PRTG Manual: SNMP Linux Disk Free Sensor
The SNMP Linux Disk Free sensor monitors the free space on disks of a Linux/Unix system via the Simple Network Management Protocol (SNMP).
The free space that this sensor returns shows the disk space that is not yet used. Not all of this space might be available for use because a part of this space might be reserved by the system, for example, for redundancy purposes. For more information, see the Knowledge Base: Why do SSH Disk Free and SNMP Linux Disk Free show different values for my target Linux system?
For a detailed list and descriptions of the channels that this sensor can show, see section Channel List.
- Dutch: SNMP Linux vrije schijf ruimte
- French: Linux espace disponible du disque (SNMP)
- German: SNMP Linux-Datenträgerspeicher
- Japanese: SNMP Linux ディスクの空き容量
- Portuguese: Disco livre Linux (SNMP)
- Russian: Свободное пространство диска в Linux по SNMP
- Simplified Chinese: SNMP Linux 磁盘可用空间
- Spanish: Espacio libre en disco Linux (SNMP)
Consider the following remarks and requirements for this sensor:
Remark |
Description |
---|---|
IPv6 |
This sensor supports IPv6. |
Performance impact |
This sensor has a low performance impact. |
Knowledge Base |
The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:
- diskspacesensor
- snmpdiskfreesensor
For more information about basic sensor settings, see section Sensor Settings.
Set Limits Checked for ALL Disks
In this section, you can set limits that are valid for all channels and all drives. With limits, you can define when the sensor shows the Warning or Down status, depending on the data provided by all drives that this sensor monitors. If you want to individually define limits for separate channels, use the limit settings in the channel settings.
All limits that you define here are valid in addition to the limits in the particular channel settings. The limits are valid simultaneously, so the first limit that is breached applies.
Setting |
Description |
---|---|
Percentage Limit Check |
By default, the sensor enables percentage limits with a lower warning limit and a lower error limit. Enable or disable a limit check for the free space in percentage channels of all drives:
|
Upper Error Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings (default) above. Specify an upper limit in percent for the Down status. If the free disk space of one of your drives exceeds this value, the sensor changes to the Down status. Enter an integer or leave the field empty.
|
Upper Warning Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings (default) above. Specify an upper limit in percent for the Warning status. If the free disk space of one of your drives exceeds this value, the sensor changes to the Warning status. Enter an integer or leave the field empty.
|
Lower Warning Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings (default) above. Specify a lower limit in percent for the Warning status. If the free disk space of one of your drives falls below this value, the sensor changes to the Warning status. Enter an integer or leave the field empty.
|
Lower Error Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings (default) above. Specify a lower limit in percent for the Down status. If the free disk space of one of your drives falls below this value, the sensor changes to the Down status. Enter an integer or leave the field empty.
|
Size Limit Check |
Enable or disable a limit check for the free bytes channels of all drives:
|
Upper Error Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings above. Specify an upper limit. Use the same unit as shown by the free bytes channels of this sensor (the default unit is MB). If the free disk space of one of your drives exceeds this value, the sensor changes to the Down status. Enter an integer or leave the field empty.
|
Upper Warning Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings above. Specify an upper limit. Use the same unit as shown by the free bytes channels of this sensor (the default unit is MB). If the free disk space of one of your drives exceeds this value, the sensor changes to the Warning status. Enter an integer or leave the field empty.
|
Lower Warning Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings above. Specify a lower limit. Use the same unit as shown by the free bytes channels of this sensor (the default unit is MB). If the free disk space of one of your drives falls below this value, the sensor changes to the Warning status. Enter an integer or leave the field empty.
|
Lower Error Limit |
This setting is only visible if you select Use the limits of both the sensor and the channel settings above. Specify a lower limit. Use the same unit as shown by the free bytes channels of this sensor (the default unit is MB). If the free disk space of one of your drives falls below this value, the sensor changes to the Down status. Enter an integer or leave the field empty.
|
Alarm on Missing/Removed Disk |
If a monitored disk is removed or not found, the sensor sets the values to zero. Select the alarm approach in this case:
|
Setting |
Description |
---|---|
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.
|
Graph Type |
Define how this sensor shows different channels:
|
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. |
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 under the corresponding setting name to disable the inheritance and to display its options.
For more information, see section Inheritance of Settings.
Which channels the sensor actually shows might depend on the target device, the available components, and the sensor setup.
Channel |
Description |
---|---|
Downtime |
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 Bytes [Partition] |
The free space |
Free INodes [Partition] |
The free index nodes (%) |
Free Space [Partition] |
The free space (%) |
Total |
The free total disk space |
KNOWLEDGE BASE
Why do SSH Disk Free and SNMP Linux Disk Free show different values for my target Linux system?
Monitoring Linux problem - SNMP port not reachable
What security features does PRTG include?
My SNMP sensors don’t work. What can I do?