APC NetBotz 250 SNMP monitoring with PRTG

If you want to monitor an APC NetBotz 250 series device for environment monitoring in PRTG, you soon find out that there is no real MIB/OID file respective SNMP reference. APC mentions you can use the regular SNMP network card MIBs, but they only work so far.

The current model of the APC NetBotz 250 comes with an additional wireless temperature monitor, a little device that works with an independent little battery that you will need to exchange every 3 years (estimate).

This sample assumes you will have the following configuration – if not please do a SNMP walk to find out what sensor delivers data where.

  • Wired Sensor 1: Temperature and Humidity probe
  • Wired Sensor 2: Fluid detection probe
  • Wireless Sensor 1: Temperature probe

Add a new SNMP Advanced Sensor to PRTG and name it “RAW data”. This sensor will read the via SNMP from the APC device, we will then further process the data.

  • Channel 1
    • Sensor 1 – Temperature
  • Channel 2
    • Sensor 1 – Humidity
  • Channel 3
    • Sensor 2 – Fluids
  • Channel 4
    • Wireless Sensor 1 – Temperature

After creating this sensor, note the Sensor ID from the URL.

Now add another new PRTG Sensor of the type “Factory Sensor”. This is a special sensor that can process data from one or more other sensors and channels and apply formulas etc.

In the channel definition add the following text

  • 1:Sensor 1 – Temperature[°C]
  • channel(2779,2)/10
  • 2:Sensor 1 – Humidity[%]
  • channel(2779,3)
  • 3:Sensor 2 – Fluid Detection
  • channel(2779,4)
  • 4:Sensor 4 – Wireless Temperature[°C]
  • channel(2779,5)/10

Replace the Sensor ID 2779 with the Sensor ID of your RAW data sensor that you noted earlier, no worries, you can do that as well after you created the probe.

This sensor now shows you more readable data. The temperature from SNMP will be provided in degree Celcius to the tenth, meaning 28.3 C come back raw as 283, the factory sensor corrects this to the 28.3 C.

To get Fahrenheit you need to adjust the channels like this:

  • 1:Sensor 1 – Temperature[°F]
  • ((channel(2779,2)/10)*1.8)+32
  • 2:Sensor 1 – Humidity[%]
  • channel(2779,3)
  • 3:Sensor 2 – Fluid Detection
  • channel(2779,4)
  • 4:Sensor 4 – Wireless Temperature[°F]
  • ((channel(2779,5)/10)*1.8)+32

Eventually it is Celsius times 1.8 plus 32 to get the value in Fahrenheit.

To get alerts, adjust each of the four channel to limits based on their values. For temp and humidity choose ranges that apply to your environment.

As for the Fluid detection, the upper and lower error limit should be 2, as 2 is the only non alert value for this sensor. If fluid is detected, you should get the value 1 back, easy to test with some water and your sensor.