<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: Monitoring

On the Monitoring tab, you can define global settings for scanning intervals, unusual and similar sensors detection, auto-discovery, and uptime threshold.

i_round_blueThis documentation refers to an administrator that accesses the PRTG web interface on a master node. Other user accounts, interfaces, or failover nodes might not have all of the options in the way described here. In a cluster, note that failover nodes are read-only by default.

i_podIf 15 minutes (900) seconds have passed since your last credential-based login and you open a setup page from a different setup page, PRTG asks you to enter your credentials again for security reasons. A dialog box appears. Enter your Login Name and Password and click OK to continue.

In this section:

Scanning Intervals

i_podThis option is not available in PRTG Hosted Monitor.

Scanning Intervals

Scanning Intervals

Setting

Description

Available Intervals

Define the intervals available in the dropdown list of every object's settings. In the text field, enter one value in each line. Use s, m, h, and d to define seconds, minutes, hours, and days. By default, the following scanning intervals are available:

    • 30s: 30 seconds
    • 1m: 60 seconds
    • 5m: 5 minutes
    • 10m: 10 minutes
    • 15m: 15 minutes
    • 30m: 30 minutes
    • 1h: 1 hour
    • 4h: 4 hours
    • 6h: 6 hours
    • 12h: 12 hours
    • 1d: 24 hours

i_round_redWe recommend that you do not use scanning intervals that are below 10 seconds to prevent system overload. Scanning intervals that are below 10 seconds are not officially supported. The maximum supported scanning interval is 10 days.

i_round_bluePRTG might convert values that you enter to a more readable equivalent of the values. For example, if you enter 24h (24 hours), PRTG displays this as 1d (one day) in the dropdown list in the object settings.

i_round_blueValid values are positive integers followed by s, m, h, and d. You can also define specific points in time to indicate when PRTG executes scanning actions. Enter up to 50 concrete <%P_UTC%> points in time according to the formula @ UTC hh:mm , hh:mm. You do not need to use a space before and/or after the comma. However, PRTG always saves the entries with a space both before and after the comma.

i_round_redYour local time might be different from the UTC time.

i_square_cyanFor more information on how to set specific points in time as a scanning time for sensors, see the Knowledge Base: Can I set a sensor to run at a specific time?

Unusual Detection

The Unusual Detection feature sets sensors to the Unusual status when there are values that are not typical for the time span in which they are measured. PRTG compares the current average values to the historic monitoring results for this purpose. If the current values show a big difference to the values that are normally retrieved by a sensor, this sensor indicates this with the Unusual status.

You can define the granularity of the unusual detection, that is, how big the difference must be to cause the Unusual status. If you disable the unusual detection by setting both settings to Never, sensors never show the Unusual status.

i_round_blueYou can enable and disable unusual detection for specific devices, groups, and probes in the respective object settings.

i_round_blueUnusual detection requires sensor data from at least four weeks (28 to 34 days) to have enough data available for comparison. If less data is available, PRTG cannot calculate the Unusual status.

Unusual Detection

Unusual Detection

Setting

Description

Show Unusual Status When

Define when a sensor shows the Unusual status by comparing the day of the week. If you enable this unusual detection, the average of the values that were measured on the day before is compared to the average of the same day of the week in previous weeks. Choose from:

  • Never: Disable unusual detection for weekday average.
  • 24h average is <80% or >120% of weekday average: Show the Unusual status when the average of the values measured on the day before is either lower than 80% or higher than 120% than usual on the same weekday.
  • 24h average is <50% or >200% of weekday average: Show the Unusual status when the average of the values measured on the day before is either lower than 50% or higher than 200% than usual on the same weekday.
  • 24h average is <20% or >500% of weekday average (recommended): Show the Unusual status when the average of the values measured on the day before is either lower than 20% or higher than 500% than usual on the same weekday.
  • 24h average is <10% or >1,000% of weekday average: Show the Unusual status when the average of the values measured on the day before is either lower than 10% or higher than 1,000% than usual on the same weekday.
  • 24h average is <1% or >10,000% of weekday average: Show the Unusual status when the average of the values measured on the day before is either lower than 1% or higher than 10,000% than usual on the same weekday.

For example, consider a traffic sensor that usually measures 100 MB of average traffic on a weekday. If you choose the first option, the sensor shows the Unusual status if the average from the day before is lower than 80 MB or higher than 120 MB.

Show Unusual Status When

Define when a sensor shows the Unusual status by comparing the hour of the day. If you enable this unusual detection, the average of the values that were measured in the hour before is compared to the average of the same hour on the same day of the week in previous weeks. Choose from:

  • Never: Disable unusual detection for hour-of-day average.
  • Hourly average is <80% or >120% of hour-of-day average: Show the Unusual status when the average of the values measured in the hour before is either lower than 80% or higher than 120% than usual in this hour of this weekday.
  • Hourly average is <50% or >200% of hour-of-day average: Show the Unusual status when the average of the values measured in the hour before is either lower than 50% or higher than 200% than usual in this hour of this weekday.
  • Hourly average is <20% or >500% of hour-of-day average (recommended): Show the Unusual status when the average of the values measured in the hour before is either lower than 20% or higher than 500% than usual in this hour of this weekday.
  • Hourly average is <10% or >1,000% of hour-of-day average: Show the Unusual status when the average of the values measured in the hour before is either lower than 10% or higher than 1,000% than usual in this hour of this weekday.
  • Hourly average is <1% or >10,000% of hour-of-day average: Show the Unusual status when the average of the values measured in the hour before is either lower than 1% or higher than 10,000% than usual in this hour of this weekday.

Consider a traffic sensor that usually measures 10 MB average traffic within an hour. If you choose the first option, the sensor would show the Unusual status if the average from the hour before is below 8 MB or above 12 MB.

Log Unusual Events

Define if you also want to record unusual events and display them on the Log tab of a sensor that shows the Unusual status:

  • Do not log unusual events
  • Log and display unusual events on a sensor's Log tab (default)

Similar Sensors Detection

The Similar Sensors Detection feature enables PRTG to analyze sensor data for similarities. The detection runs in the background with low priority. The recommended setting for the analysis depth is to let PRTG automatically decide how many channels it analyzes. However, you can also override this setting.

i_round_blueSimilar sensors analysis requires sensor data from at least seven days to have enough data for comparison. If not enough data is available, PRTG does not display data in the Similar Sensors Overview or in the Similar Sensors section on a sensor's Overview tab. For more information, see section Similar Sensors.

i_round_blueWhen similar sensors analysis is turned off or if your PRTG installation exceeds 1,000 sensors and you select Manage automatically based on sensor count (recommended), PRTG does not show the Similar Sensors Overview in the main menu bar.

Similar Sensors Detection

Similar Sensors Detection

Setting

Description

Analysis Depth

Define the number of channels that PRTG analyzes to detect similarities between sensors, or disable the analysis. The analysis depth depends on the total number of sensors you have. Choose from:

  • Manage automatically based on sensor count (recommended): Analyze all channels for up to 500 sensors and only the primary channels for up to 1,000 sensors. For more than 1,000 sensors, PRTG disables the analysis.
     

i_popThis is the default setting in PRTG on premises.

  • Analyze only primary channels: Only analyze the primary channels.
    i_round_blueBe aware of potentially high CPU load on the PRTG core server system if your PRTG installation has more than 1,000 sensors.
  • Analyze all channels (higher CPU load): Analyze all channels.
    i_round_blueBe aware of potentially high CPU load on the PRTG core server system if your PRTG installation has more than 500 sensors.
  • Disable detection of similar sensors: Do not detect similarities. Select this option if you are not interested in the analysis results or if you want to keep the CPU load on the PRTG core server system to a minimum.
     

i_podThis is the default setting in PRTG Hosted Monitor.

Recommended Sensors Detection

The Recommended Sensors Detection feature enables PRTG to analyze devices in your network and to suggest sensors that are missing for a complete monitoring setup. The analysis runs with low priority in the background when you add a new device, when the last analysis was executed more than 30 days ago, or when you manually start it.

i_square_cyanSee section Recommended Sensors for more information, for example, on SNMP settings, on the results you get and on how to add the suggested sensors.

i_podThis option is not available in PRTG Hosted Monitor.

Recommended Sensors Detection

Recommended Sensors Detection

Setting

Description

Detection Handling

Define if you want PRTG to analyze your devices and to recommend useful sensors:

  • Manage automatically based on sensor count (recommended): Run the detection engine for installations with up to 5,000 sensors. If you exceed this threshold, PRTG disables the detection engine for performance reasons.
    i_round_blueWe recommend that you select this option so that you do not miss any important monitoring data about your network, without risking running into performance issues.
  • Always show recommended sensors: Always analyze your devices even if your installation exceeds 5,000 sensors and if you never want to miss any suggestion to complete your monitoring.
    i_round_blueIf you select this option, keep it in mind in case you encounter performance issues.
  • Disable sensor recommendations: Never recommend sensors. Select this option if you have performance issues with PRTG or if you do not want to see this information on devices' Overview tabs. Moreover, you do not see the option Recommend Now in device context menus or on Overview tabs anymore.

Auto-Discovery

Auto-Discovery

Auto-Discovery

Setting

Description

Run Auto-Discovery At

Define the time when PRTG automatically runs an auto-discovery in your network if you configured a daily or weekly Schedule in the auto-discovery group settings. Select a full hour.

  • 00:00 - 23:00

i_round_blueWe recommend that you choose a time when there is little user activity in your network because auto-discoveries can produce a certain amount of load.

Experimental Features

Experimental Features

Experimental Features

Setting

Description

Beta Sensors

Select if you want to enable or disable sensors in beta status:

  • Disable (default): Disable sensors in beta status.
  • Enable: Enable sensors in beta status.
    i_round_blueBeta sensors then become available in the Add Sensor dialog.

i_round_blueIf you disable beta sensors, existing beta sensors change to the Unknown status.

i_round_redThe operating methods and the available settings of sensors in beta status can change at any time. Do not expect that all functions work properly, or that this sensor works as expected at all. Be aware that sensors in beta status can be removed from PRTG at any time.

PowerShell Security Enhancement

Select if you want to improve PowerShell security by hiding command-line parameters in the process explorer and the event log:

  • Enable (default): Enable PowerShell security enhancement.
    i_round_blueEnabling this feature can also improve the performance of PowerShell sensors.
  • Disable: Disable PowerShell security enhancement.

i_round_redThe operating methods of this feature can change at any time. Do not expect that all functions work properly, or that this feature works as expected at all. Be aware that this feature can be removed from PRTG at any time.

Uptime Threshold

Minimum Uptime

Minimum Uptime

Setting

Description

Minimum Uptime

Define which uptime in percent PRTG regards as 100 percent. This setting affects the colors that you see next to sensor icons in reports. Choose from:

  • 90 % - 99.999 %

i_round_redSave your settings. If you change tabs or use the main menu without saving, all changes to the settings are lost.

More

i_square_blueKNOWLEDGE BASE

How can I speed up PRTGā€”especially for large installations?

How and where does PRTG store its data?

Can I set a sensor to run at a specific time?

Setup

Others

There are some settings that you must make in the PRTG Administration Tool. For more details, see the sections: