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I keep getting this error intermittently on one of my switches when using SNMPv3SNMPERR_UNKNOWN_USER_NAME (SNMP error # -33). I have 3 other switches setup with the same configuration and they are fine. What can I do to troubleshoot this. Are there logs in PRTG that can help?

error-smp#-33 prtg9 snmp-sensor

Created on Jul 20, 2017 11:08:59 PM

4 Replies




Thank you for the KB-Post. There isn't much more that PRTG could log there actually. What you see there is the error message that the target device actually throws, the response to the same SNMP v3 monitoring requests, which most of the time appear to be valid (if the errors only appear intermittently).
How often and how long do you see this issue? Does it help to use a longer interval, and thus reduce the load of SNMP-v3 requests on the targets?

best regards.

Created on Jul 21, 2017 12:17:35 PM by  Torsten Lindner [Paessler Support]



I have got the same problem. Is there any other advice?

Created on Feb 25, 2021 9:45:31 AM



Hi there,

I'm afraid from our side there is nothing new from our side.

Kind regards

Felix Wiesneth - Team Tech Support

Created on Feb 26, 2021 8:30:16 AM by  Felix Wiesneth [Paessler Support]



Don't know which devices you tried to monitor. I had the same issue on my WiFi Controllers .... just don't forget to install/commit pending changes to your switch configuration!

hope that helps anyone.

Created on Jun 8, 2021 4:26:32 PM

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