Quick Start:

    Make sure you have UCD SNMP 3.6.2+ and the Perl SNMP module installed
    Copy snmpvar.mon to your mon.d directory
    Copy snmpvar.def to /etc/mon 
    Copy snmpvar.cf to /etc/mon and edit to match your needs
    Test from mon.d directory with ./snmpvar.monitor -l host1 host2 ...
    Add watch/service to mon.cf, using snmpvar.monitor

Common commandline options:

    --varconf=/path/to/snmpvar.def if neither /etc/mon nor /usr/lib/mon/etc
    --config=/path/to/snmpvar.cf if neither /etc/mon nor /usr/lib/mon/etc
    --community=your_SNMP_read_community if not 'public'

Basic Troubleshooting:

    use snmpvar.monitor --list option to see variable values
    use snmpwalk your_hostname public .1 | less to verify SNMP agent