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I'm getting "SNMPERR_BAD_SENDTO (SNMP error # -12)" when trying to add a snmp sensor to localhost



I'm running a remote probe locally on a device that I want to monitor using SNMP. Everytime I try to add a sensor I get the error "SNMPERR_BAD_SENDTO (SNMP error # -12)". What can I do to make it work?

localhost snmp snmp-error-#--12 snmperr-bad-sendto

Created on Nov 18, 2013 2:58:00 PM by  Johannes Herrmann [Paessler Support] (1,360) 2 2

4 Replies



Please try to add a new device that is using the "external ip address" of the device. We've encountered some problems that could be fixed by avoiding "localhost", "" and "::1" with SNMP.

Created on Nov 18, 2013 2:59:43 PM by  Johannes Herrmann [Paessler Support] (1,360) 2 2



I have an identical problem, but using the "external" IP address has not corrected the issue for me. Is there anything else I could try please?

Created on Jan 21, 2015 11:29:59 AM




Does your device use multiple NICs? If so, please try to use another address. Furthermore you can use the SNMP Tester and scan the device for e.g. the uptime. Which result do you get using the tester?

Best regards

Created on Jan 22, 2015 3:45:22 PM by  Felix Saure [Paessler Support]



I received the same error message when I created the SNMP Memory Sensor. Fixed it by changing the probe's IP address to auto as it had 2.

Created on Jun 3, 2020 5:57:19 PM

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