Send this trap to an SNMP manager — replace <manager> with the IP or hostname of your monitoring server (SNMPv2c):

snmptrap -v2c -c public <manager> '' NETSERVER-MIB::fileSystemFullTrap
snmptrap -v2c -c public <manager> '' 1.3.6.1.4.1.80.0.1

Listen for incoming traps on the manager host (-f keeps it in the foreground, -Lo prints to stdout — useful for testing):

snmptrapd -f -Lo -c /dev/null authCommunity log public

Example snmptrapd log entry:

zoo11-linux.zoo [UDP: [192.168.30.111]:62835->[192.168.30.10]:162]:
  DISMAN-EVENT-MIB::sysUpTimeInstance = Timeticks: (236064115) 27 days, 7:44:01.15
  SNMPv2-MIB::snmpTrapOID.0 = OID: NETSERVER-MIB::fileSystemFullTrap