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Cisco SG300 SNMP v3 error help



I am trying to monitor ports on a Cisco Small Business SG300 switch with SNMPv3. I receive an error "SNMPERR_AUTHENTICATION_FAILURE (SNMP error # -35)" on some of the ports but not always. Like right now port gigabitethernet24 is giving this error, but it will then report up with kbit/s. A few minutes later it will then say down with the "SNMPERR_AUTHENTICATION_FAILURE (SNMP error # -35)". I have tried changing the delay. I have deleted the snmp user on the Cisco switch and recreated it. I am also trying to use the SNMP system time up sensor, which is experiencing the same behavior as the port sensors.

Any help will be appreciated

Thank you Joe

cisco-switch prtg-13 snmpv3

Created on May 28, 2014 9:39:40 PM

4 Replies




thank you very much for your KB-Post. May I ask, how many SNMPv3-Sensors do you have in total and then on this particular target? Does it help to use longer scanning interval?
Also, which exact version of PRTG are you running?

best regards.

Created on May 30, 2014 12:47:58 PM by  Torsten Lindner [Paessler Support]



HI, we have about 102 total SNMPv3 sensors. The target only has about 16 SNMPv3 sensor. I believe we are on version So far, the last down sensor for the target was on 5/29 about 2 am MST. So, things maybe working normally now.

Created on May 30, 2014 2:57:08 PM



Please update to version 14.2.10 first. We've improved the performance of SNMPv3 sensors a lot since version 13.x.x.

Created on Jun 2, 2014 7:45:55 AM by  Torsten Lindner [Paessler Support]



Hi, found the issue. It ended up being an Double Take sync between to servers that was flooding the network. We will still go ahead with the update to 14.2.10.

Thanks for your help.

Created on Jun 11, 2014 1:51:47 PM

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