PRTG Manual: SNMP Disk Free v2 Sensor

The SNMP Disk Free v2 sensor monitors the free disk space on a logical disk via the Simple Network Management Protocol (SNMP). The sensor uses HOST-RESOURCES-V2-MIB::hrStorageTable.

SNMP Disk Free v2 Sensor

SNMP Disk Free v2 Sensor

i_square_cyanFor a detailed list and descriptions of the channels that this sensor can show, see section Channel List.

Sensor in Other Languages

  • Dutch: SNMP Vrije Schijf Ruimte v2
  • French: Espace disque disponible v2 (SNMP)
  • German: SNMP Datenträgerspeicher v2
  • Japanese: SNMP ディスク空き容量 v2
  • Portuguese: Disco livre (SNMP) v2
  • Russian: SNMP Disk Free v2
  • Simplified Chinese: SNMP 磁盘可用空间版本 2
  • Spanish: Espacio libre en disco (SNMP) v2


Consider the following remarks and requirements for this sensor:




  • This sensor supports IPv6.

Performance impact

  • This sensor has a low performance impact.


  • This sensor has predefined limits for several metrics.


  • It might not work to query data from a probe device via SNMP (querying localhost,, or ::1). Add this device with the IP address that it has in your network and create the sensor on this device instead.

Scanning interval

  • The minimum scanning interval of this sensor is 1 minute.
  • The recommended scanning interval of this sensor is 1 minute.

Multi-platform probe

  • You can add this sensor to a multi-platform probe.

Basic Sensor Settings

Basic Sensor Settings

Basic Sensor Settings

The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:

  • diskfree
  • diskspacesensor
  • snmp
  • snmpdiskfreesensor

i_square_cyanFor more information about basic sensor settings, see section Sensor Settings.

SNMP Disk Free Specific

SNMP Disk Free Specific

SNMP Disk Free Specific




The name of the disk that this sensor monitors.

i_round_redPRTG shows this value for reference purposes only. We strongly recommend that you only change it if the Paessler support team explicitly asks you to do so. Wrong usage can result in incorrect monitoring data.


The type of the disk that this sensor monitors.


The size of the disk that this sensor monitors.

Sensor Display

Sensor Display

Sensor Display



Primary Channel

Select a channel from the list to define it as the primary channel. In the device tree, PRTG displays the last value of the primary channel below the sensor's name. The available options depend on what channels are available for this sensor.

i_round_blueYou can set a different primary channel later by clicking b_channel_primary below a channel gauge on the sensor's Overview tab.

Graph Type

Define how this sensor shows different channels:

  • Show channels independently (default): Show a graph for each channel.
  • Stack channels on top of each other: Stack channels on top of each other to create a multi-channel graph. This generates a graph that visualizes the different components of your total traffic.
    i_round_redYou cannot use this option in combination with manual Vertical Axis Scaling (available in the channel settings).

Stack Unit

This setting is only visible if you select Stack channels on top of each other above.

Select a unit from the list. PRTG stacks all channels with this unit on top of each other. By default, you cannot exclude single channels from stacking if they use the selected unit. However, there is an advanced procedure to do so.

Debug Options

Debug Options

Debug Options



Result Handling

Define what PRTG does with the sensor result:

Do not store the sensor result.

Store the last sensor result in the \Logs\sensors subfolder of the PRTG data directory on the probe system. The file names are Result of Sensor [ID].txt and Result of Sensor [ID].Data.txt. This setting is for debugging purposes. PRTG overwrites these files with each scanning interval.

i_round_blueIn a cluster, PRTG stores the result in the PRTG data directory of the master node.

Inherited Settings

By default, all of these settings are inherited from objects that are higher in the hierarchy. We recommend that you change them centrally in the root group settings if necessary. To change a setting for this object only, click b_inherited_enabled under the corresponding setting name to disable the inheritance and to display its options.

i_square_cyanFor more information, see section Inheritance of Settings.

Channel List

i_round_blueWhich channels the sensor actually shows might depend on the target device, the available components, and the sensor setup.




In the channel table on the Overview tab, this channel never shows any values. PRTG uses this channel in graphs and reports to show the amount of time in which the sensor was in the Down status

Free Space

The free space

Free Space %

The free space (%)

i_round_blueThis channel is the primary channel by default.

i_round_blueThis channel has default limits:

  • Lower error limit: 10%
  • Lower warning limit: 25%

Total Space

The total space


i_square_blueKNOWLEDGE BASE

What security features does PRTG include?

My SNMP sensors don’t work. What can I do?