<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: Core Health Sensor

The Core Health sensor monitors internal PRTG parameters. It shows the status of the PRTG core server.

The sensor checks various parameters of your PRTG core server that have an impact on the stability of the system:

  • Health: This index value sums up the core state as a value between 100% (healthy) and 0% (failing). Investigate frequent or repeated health values below 100%.
  • Age of Code: This channel shows the time that has passed since the last update of your PRTG core server. Update regularly to get the best security and stability for PRTG, as well as the latest features. We recommend that you use the auto-update to automatically get new versions.
  • CPU Load: This channel shows the CPU load in percent. Extensive CPU load can lead to false, incomplete, and incorrect monitoring results. This value should usually stay below 50%.
  • Handles: This is a counter for the data structures of the operating system. It is responsible for internal resource management. Investigate obviously increasing values that occur repeatedly.
  • Committed Memory: This channel shows the amount of memory committed to the PRTG core server as reported by the memory manager.
  • Configuration Last Saved: This channel shows the time passed since the configuration file was last saved successfully. PRTG saves the configuration every 24 hours. If the configuration cannot be saved, PRTG creates a ticket as soon as the saving process has failed, and warn you via this channel after 26 hours. None of your changes to PRTG can be saved if this happens. In this case, restart your PRTG core server to save the file.
  • Free Page File Memory: This channel shows the amount of free page file memory that is available on the system. Page file memory is aggregated RAM and the size of page file. It is the maximum amount of memory that is available on the system to be used for all running processes. If it gets too low, the system can break down, and at least some applications throw Out of memory errors.
  • Free Physical Memory: This channel shows the amount of free physical memory that is available on the system. This is the RAM that is physically built into the computer. If it gets too low, the system becomes very slow and PRTG no longer works in a useful way. Some sensors might not be displayed correctly and show an Unknown status.
  • Free Virtual Memory: This channel shows the address space on the system that PRTG can access. PRTG cannot use more memory than reported here, which is independent from free page file and physical memory. On a 32-bit operating system, the maximum is 2 GB (3 GB with special settings under Windows). On a 64-bit operating system, it is 4 GB if PRTG runs as a 32-bit version, and unlimited if it runs as a 64-bit version (PRTG core server only). If the free virtual memory gets too low, PRTG throws Out of memory errors or the message not enough storage to process this command. This message is visible in the Core log.
  • Maintenance Days: This channel shows the remaining maintenance days of your PRTG on premises license. Renew your maintenance in time to make sure that you get updates for your PRTG on premises installation. PRTG hosted by Paessler instances show a fixed value here for technical reasons.
  • Threads: This channel shows the number of program parts that are running simultaneously. This number can increase with heavy load. Usually, this number should not exceed 100.
  • Raw Data Buffer: This channel shows how much raw data is temporarily stored on the physical memory during input/output (I/O) operations on the disk. Usually, this value should be 0 (or very low). Investigate increasing values.
Core Health Sensor

Core Health Sensor

Sensor in Other Languages

  • Dutch: Core Status
  • French: État du serveur central
  • German: Serverzustand
  • Japanese: コアの正常性
  • Portuguese: Funcionamento do núcleo
  • Russian: Работоспособность базового сервера
  • Simplified Chinese: 核心健康状况
  • Spanish: Salud del servidor central

Remarks

  • PRTG automatically creates this sensor. You cannot delete it.
  • You can only set up this sensor on a local probe device.
  • You can also find information related to PRTG core server system memory under Setup | PRTG Status. For details, see the Knowledge Base: What do the PRTG core memory parameters mean?

Basic Sensor Settings

Click the Settings tab of a sensor to change its settings.

icon-i-round-blueUsually, a sensor connects to the IP Address or DNS Name of the parent device on which you created the sensor. See the device settings for details. For some sensors, you can explicitly define the monitoring target in the sensor settings. See below for details on available settings.

Setting

Description

Sensor Name

Enter a meaningful name to identify the sensor. By default, PRTG shows this name in the device tree, as well as in alarms, logs, notifications, reports, maps, libraries, and tickets.

Parent Tags

Shows tags that this sensor inherits from its parent device, group, and probe. This setting is shown for your information only and cannot be changed here.

Tags

Enter one or more tags. Confirm each tag with the Spacebar key, a comma, or the Enter key. You can use tags to group objects and use tag-filtered views later on. Tags are not case-sensitive. Tags are automatically inherited. You can add additional tags to the sensor.

icon-i-round-blueIt is not possible to enter tags with a leading plus (+) or minus (-) sign, nor tags with parentheses (()) or angle brackets (<>).

There are default tags that are automatically predefined in a sensor's settings when you add a sensor. See section Default Tags below.

Priority

Select a priority for the sensor. This setting determines where the sensor is placed in sensor lists. A sensor with a top priority is at the top of a list. Choose from one star (low priority) to five stars (top priority).

Default Tags

corehealthsensor

Sensor Display

Setting

Description

Primary Channel

Select a channel from the list to define it as the primary channel. In the device tree, the last value of the primary channel is always displayed below the sensor's name. The available options depend on what channels are available for this sensor.

icon-i-round-blueYou can set a different primary channel later by clicking the pin symbol of a channel on the sensor's Overview tab.

Graph Type

Define how different channels are shown for this sensor:

  • 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.
    icon-i-round-blueThis option cannot be used in combination with manual Vertical Axis Scaling (available in the channel settings).

Stack Unit

This field is only visible if you enable Stack channels on top of each other as Graph Type. Select a unit from the list. All channels with this unit are stacked 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.

Inherited Settings

By default, all of the following settings are inherited from objects that are higher in the hierarchy and should be changed there if necessary. Often, best practice is to change them centrally in the root group settings. For more information, see section Inheritance of Settings. To change a setting for this object only, disable inheritance by clicking the button next to inherit from under the corresponding setting name. You then see the options described below.

Scanning Interval

Click inherited_settings_button to interrupt the inheritance. See section Inheritance of Settings for more information.

Setting

Description

Scanning Interval

Select a scanning interval (seconds, minutes, or hours). The scanning interval determines the amount of time that the sensor waits between two scans. You can change the available intervals in the system administration on PRTG on premises installations.

If a Sensor Query Fails

Define the number of scanning intervals that the sensor has time to reach and check a device again in case a sensor query fails. Depending on the option that you select, the sensor can try to reach and check a device again several times before the sensor shows a Down status. This can avoid false alarms if the monitored device only has temporary issues. For previous scanning intervals with failed requests, the sensor shows a Warning status. Choose from:

  • Set sensor to down immediately: Set the sensor to a Down status immediately after the first failed request.
  • Set sensor to warning for 1 interval, then set to down (recommended): Set the sensor to a Warning status after the first failed request. If the following request also fails, the sensor shows an error.
  • Set sensor to warning for 2 intervals, then set to down: Set the sensor to a Down status only after three consecutively failed requests.
  • Set sensor to warning for 3 intervals, then set to down: Set the sensor to a Down status only after four consecutively failed requests.
  • Set sensor to warning for 4 intervals, then set to down: Set the sensor to a Down status only after five consecutively failed requests.
  • Set sensor to warning for 5 intervals, then set to down: Set the sensor to a Down status only after six consecutively failed requests.

icon-i-round-blueSensors that monitor via Windows Management Instrumentation (WMI) always wait at least one scanning interval before they show a Down status. It is not possible to immediately set a WMI sensor to a Down status, so the first option does not apply to these sensors. All other options can apply.

icon-i-round-blueIf you define error limits for a sensor's channels, the sensor immediately shows a Down status. No "wait" option applies.

icon-i-round-blueIf a channel uses lookup values, the sensor immediately shows a Down status. No "wait" options apply.

Access Rights

Click inherited_settings_button to interrupt the inheritance. See section Inheritance of Settings for more information.

Setting

Description

User Group Access

Define the user groups that have access to the sensor. You see a table with user groups and group access rights. The table contains all user groups in your setup. For each user group, you can choose from the following group access rights:

  • Inherited: Inherit the access rights settings of the parent object.
  • No access: Users in this user group cannot see or edit the sensor. The sensor neither shows up in lists nor in the device tree.
  • Read access: Users in this group can see the sensor and view its monitoring results. They cannot edit any settings.
  • Write access: Users in this group can see the sensor, view its monitoring results, and edit its settings. They cannot edit its access rights settings.
  • Full access: Users in this group can see the sensor, view its monitoring results, edit its settings, and edit its access rights settings.

icon-square-cyanFor more details on access rights, see section Access Rights Management.

Channel Unit Configuration

Click inherited_settings_button to interrupt the inheritance. See section Inheritance of Settings for more information.

Setting

Description

Channel Unit Types

For each type of channel, define the unit in which data is displayed. If defined on probe, group, or device level, these settings can be inherited to all sensors underneath. You can set units for the following channel types (if available):

  • Bandwidth
  • Memory
  • Disk
  • File
  • Custom

icon-i-round-blueCustom channel types can be set on sensor level only.

More

icon-square-blueKNOWLEDGE BASE

What do the PRTG core memory parameters mean?

Edit Channels

To change display settings, spike filtering, and limits, switch to the sensor's Overview tab and click the gear icon of a specific channel. For detailed information, see section Sensor Channel Settings.

Notification Triggers

Click the Notification Triggers tab to change notification triggers. For detailed information, see section Sensor Notification Triggers Settings.

Others

For more general information about settings, see section Object Settings.

Sensor Settings Overview

For information about sensor settings, see the following sections: