PRTG Manual: WMI Custom String Sensor
The WMI Custom String sensor performs a custom string query via Windows Management Instrumentation (WMI).
The sensor can also show the retrieved string value in the sensor message.
If the WQL query returns numeric values, use the WMI Custom sensor.
For a detailed list and descriptions of the channels that this sensor can show, see section Channel List.
- Dutch: WMI Aangepaste Tekenreeks
- French: Chaîne personnalisée (WMI)
- German: WMI Text (benutzerdef.)
- Japanese: WMI カスタム文字列
- Portuguese: Sequência de caracteres (customizado) (WMI)
- Russian: Нестандартная строка WMI
- Simplified Chinese: WMI 自定义字符串
- Spanish: Cadena (personalizado) (WMI)
- This sensor has a high performance impact. Stay below 200 WMI sensors per probe. Above this number, consider using multiple remote probes for load balancing.
- This sensor requires WoW64 (Windows 32-bit on Windows 64-bit) for target systems that run Windows Server 2016.
- This sensor requires credentials for Windows systems in the settings of the parent device.
- This sensor supports IPv6.
- Knowledge Base: Why do I have to store SQL sensor queries and custom scripts in files on the probe computer?
- Knowledge Base: How do I create a WMI Custom sensor?
You cannot add this sensor to the hosted probe of a PRTG Hosted Monitor instance. If you want to use this sensor, add it to a remote probe device.
Setting |
Description |
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Sensor Name |
Enter a 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.
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Parent Tags |
The tags that the sensor inherits from its parent device, parent group, and parent probe.
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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.
The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:
|
Priority |
Select a priority for the sensor. This setting determines the position of the sensor in lists. The highest priority is at the top of a list. Choose from the lowest priority ( |
Setting |
Description |
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Namespace |
Enter the WMI namespace for the query. . |
WQL File |
Select a .wql file. The sensor executes it with every scanning interval. The list contains WQL scripts that are available in the \Custom Sensors\WMI WQL scripts subfolder of the PRTG program directory on the probe system. Store your script there. If used on a cluster probe, you must store the file on all cluster nodes.
|
Placeholder <#PH1> |
In your WQL script, you can use up to three placeholders to which you can assign a value in this field. Enter a string for variable <#PH1> or leave the field empty. |
Placeholder <#PH2> |
In your WQL script, you can use up to three placeholders to which you can assign a value in this field. Enter a string for variable <#PH2> or leave the field empty. |
Placeholder <#PH3> |
In your WQL script, you can use up to three placeholders to which you can assign a value in this field. Enter a string for variable <#PH3> or leave the field empty. |
Unit String |
Enter a unit for the data that the sensor receives from your script. This is for display purposes only. The unit is displayed in graphs and tables. Enter a string. |
If Value Changes |
Define what the sensor does when its value changes:
|
Response Must Include (Down Status if Not Included) |
Define the search string that must be part of the data that is received from the WMI object. You can enter a simple string in plain text or a regular expression.
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Response Must Not Include (Down Status if Included) |
Define the search string that must not be part of the data that is received from the WMI object. You can enter a simple string in plain text or a regular expression.
|
Search Method |
Define the method with which you want to provide the search string:
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Maximum String Length |
Define the maximum allowed length of the string that is received from the WMI object. If it is longer than this value, the sensor shows the Down status. Enter an integer or leave the field empty. |
Numeric Value Extraction |
Define if you want to filter out a numeric value from the string received from the WMI object. You can convert this into a float value to use it with channel limits.
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Regular Expression |
This setting is only visible if you select Use a regular expression for extraction above. Enter a regex to identify the numeric value you want to extract from the string returned by the WMI object. You can use capturing groups here.
|
Index of Capturing Group |
This setting is only visible if you select Use a regular expression for extraction above. If your regex uses capturing groups, specify which one captures the number. Enter an integer or leave the field empty. |
Decimal Separator |
This setting is only visible if you select Use a regular expression for extraction above. Define the character for the decimal separator of the number. Enter a string or leave the field empty. |
Thousands Separator |
This setting is only visible if you select Use a regular expression for extraction above. Define the character for the thousands separator of the number. Enter a string or leave the field empty. |
Result Handling |
Define what PRTG does with the sensor result:
Store the last sensor result in the \Logs\sensors subfolder of the PRTG data directory on the probe system. The file names are Result of Sensor [ID].txt and Result of Sensor [ID].Data.txt. This setting is for debugging purposes. PRTG overwrites these files with each scanning interval.
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Setting |
Description |
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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.
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Graph Type |
Define how different channels are shown for this sensor:
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Stack Unit |
This setting is only visible if you select Stack channels on top of each other above. 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. |
By default, all of these settings are inherited from objects that are higher in the hierarchy. We recommend that you change them centrally in the root group settings if necessary. To change a setting for this object only, click under the corresponding setting name to disable the inheritance and to display its options.
For more information, see section Inheritance of Settings.
For more information, see section Root Group Settings, section Scanning Interval.
Schedules, Dependencies, and Maintenance Window
You cannot interrupt the inheritance for schedules, dependencies, and maintenance windows. The corresponding settings from the parent objects are always active. However, you can define additional schedules, dependencies, and maintenance windows. They are active at the same time as the parent objects' settings.
For more information, see section Root Group Settings, section Schedules, Dependencies, and Maintenance Window.
For more information, see section Root Group Settings, section Access Rights.
Number Extraction with Regular Expression
If you want to extract a number in the response string via a regex, note that the index for captures in this sensor is based on 1 (not on 0). Furthermore, capturing groups are not automatically created. The example below illustrates this issue.
Consider the following string as returned by a request for CPU usage:
5 Sec (3.49%), 1 Min (3.555%), 5 Min (3.90%)
Assuming you would like to filter for the number 3.555, this is the percentage in the second parentheses. Enter the following regex in the Regular Expression field:
(\d+\.\d+).*?(\d+\.\d+).*?(\d+\.\d+)
As Index of Capturing Group, enter 3. This extracts the desired number 3.555.
The index must be 3 in this case because the capturing groups here are the following:
- Group 1 contains 3.49%), 1 Min (3.555), 5 Min (3.90
- Group 2 contains 3.49
- Group 3 contains 3.555
- Group 4 contains 3.90
Keep this note about index and capturing groups in mind when using number extraction.
It is not possible to match an empty string with the PRTG regex sensor search.
PRTG supports Perl Compatible Regular Expression (PCRE) regex. For more details, see section Regular Expressions.
Which channels the sensor actually shows might depend on the target device, the available components, and the sensor setup.
Channel |
Description |
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Downtime |
In the channel table on the Overview tab, this channel never shows any values. PRTG uses this channel in graphs and reports to show the amount of time in which the sensor was in the Down status |
Response Time |
The response time
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KNOWLEDGE BASE
Why do I have to store SQL sensor queries and custom scripts in files on the probe computer?
How do I create a WMI Custom sensor?
What security features does PRTG include?
My WMI sensors don't work. What can I do?