<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: System Administration—Monitoring

This option is not available in PRTG hosted by Paessler.

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: 1 minute

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: 1 day

We recommend that you do not use intervals below 10 seconds to prevent system overload. Intervals 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.

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.

For 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?

The Unusual Detection feature can set sensors to an 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 here (this means, how big the difference must be to cause an Unusual status). If you disable the unusual detection by setting both settings to Never, sensors never show an Unusual status.

You can enable and disable unusual detection for specific devices, entire 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.

Show Unusual When

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

• Never: Disable unusual detection for weekday average.
• 24h average is <80% or >120% of weekday average: 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: 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): 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: 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: 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 average traffic on a weekday. If you choose the first option, the sensor would show an Unusual status if the average from the day before is below 80 MB or above 120 MB.

Show Unusual When

Define when a sensor shows the Unusual status by comparing the hour of the day. If you enable the detection here, the average of the values that were measured in the hour before is compared to the average of the same hour on the same weekday 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: 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: 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): 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: 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: 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 an Unusual status if the average from the hour before is below 8 MB or above 12 MB.

Record 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 record unusual events
• Record and display unusual events on a sensor's Log tab (default)

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 are analyzed. 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, no data is shown on 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 you have exceeded 1,000 sensors and have chosen the automatic analysis depth option, the Similar Sensors Overview is not shown in the main menu bar.

Analysis Depth

Define the number of channels PRTG analyzes to detect similarities between sensors or turn the analysis off:

• Manage automatically based on sensor count (recommended): The analysis depth depends on the total number of sensors you have configured. PRTG analyzes all channels for up to 500 sensors, and only the primary channels for up to 1,000 sensors. For more than 1,000 sensors, the analysis is turned off. This is the default setting in PRTG on premises.
• Analyze primary channels only: Only the primary channels of sensor are analyzed. Be aware of potentially high CPU load on the PRTG core server system when choosing this setting for more than 1,000 sensors.
• Analyze all channels (higher CPU load): Similarity detection is applied to all channels. Be aware of potentially high CPU load on the PRTG core server system when choosing this setting for more than 500 sensors.
• Turn analysis off: No similarity detection takes place. Choose 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 at a minimum.

This is the default setting in PRTG hosted by Paessler.

The Recommended Sensors Detection feature enables PRTG to analyze devices in your network and suggest sensors that are still 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.

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

This option is not available in PRTG hosted by Paessler.

Detection Engine

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

• Manage automatically based on sensor count (recommended): PRTG runs the detection engine for installations with up to 5,000 sensors by default. If you exceed this threshold, PRTG disables the detection engine for performance reasons. We recommend that you set this option so you do not miss any important monitoring data about your network, without risking running into performance issues.
• Always show recommendations: PRTG always analyzes your devices even if your installation exceeds 5,000 sensors and you never miss any suggestion to complete your monitoring. If you enable this option, keep this setting in mind in case you encounter performance issues.
• Turn recommendations off: PRTG never recommends 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 find the option Recommend Now in device context menus or on Overview tabs anymore.

Run 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. Choose a full hour between 0:00 and 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.

Desired Minimum Uptime

Define which uptime in percent PRTG regards as 100 percent. This setting affects the colors shown next to the sensor icons in reports. Select one of the predefined values between 90 % and 99.999 %.

• Account Settings—My Account
• Account Settings—Notification Templates
• Account Settings—Notification Contacts
• Account Settings—Schedules
• System Administration—User Interface
• System Administration—Monitoring
• System Administration—Notification Delivery
• System Administration—Core & Probes
• System Administration—User Accounts
• System Administration—User Groups
• System Administration—Administrative Tools
• System Administration—Cluster
• PRTG Status—System Status
• PRTG Status—Auto-Update
• PRTG Status—Cluster Status
• PRTG Status—Licensing Status and Settings
• Optional Downloads
• Desktop Notifications
• Support—Help and Support Center
• Support—Contact Support

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

• PRTG Administration Tool on Core Server System
• PRTG Administration Tool on Remote Probe System