Q. for Sys Admins: how programmatically find User Names currently logged onto a network server?

[IlyaRabyy]

Colleagues,
The subject line says it.
I hope there is at least one Sys Admin among you?

AHWBGA!

Regards,

Ilya

 

[strongm]

You want a list of every user currently logged in to the domain? Sadly (and perhaps surprisingly) AD does not track this info. Or just those users logged on to a particular server? If the latter, then something like

[COLOR=blue]        Dim searcher As New ManagementObjectSearcher("\\yourservername\root\cimv2", "SELECT * FROM Win32_ComputerSystem")
        Dim queryCollection As ManagementObjectCollection = searcher.Get()

        For Each queryObj As ManagementObject In queryCollection
            MsgBox($"Logged in user: {queryObj("UserName")}")
        Next[/color]

You need to import [tt]System.Management[/tt] (and it is possible you will first have to add this package through NuGet)

 

[IlyaRabyy]

Regards,

Ilya

 

[strongm]

As I said: "it is possible you will first have to add this package through NuGet

 

[IlyaRabyy]

Alrite, I found and added System.Management package to the Project.
Code:

Dim searcher As New ManagementObjectSearcher("\\yourservername\root\cimv2", "SELECT * FROM Win32_ComputerSystem")
Dim queryCollection As ManagementObjectCollection = searcher.Get()

erred:

The MS Help at

https://learn.microsoft.com/en-us/t...logon/not-log-on-error-rpc-server-unavailable

isn't much of a help...



What else am I missing?

Regards,

Ilya

 

[strongm]

Er... You need to replace [tt]yourservername[/tt] with the actual name of your server ...

 

[IlyaRabyy]

Done.
(Well, not server but my own WS, its name's redacted.)

Dim searcher As New ManagementObjectSearcher("\\XXXXXXXXXXXXX\root", "SELECT * FROM Win32_ComputerSystem") ' \\An2PreODSApp001\root\cimv2
Dim queryCollection As ManagementObjectCollection = searcher.Get()
Dim lsLogStr As String = ""

For Each queryObj As ManagementObject In queryCollection
'	MsgBox($"Logged in user: {queryObj("UserName")}")
	lsLogStr += queryObj.ToString() + vbCrLf
Next

Errs on Next:

I would understand if it erred on lsLogStr += statement, but on Next...

Regards,

Ilya

 

[strongm]

>I would understand
Essentially you are trying to enumerate an empty ManagementObjectCollection (because you edited the search scope incorrectly). Thus [tt]Next[/tt] fails, since there is nothing to enumerate (this is a simplified explanation)

Mind you, when you DO get the emnumeration working then I don't think that lsLogStr will contain what yyou think, as you are converting an entire object to a displayable string, and not just the Username

[COLOR=blue]Dim searcher As New ManagementObjectSearcher("\\YOURSERVERNAME\root[b][COLOR=red]\cimv2[/color][/b]", "SELECT * FROM Win32_ComputerSystem") ' 
Dim queryCollection As ManagementObjectCollection = searcher.Get()
Dim lsLogStr As String = ""

For Each queryObj As ManagementObject In queryCollection
    lsLogStr += [b][COLOR=red]queryObj("UserName").ToString() + vbCrLf[/color][/b]
Next[/color]

 

[IlyaRabyy]

Adding "\cimv2" worked, but it returned only the name of my W/S.
Well, obviously, coz I test it on my W/S.
But it doesn't list my UN...
Currently, I have this code (in my test program):

Dim searcher As New ManagementObjectSearcher("\\XXXXXXXXX\root\[COLOR=#CC0000][b]cimv2[/b][/color]", _
					"SELECT * FROM Win32_ComputerSystem")
Dim queryCollection As ManagementObjectCollection = searcher.Get()
Dim lsLogStr As String = ""

For Each queryObj As ManagementObject In queryCollection
	lsLogStr += queryObj.ToString() + vbCrLf
Next

What else am I missing?

On the footnote: I've always been End User/Desktop Applications programmer, never System Programmer, all this stuff is totally new to me! So I truly appreciate your patience, Master StrongM! (No pun intended whatsoever, I'm dead serious!)

Regards,

Ilya

 

[strongm]

You didn't apply all my corrections, so what you are returning is 1) indeed not the username but 2) neither is it the W/S name. What your are returning, as previously explained, is the stringified name of the object you are using (a specific instance of the WMI Win32_ComputerSystem class - this string may look somewhat like your W/S name, but actually is not). Look at my code again, and use the second correction in red as well as the first.

 

[IlyaRabyy]

Rite!
queryObj("UserName") did the trick! (My apologies, I've overlooked it...)
Thank you!

Regards,

Ilya

 

[IlyaRabyy]

Here's the function I programmed based on the StrongM's recommendations.
Please review and advise: have I missed anything still (especially in the parameter verification part)?

'====================================================================================================================================
Public Function GetUserNames(ByVal tcMachineName) As String
'====================================================================================================================================
' Purpose       : Returns the list of the User Names currently logged into the givem machine.
' Description   : Engages ManagementObject[Collection] class[es] to query system logs for the currently logged in User Names.
' Parameters	: The Machine name.
' Returns	: List of the User Names, separated by CRLF, currently logged into the given machine.
' Side effects  : None.
' Notes         : 1. Generic.
'                 2. Complies with .NET Framework ver. 1.1 and higher.
'		  3. On error, returns the error description, which starts with "Error occurred" phrase.
' Author        : Ilya I. Rabyy
' Revisions     : by Ilya on 2024-04-09 - started 1st draft.
'====================================================================================================================================
Dim lsLogStr As String = ""

' Parameter verification
If (TypeOf tcMachineName IsNot String) Then
	lsLogStr = "Error occurred: the Machine Name parameter is not of type String!"
	Return lsLogStr
End If

Dim lcMachineName As String = Strings.Trim(tcMachineName)

If String.IsNullOrEmpty(lcMachineName) Then
	lsLogStr = "Error occurred: the Machine Name parameter must not be empty!"
	Return lsLogStr
End If

' Format the Machine Name
If Not Left(lcMachineName, 2) = "\\" Then
	
	If Not Left(lcMachineName, 1) = "\" Then
		lcMachineName = "\\" + lcMachineName
	Else
		lcMachineName = "\" + lcMachineName
	End If ' Not Left(lcMachineName, 1) = "\"

End If ' Not Left(lcMachineName, 2) = "\\"

lcMachineName = AddBackSlash(lcMachineName)

' Parameter's been validated (it seems).
' Let's get digging! But keep in mind that if it's a network server, it might be unavailable, hence Try-Catch-EndTry construct.
Try
	Dim loSearcher As New ManagementObjectSearcher(lcMachineName + "root\cimv2", "SELECT * FROM Win32_ComputerSystem")
	Dim loQueryCollection As ManagementObjectCollection = loSearcher.Get()

	For Each loQueryObj As ManagementObject In loQueryCollection
		lsLogStr += loQueryObj("UserName").ToString() + vbCrLf
	Next
Catch loErr As Exception
	lsLogStr = Read_Exception(loErr)
End Try

Return lsLogStr

End Function
'====================================================================================================================================

Regards,

Ilya