In 12.0-RELEASE, after an upgrade from 11.3-U3.1 results in a "run-away" of the SNMP Agent (python3 /usr/local/bin/snmp-agent.py). That run-away results in a slow-to-respond GUI (sometimes it completely crashes) and also creates significant issues with the console and/or ssh-ing into the server.
Killing the snmp-agent.py process brings back functionality. Disabing the SNMP service in the GUI results in the snmp-agent.py NOT re-starting at boot, which makes the issue go away.
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