To stop snmpd filling up /var/log/messages with :
"snmpd[3303]: Connection from UDP:"
"snmpd[3303]: Received SNMP packet(s) from UDP:"
use this:
first update net-snmp.x86_64
If Fedora:
/etc/snmp/snmpd.options
OPTIONS="-LS 0-4 d -Lf /dev/null -p /var/run/snmpd.pid -a"
If CentOS:
/etc/sysconfig/snmpd.options
OPTIONS="-LS 0-4 d -Lf /dev/null -p /var/run/snmpd.pid -a"