In this short post, I’ll explain one of the techniques to monitor whether a modem is listening for incoming calls on a machine, using Operations Manager 2007. Assuming that you may have some modems that get turned on when someone needs to dial in (for whatever reason), and *should* be disconnected afterwards. So you would like to get alerted when a modem is turned on and RRAS is configured to put the modem in listening mode.
This is how it works :
Create a Unit monitor – Scripting – Two state monitor
Target Windows Operating System. Keep the monitor disabled for now. Save the monitor in a custom management pack.
Schedule : run every 15 minutes or so
Script : choose a good name for the script (e.g. checkifmodemison.vbs) and set the timeout (1 minute should be ok)
Option Explicit
‘
‘ Script that runs an external tool and tries to
‘ determine if a modem is turned on and listening or not
‘ Written by Peter Van Eeckhoutte
‘ https://petersblog.dyndns.org:8899
‘ peter.ve@telenet.be
‘ Feb 2008
‘ version 1.0
Dim oArgs
Set oArgs = Wscript.Arguments
Dim oAPI
Dim objShell
Dim objScriptExec
Dim oBag
Dim modemturnedon
modemturnedon="false"
Set oAPI = CreateObject("MOM.ScriptAPI")
‘get args
If oArgs.Count < 2 Then
‘ If the script is called without the required arguments,
‘ create an information event and then quit.
Call oAPI.LogScriptEvent(Wscript.ScriptName,101,2,Wscript.ScriptName + " script was called without the necessary 2 arguments (<path to getmodemstatus.exe> <comport> and was not executed.")
Wscript.Quit -1
End If
Call oAPI.LogScriptEvent(Wscript.ScriptName,101,0,Wscript.ScriptName+" script was launched with " + Cstr(oArgs.Count) + " arguments.")
‘launch getmodemstatus
Set objShell = CreateObject("WScript.Shell")
Set objScriptExec = objShell.Exec(oArgs(0)+" "+oArgs(1))
modemturnedon= trim(objScriptExec.StdOut.ReadLine)
Set oBag = oAPI.CreatePropertyBag()
Call oBag.AddValue("ModemTurnedOn",modemturnedon)
Call oAPI.LogScriptEvent(WScript.ScriptName,101,0,WScript.ScriptName+" script completed successfully. ModemTurnedOn : "+modemturnedon)
Call oAPI.Return(oBag)
You can download the latest copy of the script from here :
Leave the parameters field empty for now.
Unhealthy expression :
Healthy expression :
Set the monitor health states
Set alerting properties
Save the monitor
On every host that needs to be monitored, you need to put a small executable : getmodemstatus.exe
Download from here
GetModemStatus.zip (2.3 KiB, 858 hits)
Create an override for the monitor, and select the server that needs to be monitored.
Enable the monitor and set the parameters as follows :
"<path to getmodemstatus.exe>" "comport where the modem is connected to"
Save the override. Wait until the management pack gets distributed and the script kicks in.
You should see the following 2 events when the script runs :
If the modem is turned on, the second event will show this in the description :
If everything has been set up, you should now get an alert in OpsMgr
If the modem is turned off again and RRAS does no longer grab the comport , the alert will be resolved (if that is how you’ve set up the alerting properties)
Enjoy !
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