PRTG Manual: SNMP Custom Sensor

IPv6

This sensor supports IPv6.

Performance impact

This sensor has a very low performance impact.

Localhost

It might not work to query data from a probe device via SNMP (querying localhost, 127.0.0.1, or ::1). Add this device with the IP address that it has in your network and create the sensor on this device instead.

Knowledge Base

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

Channel Name

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

You can change this value later in the channel settings of this sensor.

Unit String

Enter the unit for the values that this sensor returns. Enter a string.

PRTG uses the unit string for display purposes and shows it in graphs, data tables, and gauges.

You can change this value later in the channel settings of this sensor.

OID

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

Most OIDs begin with 1.3.6.1. 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:2.0.0.0.1.

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.

This 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.

You cannot change this value after sensor creation.

Multiplication

If you want to multiply the received data with a certain value, enter the multiplier. Use the default value 1 to not change the received value. Enter an integer.

Division

If you want to divide the received data by a certain value, enter the divisor. Use the default value 1 to not change the received value. Enter an integer.

If Value Changes

Define what the sensor does when its value changes:

• Ignore (default): Do nothing.
• Trigger 'change' notification: Send an internal message that indicates a change.
  In combination with a change trigger, you can use this to trigger a notification if a change occurs.

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.

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

[Value]

The single numeric value (int64) for a specified OID

This channel is the primary channel by default.