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Auto-Naming sensors with MIB Importer V3.4.7



I've been working on a custom SNMP library for Ruskus ZoneDirectors and have it mostly where I want it. The issue I'm having now as I finish up is the ability to feed in the results from a UID look-up into the Group/Name fields during discovery.

I have OID's using the exact same Group name "AP: #[]" but during discovery, it seems some will walk through the list of results , so each sensor gets the right name of the access point its related to, while others will just use the very first value returned, so all my sensors are looking at different AP's, but all of their names are the same.

I also found that sometimes it doesn't return a value at all. I would put in "AP: #[]" and it would just use that literally as the name, not try to resolve it to an actual string.

My only guess so far is that the different sensors seem to be under different Agent groups and maybe that is affecting it? Though one of the sensors that wouldn't get a string at all was under the Agent group that had the OID in it, while others that are working are referencing a value in a different Agent group.

Any help to get this working would be appreciated as renaming sensors after each discovery can cost a huge amount of time.

Best regards,


auto-discovery mib-importer name

Created on Oct 17, 2013 5:02:43 PM

3 Replies



Jonathan, I'm not quite understanding what you are trying to do here. In PRTG during Auto-Discovery, PRTG will use the IP of the device to lookup the DNS name which is what it will use for the name, the OID isn't converted. With certain types of SNMP sensors, PRTG can also do a lookup in the OID tree for the name but this is for interface sensors and the like. Can you perhaps clarify what you are trying to do here maybe with some screenshots?

Created on Oct 21, 2013 9:43:14 AM by  Greg Campion [Paessler Support]



Hello Greg,

PRTG will actually convert OID calls to names during discovery, your own sensors do this currently for many things. What I've found though is a bug in how it pulls out the names from the OID's by not reseting its walk through index each time it does a discovery for a new sensor. I've made two pictures to show what I mean.

Picture 1

In the above picture which I hope loads, you'll see my settings for MibImporter. What you'll see is that I have different Agent groups (based on the .mib files I imported), but similar Group names: AP: #[] . When I do the discovery task, PRTG is pretty smart and will do an SNMP lookup on the device to change #[] into the value returned. In this case its the name of the Access Point that the sensor is apart of.

This works perfectly fine for the first run through of that SNMP OID index, it goes through AP 0, 1, 2, 3, 4 etc like it should for each sensor. What happens though is that the next time I call for this value, it doesn't start over from 0, instead its stuck on the last index value. As you'll see in the next picture what I get when I do a discovery.

Broken Discovery

The first run through with the group for both the 2.4GHz and 5Ghz radio statuses works flawlessly, each AP's name is correct for both sensors since its going through a loop like so: Group name = AP name Find Radio Status for 2.4Ghz = OK Find Radio Status for 5Ghz = OK Incress index of Group Name Increase index of Radio Status for both 2.4Ghz and 5Ghz.

Whats not happening at the end of the group discovery is the Index values being reset to 0. So you get what you see in my second picture with all calls to the AP name OID being the last index value. This affects any repeated call to an OID from a SNMP Library. I could split the library into chunks but that defeats the purpose of making it a simple discovery task for other users who are't very knowledgeable about PRTG's quirks.

Please let me know if I can provide any more info about this problem.



Created on Oct 21, 2013 5:43:58 PM

Last change on Oct 22, 2013 1:58:31 PM by  Greg Campion [Paessler Support]



Could you please send over the MIB files to the address [email protected] so we can take a look at them and see if we can find if there is a bug?

Created on Oct 22, 2013 1:59:15 PM by  Greg Campion [Paessler Support]

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