Add SNMP Traffic sensor

[lossi771]

What's going on?

Hello,
I am trying to configure a SNMP Traffic sensor on a specific interface of a network device.
For the moment my C# script looks like this:

snmpTrafficTargets = client.Targets.GetSensorTargets(77154, "snmptraffic");
var targetInterface = snmpTrafficTargets.FirstOrDefault(i =>
  {
    var parts = i.Name.Split(' ');
    return parts.Length > 1 && parts[1].Equals(t.LocalInterface);
  }
if (targetInterface != null)
  {
    var p = new RawSensorParameters($"Interface {t.LocalInterface}", "snmptraffic");
    string rawId = targetInterface.Value;
    p["interfacenumber_check"] = rawId;
    client.AddSensor(77154, p);
  }

From the web server logs I can see the following request:
POST /addsensor5.htm aliasavailable=&anti-csrf-token=***&errorintervalsdown_=1&id=77154&inherittriggers=1&"interfacenumber__check=7:7|(007) 7 Traffic|Connected|100 MBit/s|Ethernet|1|7|100000000|3|1|"&interfacenumber_=1&interfacenumber_=1&"interval_=60|60 seconds"&intervalgroup=0&intervalgroup=1&monitorstate_=0&"name=Base Sensor 1"&"namein_=Traffic In"&"nameout_=Traffic Out"&"namesum_=Traffic Total"&"parenttags_=hp_2510B-24 hpe"&primarychannel=&priority_=3&sensortype=snmptraffic&stack_=0&"tags_=bandwidthsensor snmptrafficsensor"&tmpid=354&trafficmode_=standinfornoselection 200 "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/144.0.0.0 Safari/537.36 Edg/144.0.0.0"

The server response is Error: PRTG was unable to complete the request. The server responded with the following error: Nothing was selected, no sensors could be created.

I tried to read the documentation and troubleshoot but unfortunately until now no success.

Thanks in advance

Due Dilligance

• It wasn't covered by the wiki, I swear!
• I have tried doing some basic research on this issue but haven't been able to come up with anything. Please help!

[lordmilko]

RawSensorParameters require that you specify every parameter that would normally be specified yourself. It is recommended to instead use DynamicSensorParameters, which include all of the required parameters for you, and then you just need to plug in your sensor targets.

The code would approximately look like the following

//Get the DynamicSensorParameters for creating an snmptraffic sensor
var parameters = client.GetDynamicSensorParameters(1001, "snmptraffic");

//You probably want to filter the targets to just the ones you want
parameters["interfacenumber__check"] = parameters.Targets["interfacenumber__check"];

//Create the sensor(s)
var sensors = client.AddSensor(1001, parameters);

[lossi771]

Hi @lordmilko
thanks for your response and for the wonderful work you are carrying out with this project.

I tried to run your program as is but the system replies with the error message Unhandled exception. System.Collections.Generic.KeyNotFoundException: The given key 'interfacenumber__check' was not present in the dictionary

In my original snippet I tried to use this key because I saw it in the web server logs.

How can I configure the targets for this sensor? Sorry for bothering you but I am a newbie in C# and in this library.

[lordmilko]

Based on other issues that people have reported by understanding is that the field should be called interfacenumber__check; perhaps check what keys are in the Targets property using the debugger?

If you don't have a specific need to use PrtgAPI in C#, it can be easier to use the PowerShell version of this library instead (however the same problem would apply)

[lossi771]

As you may notice from the debugger session, the 'parameters' variable (the DynamicSensorParameters) has the 'Targets' field empty.
However the "snmpTrafficTargets" variable (the result of the client.Targets.GetSensorTargets) lists 43 possible targets.

[lordmilko]

This does not look right to me, I can't see the field where the targets would go. I don't know whether a newer version of PRTG has made some changes that have broken PrtgAPI, or whether there is a configuration issue with your setup. Is your code using the same user account that you would use with the HTTP UI? If so, if you attempt to create an SNMP Traffic sensor on this particular device in the HTTP UI do you get a list of items to choose from? If so, if you then inspect the selectable options using the Chrome Dev Tools (Ctrl+Shift+J) what is the backing name of the field it says they're for? My expectation is the HTML should say interfacenumber__check in there

[lossi771]

Yes, the account is the same and I can see the targets when I try to create an SNMP traffic sensor.
Using the dev tools in Edge I can see this:

[lordmilko]

I'm not sure why the DynamicSensorParameters aren't picking up the targets. PrtgAPI is no longer actively maintained, so all I can do is offer potential workarounds. Since GetSensorTargets does work, you can potentially try and unlock the parameters, and then add the missing interfacenumber__check field and set it to one of the targets returned from GetSensorTargets

[lossi771]

Ok thanks,
based on the request I pasted at the beginning of this conversation
POST /addsensor5.htm aliasavailable=&anti-csrf-token=***&errorintervalsdown_=1&id=77154&inherittriggers=1&"interfacenumber__check=7:7|(007) 7 Traffic|Connected|100 MBit/s|Ethernet|1|7|100000000|3|1|"&interfacenumber_=1&interfacenumber_=1&"interval_=60|60 seconds"&intervalgroup=0&intervalgroup=1&monitorstate_=0&"name=Base Sensor 1"&"namein_=Traffic In"&"nameout_=Traffic Out"&"namesum_=Traffic Total"&"parenttags_=hp_2510B-24 hpe"&primarychannel=&priority_=3&sensortype=snmptraffic&stack_=0&"tags_=bandwidthsensor snmptrafficsensor"&tmpid=354&trafficmode_=standinfornoselection 200 "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/144.0.0.0 Safari/537.36 Edg/144.0.0.0"

how should I unlock and configure the additional parameters?
You help would be much appreciated!

[lordmilko]

See the link in my previous message