Net-snmp can be configured to make internal SNMP query and send traps from DISMAN-EVENT-MIB when disk usage exceeds defined threshold.
In order to send traps for the disk usage, add the following lines to snmpd.conf and restart the agent:
# trap target and community
trap2sink localhost public
# authorization for self monitoring
createUser internalMonitoringName SHA mysecretpassword AES
rouser internalMonitoringName
#
iquerySecName internalMonitoringName
# define
# message to send
# OID to monitor
# threshold value
monitor DiskAlmostFull dskPercent > 90
Details can be found on http://www.net-snmp.org/wiki/index.php/TUT:DisMan_Monitoring and in man snmpd.conf
- section about DisMan Event MIB.