I'm setting up sensors on PRTG to monitor Rx power levels (in dBm) on different transceivers. However, MIB Importer gets integers from them, which after being divided into 100, end up giving me an mW value. After that I have to use an mW to dBm/dBm to mW converter to actually understand the values and set up alarms depending on the transceiver's threshold.

Has anyone had to set up something like this before and got this problem? Is there anything I can do to get the dBm values instead of integers?

Thanks in advance.

Article Comments

What MIB are you using to monitor the power levels and what kit/SFP's are you using?


Mar, 2015 - Permalink

Hello,

Unfortunately, to convert the optical power from mW to dBm is not possible out of the box, sorry. The PRTG sensor factory only supports some basic maths operations and not scientific functions. We do not plan to implement other than the four basic operations to our factory sensors. That means the necessary conversion has to be computed if you are familiar in scripting in your own script.


Mar, 2015 - Permalink

Thanks! I'm a little familiar to scripting, I can research and do that, how do I make it work on PRTG though?


Mar, 2015 - Permalink

Hello,

Either you write a script which requests the data itself and then performs the calculation within the script, or you create a custom sensor which uses the PRTG API to read the raw value of the sensor and then computes its logarithm.


Mar, 2015 - Permalink

Thank you very much for your support.


Mar, 2015 - Permalink

Hello! which method did you use to monitoring the teansceivers?


Jun, 2017 - Permalink

fsolutions,

First of all, I strongly advice you against doing what I did, it's not scalable, nor practical, nor pretty.

The transceivers were installed on optic interfaces on HUAWEI switches across the network. The process was actually cumbersome, I performed snmpwalks on the different versions of devices, and analized the results looking for the oids that would match the Rx power values on the optic interfaces. Then with PRTG's MIB Importer created .oidlib libraries with the oids for the interfaces we needed to monitor. Then after adding the sensors and getting the output in mW, I calculated the values in relation to the dBm conversion and used then to set up warning limits. Due to how inconvenient and time consuming this was, I only did it for really important interfaces, and since I didn't have a whole lot of time by then, I didn't look up into the scripting solution mentioned above, which would have probably been the right way to go.

Best regards,

Adrián


Jul, 2017 - Permalink