I have noticed that with WMI sensors, in this case a WMI disk space sensor, that the sensor display changes according to the lower warning limit and lower error limit defined in the sensor settings. If the value is less than the lower warning limit the sensor display shows a yellow "W" next to the sensor information. If the value is less than the error limit the sensor display will turn red with a "!" If everything is normal the sensor is green.

I have several SNMP sensors and it would be very useful if I could define a "normal" value or range where the sensor display was green and an error value or threshold where the sensor display would change to red or yellow. Can this be done?

The reason I ask this is that often it is very difficult to see at a glance if your SNMP sensors are out of their range. You can't go by the sensor colour because it is always green if the probe could retrieve and value and only turns red if the parent is down or the probe couldn't retrieve a reading.

I have setup notifications to send me an email if the sensor value goes above or below a certain value but it would be great if I could update the sensor display too. That way any user at a glance could see that the sensor is at a warning or error level without having to read the sensor value and interpret it.

I hope I am making sense. Is this possible with SNMP sensors and if so how do you configure this?

Many thanks, Hamish

Article Comments

Edit the channel settings for the sensors in case, and turn on the "Limits" option for the same. You can then define upper and lower warning and error limits, which will also reflect in the gauge graphs of the sensor.


Jan, 2014 - Permalink

Thanks Patrick,

In this case I'm trying to evaluate a text value. The "IF OPER STATUS" channel either returns "up" or "down"

When I edit the channel and enable limits it insists that the error limit (#) must be a number so I can't seem use text there, unless I'm missing another setting to allow this.

Any ideas?

PS: Your previous answer has helped me with most of my SNMP sensors that return integers its just a few that return text.

Thank you!


Jan, 2014 - Permalink

These sensors are SNMP Custom String sensors, then, correct?


Jan, 2014 - Permalink

Its a SNMP Library sensor, I got given an MIB from the manufacturer which I converted and created a library from.


Jan, 2014 - Permalink

Seeing as the counter is returning a string, I'm afraid this isn't possible, seeing as we do not yet support inverse lookups (although there are plans for such a feature in the long-term future). Currently, you would need to use a EXE/Script custom sensor. Sorry.


Jan, 2014 - Permalink