<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: SNMP Custom Advanced Sensor

The SNMP Custom Advanced sensor monitors numeric values returned for object identifiers (OID) via the Simple Network Management Protocol (SNMP).

i_round_blueThe SNMP Library sensor automatically creates SNMP Custom Advanced sensors when the Management Information Base (MIB) file that you import contains single values.

SNMP Custom Advanced Sensor

SNMP Custom Advanced 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 Aanpasbaar Geavanceerd
  • French: SNMP personnalisé avancé
  • German: SNMP (Benutzerdef. erweitert)
  • Japanese: SNMP カスタムアドバンスト
  • Portuguese: SNMP (customizado / avançado)
  • Russian: Дополнительные пользовательские параметры SNMP
  • Simplified Chinese: SNMP 自定义高级
  • Spanish: SNMP (personalizado / avanzado)


  • This sensor supports IPv6.
  • This sensor has a low performance impact.
  • This sensor can use lookups. Select Lookup as Channel #x Unit and define the lookup file in Channel #x Lookup.
  • 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.

Basic Sensor Settings

Basic Sensor Settings

Basic Sensor Settings



Sensor Name

Enter a name to identify the sensor. By default, PRTG shows this name in the device tree, as well as in alarms, logs, notifications, reports, maps, libraries, and tickets.

i_round_blueIf the name contains angle brackets (<>), PRTG replaces them with braces ({}) for security reasons. For more information, see the Knowledge Base: What security features does PRTG include?

Parent Tags

The tags that the sensor inherits from its parent device, parent group, and parent probe.

i_round_blueThis setting is for your information only. You cannot change it.


Enter one or more tags. Confirm each tag with the Spacebar key, a comma, or the Enter key. You can use tags to group objects and use tag-filtered views later on. Tags are not case-sensitive. Tags are automatically inherited.

i_round_blueIt is not possible to enter tags with a leading plus (+) or minus (-) sign, nor tags with parentheses (()) or angle brackets (<>).

i_round_blueFor performance reasons, it can take some minutes until you can filter for new tags that you added.

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

  • snmpcustomsensor
  • snmpcustomadvanced


Select a priority for the sensor. This setting determines the position of the sensor in lists. The highest priority is at the top of a list. Choose from the lowest priority (i_priority_1) to the highest priority (i_priority_5).

OID Settings

OID Settings

OID Settings



Channel #x Name

Enter a name for the channel in which the sensor shows the results at the OID. Enter a string.

Channel #x OID

Enter the OID of the SNMP object from which you want to receive numeric data.

i_round_blueMost OIDs begin with However, OIDs that start with 1.0, or 1.1, or 1.2 are also allowed. If you want to entirely disable the validation of your entry, add the string norfccheck: to the beginning of the OID, for example, norfccheck:

Channel #x Value Type

Select the expected numeric type of the results at the OID:

  • Absolute (unsigned integer): Integers without an operational sign, such as 10 or 120.
  • Absolute (signed integer): Integers with an operational sign, such as -12 or 120.
  • Absolute (float): Float values, such as -5.80 or 8.23.
  • Delta (counter): Counter values. PRTG calculates the difference between the last and the current value. PRTG additionally divides the delta value by a time period to indicate a speed value.

i_round_redThis mode only works if the difference between the last and the current value is positive and increases with each scanning interval. This mode does not support negative values and decreasing values.

i_round_redAbsolute (float) and Delta (counter) are not compatible with the unit Lookup.

i_round_blueYou cannot change this value after sensor creation.

Channel #x Unit

Define the unit of the numeric data that this sensor receives from the OID:

  • BytesBandwidth
  • BytesMemory
  • BytesDisk
  • Temperature
  • Percent
  • TimeResponse
  • TimeSeconds
  • TimeHours
  • Count
  • CPU
  • BytesFile
  • SpeedDisk
  • SpeedNet
  • Custom
  • Lookup

i_square_cyanFor more information about the available units, see section Custom Sensors.

i_round_blueTo use lookups with this channel, select Lookup and define the lookup file in Channel #x Lookup. Do not use Custom if you use lookups with this sensor.

i_round_redYou cannot use the unit Lookup if you select the value type Delta (counter) or Absolute (float). You are not able to create the sensor in this case.

Channel #x Custom Unit

This setting is only visible if you select Custom above.

Define a unit for the channel value. Enter a string.

Channel #x Lookup

This setting is only visible if you select Lookup above.

Select a lookup file that you want to use with this channel.

Channel #2 - #10

You can define up to 10 channels. You must define at least one channel, so you see all available settings for Channel #1. Specify how to handle all other possible channels:

  • Disable: Do not create this channel.
  • Enable: Create this channel.

i_round_blueIt is not possible to enable or disable channels after sensor creation.

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, the last value of the primary channel is always displayed 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 different channels are shown for this sensor:

  • 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. All channels with this unit are stacked 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 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.

Scanning Interval

Scanning Interval

Scanning Interval

i_square_cyanFor more information, see section Root Group Settings, section Scanning Interval.

Schedules, Dependencies, and Maintenance Window

i_round_blueYou cannot interrupt the inheritance for schedules, dependencies, and maintenance windows. The corresponding settings from the parent objects are always active. However, you can define additional schedules, dependencies, and maintenance windows. They are active at the same time as the parent objects' settings.

Schedules, Dependencies, and Maintenance Window

Schedules, Dependencies, and Maintenance Window

i_square_cyanFor more information, see section Root Group Settings, section Schedules, Dependencies, and Maintenance Window.

Access Rights

Access Rights

Access Rights

i_square_cyanFor more information, see section Root Group Settings, section Access Rights.

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


The numeric value for a specified OID (up to 10 OIDs are possible) that refers to a specific SNMP device


i_square_blueKNOWLEDGE BASE

How do I find out which OID I need for an SNMP Custom sensor?

What security features does PRTG include?

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