<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: Similar Sensors

With PRTG, you can detect relationships between different components in your network. For example, you can detect extraordinarily high CPU load that correlates with extraordinarily high traffic at a specific time of a day or week. This can give you a hint to further investigate that part of your network.

What Is Similarity?

The similarity calculation is based on the values that are saved in the sensor history. If measured values change in the same way, the Similar Sensors Detection feature detects it and shows you the sensors for which it found similar data relations. PRTG shows all sensors that reach 85% to 100% similarity.

The analysis of similar sensors is a heuristic calculation that shows interconnections and correlations in your network. The analysis is completely automated. It is based on mathematics and fuzzy logic and optimizes your sensor usage by tracking redundant monitoring of some aspects of your system.

Similar Sensors Detection

You can adjust the depth of the similar sensors detection or turn it off under Setup | System Administration | Monitoring.

You can also enable or disable the similar sensors detection for specific probes, groups, and devices, and specify inheritance in the object's settings, section Advanced Network Analysis.

There are two options to view similar sensors:

• Via the Overview tab of sensors that includes a Similar Sensors section where PRTG lists channels that show similarities to channels of the selected sensor.
• Via Sensors | Simulate Error Status in the main menu bar where you get an overview of all similar sensors.

To edit the list of similar sensors results, use the available filters.

Similar Sensors (Sensor Overview Tab)

Probe, group, device, and sensor pages have tabs that you can use to navigate between different options. For example, you can view your network's status, view monitoring results, or change settings.

On the Overview tab of a sensor, PRTG lists channels that show similarities to channels of the selected sensor. The table is empty if PRTG detects no similarities to the selected sensor.

PRTG shows similar sensors here when channels have 85% similarity or more. The similar sensors detection saves up to 15 entries per sensor.

The Similar Sensors section provides the following information.

PRTG does not show the Similar Sensors section when the analysis is disabled or when you exceed 1,000 sensors and select the Manage automatically based on sensor count (recommended) option as Analysis Depth in the Monitoring settings. In this case, you see the following notice:

Similar Sensors Overview (Sensors Menu)

This page shows the results of the similar sensors detection from the entire monitoring database. PRTG lists all channels with similarities here. Above the table, there are several filter options to display similar sensors as required. Select the object of interest, the degree of similarity, and display back references.

For more information, see also section Working with Table Lists.

The analysis of similar sensors requires sensor data from at least seven days to have enough data for comparison. If not enough data is available, no data is shown on the Similar Sensors Overview or in the Similar Sensors section on a sensor's Overview tab.

PRTG shows similar sensors here when channels have at least 85% similarity. Furthermore, the analysis saves up to 15 entries per sensor.

You can click the column headers to sort the list. The Similar Sensors Overview provides the following information.

PRTG does not show the Similar Sensors Overview item in the main menu bar if you disable the analysis or if you exceed 1,000 sensors and select the Manage automatically based on sensor count (recommended) option as Analysis Depth in the Monitoring settings.

Adjust the Similar Sensors Overview to Your Needs

You can use various filters to adjust the results in the Similar Sensors Overview. Click Show Filters and edit the filters that appear.