<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: Sensor Factory Sensor

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, separated by spaces or commas. You can use tags to group sensors and use tag–filtered views later on. Tags are not case sensitive. We recommend that you use the default value.

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

You can add additional tags to the sensor if you like. Other tags are automatically inherited from objects further up in the device tree. These are visible above as Parent Tags.

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

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).

Channel Definition

Enter a channel definition for the Sensor Factory sensor. Using a specific syntax, you can refer to data from channels of other sensors here. You can also calculate values. Enter one channel definition for each new channel that you want to add to the Sensor Factory sensor.

For more information, see section Define Channels.

Status Handling

Define the behavior of the Sensor Factory sensor if one of the source sensors defined above is in a Down status. In this case, you can set the Sensor Factory sensor either to Down or to Warning status. Choose from:

• Show down status when one or more source sensors are in down status: If at least one source sensor that you use in a channel definition is in a Down status, the Sensor Factory sensor shows a Down status as well until all referred sensors leave this status. While the Sensor Factory sensor is Down, it still shows data of all available channels.
  If a lookup definition or an error limit triggers the Down status of the source sensor, the Sensor Factory does not show a Down status. This is because the Sensor Factory should only show this status if it cannot calculate values.
• Show warning status when one or more source sensors are in down status: If at least one source sensor that you use in a channel definition is in a Down status, the Sensor Factory sensor shows a Warning status until all referred sensors leave the Down status.
  If a lookup definition or an error limit triggers the Down status of the source sensor, the Sensor Factory does not show a Warning status. This is because the Sensor Factory sensor should only show this status if it cannot calculate values.
• Use custom formula: Define the status of the Sensor Factory sensor by adding a status definition in the field below.

Status Definition

This field is only visible if you enable Use custom formula above. Define when the sensor switches to a Down status. You can use the status() function in combination with Boolean operations. For advanced users, it is also possible to calculate a status value.

For more information, see section Define Sensor Status.

If a Source Sensor Has No Data

Choose how this Sensor Factory sensor reacts if a source sensor referred to in the channel definition does not provide any data (for example, because it is paused or does not exist):

• Do not calculate the channels that use the sensor: For defined channels that use one or more sensors that deliver no data, no data is shown.
• Calculate the channels and use zero as source value: If a source sensor that you use in a channel definition does not deliver any data, zero values are filled in instead. The Sensor Factory sensor calculates the channel value and shows it using these zero values.

If a sensor in the channel of a Sensor Factory sensor has no data, the Sensor Factory sensor always shows a Warning status, no matter which of the above options you select.

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.

You 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.
  This 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.

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

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.

Sensors 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.

If you define error limits for a sensor's channels, the sensor immediately shows a Down status. No "wait" option applies.

If a channel uses lookup values, the sensor immediately shows a Down status. No "wait" options apply.

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 settings here. They are active at the same time as the parent objects' settings.

Schedule

Select a schedule from the list. Schedules can be used to monitor for a certain time span (days or hours) every week.

You can create schedules, edit schedules, or pause monitoring for a specific time span. For more information, see section Account Settings—Schedules.

Schedules are generally inherited. New schedules are added to schedules that you already set up, so all schedules are active at the same time.

Maintenance Window

Specify if you want to set up a one-time maintenance window. During a maintenance window, the selected object and all child objects are not monitored. They are in a Paused status instead. Choose between:

• Not set (monitor continuously): No maintenance window is set and monitoring is always active.
• Set up a one-time maintenance window: Pause monitoring within a maintenance window. You can define a time span for a monitoring pause below and change it even for an active maintenance window.

To terminate an active maintenance window before the defined end date, change the time entry in Maintenance Ends to a date in the past.

Maintenance Begins

This field 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 maintenance window.

Maintenance Ends

This field 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 maintenance window.

Dependency Type

Define 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:

• Use parent: Use the dependency type of the parent object.
• Select a sensor: Use the dependency type of the parent object. Additionally, pause the current object if a specific sensor is in a Down status or in a Paused status caused by another dependency.

• Master sensor for parent: Make this sensor the master object for its parent device. The sensor influences the behavior of its parent device: If the sensor is in a Down status, the device is paused. For example, it is a good idea to make a Ping sensor the master object for its parent device to pause monitoring for all other sensors on the device in case the device cannot even be pinged. Additionally, the sensor is paused if the parent group is paused by another dependency.

To test your dependencies, select Simulate Error Status from the context menu of an object that other objects depend on. A few seconds later, all dependent objects are paused. You can check all dependencies under Devices | Dependencies in the main menu bar.

Dependency

This field is only visible if you enable Select a sensor above. Click the Search button and use the object selector to select a sensor on which the current object will depend.

Dependency Delay (Sec.)

This field is only visible if you enable Select a sensor above. Define a time span in seconds for dependency delay.

After the master sensor for this dependency comes back to an Up status, monitoring of the dependent objects is additionally delayed by the defined time span. This can prevent false alarms, for example, after a server restart, by giving systems more time for all services to start up. Enter an integer value.

This setting is not available if you set this sensor to Use parent or to be the Master sensor for parent. In this case, define delays in the parent device settings or in its parent group settings.

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

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.

For more details on access rights, see section Access Rights Management.

Example

You see a definition of two Sensor Factory sensor channels. Both use the channel() function that collects data from the channels of other sensors in your monitoring and displays them:

#1:Local Probe Health
channel(1001,0)
#2:Local Traffic Out[kbit]
channel(1004,1)

The first channel of the Sensor Factory sensor (#1) collects data from the Health channel (ID 0) of the Probe Health sensor (ID 1001) running on the probe device. The second channel (#2) collects data from the Traffic out channel (ID 1) of a traffic sensor (ID 1004) measuring the system's local network card. Both channels are shown together in the Sensor Factory sensor's data tables and graphs.

Example

You see a Sensor Factory sensor channel definition with calculation.

#1:Traffic Total x Minus Traffic Out y
( channel(2001,-1) - channel(1004,1) ) * 2

This full channel definition results in a Sensor Factory sensor that shows a calculation with values from two channels (channel IDs -1 and 1) of two traffic sensors (sensor IDs 2001 and 1004). The returned values are subtracted and then multiplied by two.

Example
 

channel(2001,2)

This function reads the data from channel ID 2 of the source sensor with the ID 2001.
 

#1:Sample
channel(2001,2)

This full channel definition reads the data from channel ID 2 of the source sensor with the ID 2001 and displays it in the first Sensor Factory sensor channel (#1), without any additional calculations.

Examples
 

min(10,5)

This function returns 5, because this is the smaller value out of 10 and 5.
 

min( channel(2001,1),channel(2002,1) )

This function returns the minimum of the values of channel 1 of the source sensor with ID 2001 and channel 1 of the source sensor with ID 2002.

Examples
 

avg(20,10)

This function returns 15: (20+10) / 2 = 15.
 

avg( channel(2001,1),channel(2002,1) )

This function returns the average of channel 1 of the source sensor with ID 2001 and channel 1 of the source sensor with ID 2002.

Examples
 

#1:Usage Traffic In
percent(channel(2001,0),100,kilobit)
#2:Usage Traffic Out
percent(channel(2001,1),100,kilobit)

This full channel definition results in a Sensor Factory sensor that shows two channels of a traffic sensor (sensor ID 2001): Traffic in (channel ID 0) and traffic out (channel ID 1). The Sensor Factory sensor displays the values % of maximum bandwidth (100 kilobit/second).
 

#1:Ping %
percent(channel(2002,0),200)

This full channel definition results in a Sensor Factory sensor that shows the Ping Time channel (channel ID 0) of a Ping sensor (sensor ID 2002). The sensor displays the values as a percentage of 200 ms.

Examples
 

#5:Line at 100ms [ms]
100

This channel definition results in a graph that shows a horizontal line at the value of 100 on the ms scale.
 

#6:Line at 2 Mbit/s [kbit/s]
2000

This channel definition results in a graph that shows a horizontal line at the value of 2000 on the kbit/s scale.
 

#1:Ping Time
channel(2002,0)
#2:Line at 120ms [ms]
120

This full channel definition results in a Sensor Factory sensor that shows the Ping Time channel (channel ID 0) of a Ping sensor (sensor ID 2002). Additionally, the sensor graphs show a horizontal line at 120 ms.

Examples
 

status(2031) AND status(2044)

This changes the Sensor Factory sensor to a Down status if both source sensors, with IDs 2031 and 2044, are Down. Otherwise the Sensor Factory sensor shows an Up status.
 

status(2031) OR status(2044)

This changes the Sensor Factory sensor to a Down status if at least one of the source sensors with ID 2031 or ID 2044 is Down. Otherwise the Sensor Factory sensor shows an Up status.
 

status(2031) AND NOT status(2044)

This changes the Sensor Factory sensor to a Down status if the source sensor with ID 2031 is Down, but the source sensor with ID 2044 is not in a Down status. Otherwise the Sensor Factory sensor shows an Up status.

A status() function with NOT has to be connected with AND or OR if it is combined with other status() functions:
 

status(sensorID) AND NOT status(sensorID)
status(sensorID) OR NOT status(sensorID)

( status(2031) AND status(2044) ) OR status(2051)

This changes the Sensor Factory sensor to a Down status if both the source sensor with ID 2031 and the source sensor with ID 2044 is Down, or if the source sensor with ID 2051 is Down. Otherwise the Sensor Factory sensor shows an Up status.

Example
 

( status(1031) + status(1032) + status(1033) + status(1034) ) >= 20000

This changes the Sensor Factory sensor to a Down status if at least any two of the source sensors with IDs 1031, 1032, 1033, or 1034 are Down. Otherwise the Sensor Factory sensor shows an Up status.