When built without --disable-snmptrapd-subagent configure argument snmptrapd neither doesn't log traps, nor handles them. Furthermore, it starts way too long (several minutes). When build with this argument, it behavies just fine. Just like it's described here: https://sourceforge.net/p/net-snmp/mailman/message/22074123/ I got this on a recent ports tree (yesterday's actually). I have several FreeBSd machines with old net-snmp (5.7.2) where this behaviour isn't encountered. However, it's reproducible on newer versions. I think this should be implemented, if not mandatory, then as an option definitely.
A commit references this bug: Author: zi Date: Tue May 31 13:45:31 UTC 2016 New revision: 416198 URL: https://svnweb.freebsd.org/changeset/ports/416198 Log: - Add OPTION to pass --disable-snmptrapd-subagent to configure PR: 209885 Submitted by: emz@norma.perm.ru Changes: head/net-mgmt/net-snmp/Makefile
OPTION added.