PRTG Manual: SNMP Linux Meminfo Sensor

The SNMP Linux Meminfo sensor monitors the memory usage of a Linux/Unix system via the Simple Network Management Protocol (SNMP).

SNMP Linux Meminfo Sensor

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

Sensor in Other Languages

Dutch: SNMP Linux meminfo
French: Linux information mémoire (SNMP)
German: SNMP Linux Speicherinfo
Japanese: SNMP Linux メモリ情報
Portuguese: Meminfo Linux (SNMP)
Russian: Linux Meminfo по SNMP
Simplified Chinese: SNMP Linux 内存信息
Spanish: Meminfo Linux (SNMP)

Remarks

Consider the following remarks and requirements for this sensor:

Remark	Description
IPv6	This sensor supports IPv6.
Performance impact	This sensor has a very low performance impact.
Limits	This sensor has predefined limits for several metrics.
Knowledge Base	Knowledge Base: Monitoring Linux problem - SNMP port not reachable

Basic Sensor Settings

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

memorysensor
snmpmeminfosensor

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

Sensor Display

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. You can set a different primary channel later by clicking 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. You 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.

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.

You can set a different primary channel later by clicking 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.
You 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.

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 under the corresponding setting name to disable the inheritance and to display its options.

For more information, see section Inheritance of Settings.

Channel List

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

Channel	Description
Available Memory	The available memory
Available Memory %	The available memory (%) This channel has default limits: Lower error limit: 5% Lower warning limit: 10%
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 Physical Memory	The free physical memory
Free Physical Memory %	The free physical memory (%) This channel is the primary channel by default. This channel has default limits: Lower error limit: 10% Lower warning limit: 20%
Free Swap Space	The free swap memory
Free Swap Space %	The free swap memory (%) This channel has default limits: Lower error limit: 10% Lower warning limit: 20%
Total Free Memory	The total free memory (physical memory plus swap)
Total Free Memory %	The total free memory (%) (physical memory plus swap) This channel has default limits: Lower error limit: 10% Lower warning limit: 20%