Fri May 29, 2020 7:14 pm
What it means is that two or more hosts (in this case routerboards) have the same SNMPv3 engine ID, and net-snmp has mixed up the hosts it has been told to monitor, and is using the engine ID from one router to send requests to another.
In this case you will see one router return SNMPv3 data as normal, and all other routers fail.
To work around the problem, explicitly set the engine-id parameter under /snmp to a unique value (in our case, the name of the router).