MsTerminalServer.vbs - Microsoft Terminal Server monitoring using ActiveXperts Network Monitor
ActiveXperts Network Monitor ships with a powerful set of pre-defined checks. Each individual check has a static number of configuration items. To monitor other items, or to combine monitoring items, you can make use of custom VBScript checks.
Most of the built-in checks have a VBScript equivalent, implemented as a Function in a VBScript (.vbs) file. Out-of-the-box, each VBScript function monitors the same items as the built-in check. Feel free to modify a function. The VBScript check can be customized by editing the VBScript function.
To add a new VBScript-based Microsoft Terminal Server monitoring check, do the following:
- On the 'Monitor menu', click 'New Monitoring Check (VBScript)'. The 'VBScript Check' dialog box appears;
- In the 'File selection box', select 'MsTerminalServer.vbs';
- In the 'Function selection box', select 'CheckTerminalServer';
- In the 'Function parameters group box' enter the required parameters. You can also load a working sample first by clicking on the 'Load a sample, click here' link.
To customize the above monitoring check, click on the 'Edit button' next to the 'File selection box'. Notepad will be launched. You can now make changes to the VBScript function(s).

MsTerminalServer.vbs script source code
' /////////////////////////////////////////////////////////////////////////////// ' // ActiveXperts Network Monitor - VBScript based checks ' // © ActiveXperts Software B.V. ' // ' // For more information about ActiveXperts Network Monitor and VBScript, please ' // visit the online ActiveXperts Network Monitor VBScript Guidelines at: ' // https://www.activexperts.com/support/network-monitor/online/vbscript/ ' // ' /////////////////////////////////////////////////////////////////////////////// ' Option Explicit Const retvalUnknown = 1 Dim SYSDATA, SYSEXPLANATION ' Used by Network Monitor, don't change the names ' /////////////////////////////////////////////////////////////////////////////// ' // To test a function outside Network Monitor (e.g. using CSCRIPT from the ' // command line), remove the comment character (') in the following 5 lines: ' Dim bResult ' bResult = CheckTerminalServer( "localhost", "", 0, 0, 2 ) ' WScript.Echo "Return value: [" & bResult & "]" ' WScript.Echo "SYSDATA: [" & SYSDATA & "]" ' WScript.Echo "SYSEXPLANATION: [" & SYSEXPLANATION & "]" ' ////////////////////////////////////////////////////////////////////////////// ' ////////////////////////////////////////////////////////////////////////////// Function CheckTerminalServer( strComputer, strCredentials, nMaxActiveSessions, nMaxInactiveSessions, nMaxTotalSessions ) ' Description: ' Check Terminal Server sessions on a (remote) computer. Use network monitor service credentials to access the (remote) computer ' Parameters: ' 1) strComputer As String - Hostname or IP address of the computer you want to monitor ' 2) strCredentials As String - Specify an empty string to use Network Monitor service credentials. ' To use alternate credentials, enter a server that is defined in Server Credentials table. ' (To define Server Credentials, choose Tools->Options->Server Credentials) ' 3) nMaxActiveSessions As Number - Maximum number of Active Sessions allowed. 0 means: do not check Active Sessions ' 4) nMaxInactiveSessions As Number - Maximum number of Inactive Sessions allowed. 0 means: do not check Inactive Sessions ' 5) nMaxTotalSessions As Number - Maximum number of Total Sessions allowed. 0 means: do not check Total Sessions ' Usage: ' CheckTerminalServer( "", " ", MaxActiveSessions, MaxInactiveSessions, MaxTotalSessions ) ' Sample: ' CheckTerminalServer( "localhost", "", 0, 0, 2 ) Dim objWMIService CheckTerminalServer = retvalUnknown ' Default return value SYSDATA = "" ' Used to store session information SYSEXPLANATION = "" ' Set initial value If( Not getWMIObject( strComputer, strCredentials, objWMIService, SYSEXPLANATION ) ) Then Exit Function End If CheckTerminalServer = checkTerminalServerWMI( objWMIService, strComputer, nMaxActiveSessions, nMaxInactiveSessions, nMaxTotalSessions, SYSDATA, SYSEXPLANATION ) End Function ' ////////////////////////////////////////////////////////////////////////////// ' // ' // Private Functions ' // NOTE: Private functions are used by the above functions, and will not ' // be called directly by the ActiveXperts Network Monitor Service. ' // Private function names start with a lower case character and will ' // not be listed in the Network Monitor's function browser. ' // ' ////////////////////////////////////////////////////////////////////////////// Function checkTerminalServerWMI( objWMIService, strComputer, nMaxActiveSessions, nMaxInactiveSessions, nMaxTotalSessions, BYREF strSysData, BYREF strSysExplanation ) Dim objRefresher, objUtils, objItem Dim colItems Dim nActiveSessions, nInactiveSessions, nTotalSessions checkTerminalServerWMI = retvalUnknown ' Default return value set objRefresher = CreateObject("WbemScripting.SWbemRefresher") Set objUtils = CreateObject( "ActiveXperts.VbDebugger" ) nActiveSessions = -1 nInactiveSessions = -1 nTotalSessions = -1 On Error Resume Next Set colItems = objRefresher.AddEnum( objWMIService, "Win32_PerfFormattedData_TermService_TerminalServices").objectSet If( Err.Number <> 0 ) Then strSysData = "" strSysExplanation = "Unable to query WMI on computer [" & strComputer & "]" Exit Function End If If( objRefresher.Count <= 0 ) Then strSysData = "" strSysExplanation = "Win32_PerfFormattedData_TermService_TerminalServices class does not exist on computer [" & strComputer & "]" Exit Function End If On Error Goto 0 objRefresher.Refresh objUtils.Sleep 2000 objRefresher.Refresh For Each objItem in colItems nActiveSessions = objItem.ActiveSessions nInactiveSessions = objItem.InactiveSessions nTotalSessions = objItem.TotalSessions Next If( nActiveSessions = -1 OR nInactiveSessions = -1 OR nTotalSessions = -1 ) Then strSysData = "" strSysExplanation = "Unable to retrieve session counters" checkTerminalServerWMI = retvalUnknown Exit Function End If ' Set Data now strSysData = nActiveSessions strSysData = strSysData & "," strSysData = strSysData & nInactiveSessions strSysData = strSysData & "," strSysData = strSysData & nTotalSessions ' Check for Active Sessions if necessary If( nMaxActiveSessions > 0 AND nActiveSessions > nMaxActiveSessions ) Then strSysExplanation = "Currently " & nActiveSessions & " active sessions. Maximum allowed: " & nMaxActiveSessions & "." checkTerminalServerWMI = False Exit Function End If ' Check for Inactive Sessions if necessary If( nMaxInactiveSessions > 0 AND nInactiveSessions > nMaxInactiveSessions ) Then strSysExplanation = "Currently " & nInactiveSessions & " inactive sessions. Maximum allowed: " & nMaxInactiveSessions & "." checkTerminalServerWMI = False Exit Function End If ' Check for Total Sessions if necessary If( nMaxTotalSessions > 0 AND nTotalSessions > nMaxTotalSessions ) Then strSysExplanation = "Currently " & nTotalSessions & " sessions (total). Maximum allowed: " & nMaxTotalSessions & "." checkTerminalServerWMI = False Exit Function End If checkTerminalServerWMI = True strSysExplanation = "Active Sessions: " & nActiveSessions & "; Inactive Sessions: " & nInactiveSessions & "; Total Sessions: " & nTotalSessions & "." End Function ' ////////////////////////////////////////////////////////////////////////////// Function getWMIObject( strComputer, strCredentials, BYREF objWMIService, BYREF strSysExplanation ) On Error Resume Next Dim objNMServerCredentials, objSWbemLocator, colItems Dim strUsername, strPassword getWMIObject = False Set objWMIService = Nothing If( strCredentials = "" ) Then ' Connect to remote host on same domain using same security context Set objWMIService = GetObject( "winmgmts:{impersonationLevel=Impersonate}!\\" & strComputer &"\root\cimv2" ) Else Set objNMServerCredentials = CreateObject( "ActiveXperts.NMServerCredentials" ) strUsername = objNMServerCredentials.GetLogin( strCredentials ) strPassword = objNMServerCredentials.GetPassword( strCredentials ) If( strUsername = "" ) Then getWMIObject = False strSysExplanation = "No alternate credentials defined for [" & strCredentials & "]. In the Manager application, select 'Options' from the 'Tools' menu and select the 'Server Credentials' tab to enter alternate credentials" Exit Function End If ' Connect to remote host using different security context and/or different domain Set objSWbemLocator = CreateObject( "WbemScripting.SWbemLocator" ) Set objWMIService = objSWbemLocator.ConnectServer( strComputer, "root\cimv2", strUsername, strPassword ) If( Err.Number <> 0 ) Then objWMIService = Nothing getWMIObject = False strSysExplanation = "Unable to access [" & strComputer & "]. Possible reasons: WMI not running on the remote server, Windows firewall is blocking WMI calls, insufficient rights, or remote server down" Exit Function End If objWMIService.Security_.ImpersonationLevel = 3 End If If( Err.Number <> 0 ) Then objWMIService = Nothing getWMIObject = False strSysExplanation = "Unable to access '" & strComputer & "'. Possible reasons: no WMI installed on the remote server, no rights to access remote WMI service, or remote server down" Exit Function End If getWMIObject = True End Function