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SNMP Library sensor fails to install



I'm having a heck of a time trying to get an SNMP Library sensor to install for a specific device. I've used the Paessler SNMP Tester (version 20.2.4) and adjusted the device's SNMP and security settings to allow the tester to pull basic data like Device Uptime as well as walking through part of the OID hierarchy from the device's MIB/OIDLIB file, but when I attempt to install the Library sensor using the PRTG Desktop and selecting the OIDLIB file created from the Paessler MIB Importer (version 3.5.8) the sensor creation fails with "Error connecting device. Check IP, Port, Community!"

Not sure how to further troubleshoot this. One thing I notice is there's nowhere to input the device's community string, so I set it to generic "public" on the device with READ ONLY rights and use the public community name when using the tester.

Thanks for any suggestions.


oidlib snmp-library snmp-sensor

Created on Jun 26, 2020 6:28:17 PM

2 Replies

Accepted Answer



Hello Seáinín,

1) Did you run the SNMP tester on the Server where PRTG is installed? The SNMP Tester needs to work on the system of your PRTG probe.
2) Are you able to add other SNMP sensors to this device (for example SNMP Uptime Sensor)
3) Your SNMP settings (community string) need to be configured correctly within PRTG in the settings of the corresponding device

Kind Regards,
Timo Dambach
Paessler Tech Support

Created on Jun 29, 2020 6:39:34 AM by  Timo Dambach [Paessler Support]



Thanks. The trick were the SNMP settings on the device itself. I was able to run the SNMP Tester successfully from the PRTG server and I was able to add other SNMP types of sensors to the device, just not the SNMP Library sensor. Once I updated the SNMP settings on the device to match what I was using on the target, the library sensor created without issue.



Created on Jun 29, 2020 1:23:06 PM

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