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SNMP not working



I am trying to monitor our UPS with PRTG but I get an 2003 error. I have tested with SNMP tester and get the same issue. But, if I try with another SMNP requester ( Ireasoning Mib Browser), it works fine. I am in snmp v1.

I have no idea where to investiguate.

Thanks for you help.....

snmp-custom-sensor snmp-error#2003 snmp-tester

Created on Mar 9, 2020 2:54:51 PM

2 Replies




First, please make sure you do the test on the Windows host on which the (Local-/Remote-) Probe is installed. Also please double check your credentials and settings.

If this does not help I ask you to do a wireshark trace of the working test with the iReasoning MIB Browser and a trace of the non working test with our SNMP Tester.

After that, please open a ticket with Tech Support and attach the trace-file and also the result files and screenshots of both testers.

Please don't post any traces here, as SNMPv1 and SNMPv2c are completely unencrypted.

Kind regards,
Matthias Kupfer Team Tech Support

Created on Mar 10, 2020 8:53:33 AM by  Matthias Kupfer [Paessler Support]




I have compared the wireshark traces and discovered a community name issue. It works now.


Created on Mar 10, 2020 10:50:36 AM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.