PRTG Manual: SNMP Custom Table Sensor
The SNMP Custom Table sensor monitors entries from a table that is provided via the Simple Network Management Protocol (SNMP). You can create one new sensor per table row. For each sensor, you can define up to ten channels. Each channel shows the value of one defined table column.
The SNMP Library sensor automatically creates SNMP Custom Table sensors when the Management Information Base (MIB) file that you import contains tables.
For a detailed list and descriptions of the channels that this sensor can show, see section Channel List.
- Dutch: SNMP Aangepaste Tabel
- French: Table personnalisée (SNMP)
- German: SNMP (Benutzerdef. Tabelle)
- Japanese: SNMP カスタムテーブル
- Portuguese: Tabela customizada (SNMP)
- Russian: Нестандартная таблица SNMP
- Simplified Chinese: SNMP 自定义表
- Spanish: Tabla (personalizado) (SNMP)
- It might not work to query data from a probe device via SNMP (querying localhost, 127.0.0.1, or ::1). Add this device to PRTG with the IP address that it has in your network and create the SNMP sensor on this device instead.
- This sensor supports the IPv6 protocol.
- This sensor has a low performance impact.
- See the Knowledge Base: How do I find out which OID I need for an SNMP Custom sensor?
- See the Knowledge Base: What can I monitor with the SNMP Custom Table sensor?
The Add Sensor dialog appears when you manually add a new sensor to a device. It only shows the settings that are required to create the sensor. You can change nearly all settings on the sensor's Settings tab after creation.
The settings that you select in the Add Sensor dialog are valid for all sensors that you create when you finish the dialog.
Setting |
Description |
---|---|
Table OID |
Enter the object identifier (OID) of the SNMP table that you want to monitor. The OID must directly point to an object that represents an SNMP table. PRTG creates one SNMP Custom Table sensor for each table row that you select.
|
Setting |
Description |
---|---|
Sensor Name |
Enter a meaningful name to identify the sensor. You can use the placeholders [tablename] and [rowidentifier]. PRTG replaces them with the name of the table and the identifying value of the chosen row respectively. You can select the column that provides the row identifier in the Identification Column option below. You can also enter a valid OID that is part of a different SNMP table, for example, [1.3.6.1.2.1.2.2.1.2], to query information that the current table does not contain. PRTG adds the same index as in the original table to the OID. |
Setting |
Description |
---|---|
Table |
The sensor shows you the table that the OID returns. Select the table rows that contain the data that you want to monitor. PRTG creates one sensor for each table row that you select.
|
Identification Column |
Define the identification column for the sensors that you want to create. The sensors use this column to uniquely identify each table row.
|
Channel #2 - #10 |
You can create up to 10 different channels for this sensor. You must define at least one data channel, so you already see all available settings for Channel #1. Additionally, you can define Channel #2 up to Channel #10. To do so, choose between:
|
Value Type |
Select the expected numeric type of the results at the OID:
|
Click the Settings tab of a sensor to change its settings.
Setting |
Description |
---|---|
Sensor Name |
Enter a name to identify the sensor. |
Parent Tags |
Shows tags that the sensor inherits from its parent device, parent group, and parent probe.
|
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 ( |
Usually, a sensor connects to the IP Address/DNS Name of the parent device. See the device settings for details. For some sensors, you can explicitly define the monitoring target in the sensor settings.
SNMP Table
Setting |
Description |
---|---|
Table OID |
Shows the OID of the SNMP table that this sensor monitors.
|
Setting |
Description |
---|---|
Identifier |
This is the value of the column that you selected as the Identification Column during sensor creation. PRTG also displays it in the sensor name to distinguish it from other sensors you created for the same table with other table rows. You can change the identifier if you want to. |
Identification Column |
Shows the table column that you chose as identification column.
|
Channel #x Name |
Enter a name for the channel in which the sensor shows the desired result. Enter a string. |
Channel #x Column |
Select the table column that, together with the table row, points to the value that you want to monitor in this channel. You can choose between the available columns of the table that you monitor. |
Channel #x Value Type |
Shows the value type of the data that this sensor receives in this channel.
|
Channel #x Unit |
Define the unit of the data that this sensor receives in this channel:
|
Channel #x Custom Unit |
This setting is only visible if you select the channel unit Custom above. Define a unit for the channel value. Enter a string. |
Channel #x Lookup |
This setting is only visible if you select the channel unit Lookup above. Select a lookup file that you want to use with this channel. |
Channel #2 - #10 |
Shows if the channel is enabled or disabled.
|
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.
|
Graph Type |
Define how different channels are shown for this sensor:
|
Stack Unit |
This setting 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. |
By default, all of the following 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.
Click to interrupt the inheritance.
Setting |
Description |
---|---|
Scanning Interval |
Select a scanning interval from the dropdown list. The scanning interval determines the amount of time that the sensor waits between two scans. Choose from:
|
If a Sensor Query Fails |
Select the number of scanning intervals that the sensor has time to reach and to check a device again if a sensor query fails. Depending on the option that you select, the sensor can try to reach and to check a device again several times before the sensor shows the 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 the Warning status. Choose from:
|
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.
Setting |
Description |
---|---|
Schedule |
Select a schedule from the list. You can use schedules to monitor during a certain time span (days or hours) every week. Choose from:
|
Maintenance Window |
Select if you want to set up a one-time maintenance window. During a maintenance window, monitoring stops for the selected object and all child objects. They show the Paused status instead. Choose between:
|
Maintenance Begins |
This setting is only visible if you enable Set up a one-time maintenance window above. Use the date time picker to enter the start date and time of the one-time maintenance window. |
Maintenance Ends |
This setting is only visible if you enable Set up a one-time maintenance window above. Use the date time picker to enter the end date and time of the one-time maintenance window. |
Dependency Type |
Select a dependency type. You can use dependencies to pause monitoring for an object depending on the status of a different object. You can choose from:
|
Dependency |
This setting is only visible if you enable Select a sensor above. Click |
Dependency Delay (Sec.) |
This setting is only visible if you select Select a sensor above. Define a time span in seconds for the dependency delay. After the master sensor for this dependency returns to the Up status, PRTG additionally delays the monitoring of the dependent objects by the time span you define. This can prevent false alarms, for example, after a server restart or to give systems more time for all services to start. Enter an integer value.
|
Click to interrupt the inheritance.
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:
|
Which channels the sensor actually shows might depend on the monitored device, the available components, and the sensor setup.
Channel |
Description |
---|---|
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 in percent. |
[Value] |
The returned numeric values in up to ten channels per table row |
Knowledge Base
How do I find out which OID I need for an SNMP Custom sensor?
What can I monitor with the SNMP Custom Table sensor?
What security features does PRTG include?
What SNMP sensors does PRTG offer?
My SNMP sensors don’t work. What can I do?
Can I monitor UPS systems complying with the UPS MIB (RFC-1628) with PRTG?
For more information about sensor settings, see the following sections: