could not run it on the localhost or it appears that way anyway as long as I specified a different computer name in the instance it work like a charm. Thanks again for you help.

Exception calling "Reboot" : "Privilege not held. "
At line:1 char:1
+ $OperatingSystemInstance.Reboot()
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:slight_smile: , MethodInvocationException
+ FullyQualifiedErrorId : WMIMethodException