the dhcpd configuration option ignore unknown clients doesn’t do what you think it might. Syslog fills up with DHCPINFORM messages with unknown subnet for client address. Must I hack the code for a workaround?

In Ubuntu, Fedora and other systems I’ve seen rsyslog running on, to see the console messages you have to have physical access to the server usually through a KVM or IP-KVM setup. Kernel messages are sent to /dev/console while mail, crit, debug, and others get sent to files. Any of these message can be monitored remotely…

Why does snmpd try to log everything by default in Fedora? If you’re polling every five minutes or so for MRTG or a commercial product like Solarwinds, you might find /var/log/messages filling up with successful connection messages:
Oct 22 04:00:01 ServerName snmpd[2089]:last message repeated 5 times
Oct 22 04:00:01 ServerName snmpd[2089]: …