On the Monitoring tab, you can define global settings for scanning intervals, unusual and similar sensors detection, auto-discovery, and uptime threshold.
This 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.
If 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.
This option is not available in PRTG Hosted Monitor.
Scanning Intervals
Setting
Description
Available Intervals
Define the scanning 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
We 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.
PRTG 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.
Valid 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 Coordinated Universal Time (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.
Your local time might be different from the UTC time.
The Unusual Detection feature sets sensors to the Unusualstatus 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.
You can enable and disable unusual detection for specific devices, groups, and probes in the respective object settings.
Unusual 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
Setting
Description
Show Unusual When
Define when a sensor shows the Unusual status by comparing the day of the week:
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.
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.
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 When
Define when a sensor shows the Unusual status by comparing the hour of the day:
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.
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.
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
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.
Similar 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.
When similar sensors analysis is turned off or if your PRTG installation exceeds 1,000 sensors and you select Manage automatically based on sensor count (default), PRTG does not show the Similar Sensors Overview in the main menu bar.
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:
Manage automatically based on sensor count (default): 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.
This is the default setting in PRTG Network Monitor.
Analyze only primary channels: Only analyze the primary channels. Be 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. Be 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.
This 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.
This option is not available in PRTG Hosted Monitor.
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 (default): 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. We 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. If 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.
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
We 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
The operating methods of the experimental features might change at any time. Do not expect that all functions work properly, or that the experimental features work as expected at all. Be aware that Paessler might remove these features at any time.
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. Beta sensors then become available in the Add Sensor dialog.
If you disable beta sensors, existing beta sensors change to the Unknown status.
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. If you enable PowerShell Security Enhancement, PowerShell scripts that use the write-host cmdlet to provide their output to PRTG do not work anymore. Custom scripts only work if you use the write-output cmdlet. Enabling this feature can also improve the performance of PowerShell sensors.
Disable: Disable PowerShell security enhancement.
Uptime Threshold
Uptime Threshold
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.
90 % - 99.999 %
Save your settings. If you change tabs or use the main menu without saving, all changes to the settings are lost.
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