Why can't I see disks when adding the "SNMP Linux Disk Free" sensor in PRTG, despite using the Host Resources MIB in SolarWinds? I want to avoid manually creating sensors for each disk.

In order to monitor SNMP-based Disk Space sensors you require entries similar to the one listed below in the /etc/snmp/snmpd.conf file:

# disk PATH [MIN=DEFDISKMINIMUMSPACE]
#
# PATH:  mount path to the disk in question.
# MIN:  Disks with space below this value will have the Mib's errorFlag set.
#        Default value = DEFDISKMINIMUMSPACE.

# Check the / partition and make sure it contains at least 10 megs.

disk / 10000

Extracted from the snmpd.conf:

Disk Usage Monitoring:

This requires that the agent was built with support for the ucd-snmp/disk module (which is included as part of the default build configuration).

disk PATH [ MINSPACE | MINPERCENT% ]

monitors the disk mounted at PATH for available disk space.


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The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.