Device is configured with SNMPv3 AuthNoPriv.
Proper User and Groups have been set up.
SNMP Get requests/responses as well as Traps are all send/received properly until the Cisco device reboots.
After the Cisco device reboots, Traps from the device are rejected by the SNMP Manager for unknown reasons.
SNMP Traps are sent by the Cisco device as can be seen in sniffer traces, but the SNMP Engine in the Manager drops/rejects them.
It's presumed that this is due to the snmpEngineBoots has incremented by one and snmpEngineTime has been reset upon reboot, however, it's hard to discern whether this is a Cisco-side problem, SNMP-Manager-side problem or perhaps configuration problem.
Any assistance would be appreciated.
Note: Once the SNMP manager performs a Get request to the rebooted device, traps after that get request are sent are received properly, but if no SNMP Get is performed, Traps are all rejected!
I can't reproduce. We use Net-SNMP 5.4.1 on our FreeBSD server in the lab. I configured a switch to send v3 traps to this server. I generated a config change trap, and verified it showed up in the log. I then reloaded this switch. When it came back up, I sent another trap, and it still showed up in the log.
To configure Net-SNMP, I added a createUser token to /var/net-snmp/snmptrapd.conf, then restarted snmptrapd:
createUser -e ENGINEID USERNAME MD5 PASSWORD
I then edited /usr/local/share/snmp/snmptrapd.conf, and added:
authUser log USERNAME
That's pretty much all I have in that file. Everything works as it should.