PRTG Manual: MQTT Round Trip Sensor

The MQTT Round Trip sensor monitors the availability of a Message Queue Telemetry Transport (MQTT) broker (server), connects to the broker as a publishing and subscribing client, and sends the data packets using a predefined topic.

MQTT Round Trip Sensor

MQTT Round Trip Sensor

i_square_cyanFor a detailed list and descriptions of the channels that this sensor can show, see section Channel List.

Sensor in Other Languages

  • Dutch: MQTT Round Trip
  • French: MQTT Round Trip
  • German: MQTT Round Trip
  • Japanese: MQTT Round Trip
  • Portuguese: MQTT Round Trip
  • Russian: MQTT Round Trip
  • Simplified Chinese: MQTT Round Trip
  • Spanish: MQTT Round Trip

Remarks

  • This sensor requires credentials for MQTT in settings that are higher in the object hierarchy, for example, in the settings of the parent device.
  • This sensor supports the IPv6 protocol.
  • This sensor has a low performance impact.
  • This sensor was converted to a new framework. MQTT Round Trip sensors that were added before PRTG 20.2.59 do not work anymore. We recommend that you pause existing sensors to keep their historic data. To continue monitoring, please add a new MQTT Round Trip sensor.
  • This sensor uses lookups to determine the status values of one or more channels. This means that possible states are defined in a lookup file. You can change the behavior of a channel by editing the lookup file that the channel uses. For details, see section Define Lookups.

Add 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.

Basic Sensor Settings

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

Basic Sensor Settings

Basic Sensor 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.

i_round_blueThis setting is for your information only. You cannot change it.

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.

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

i_round_blueFor performance reasons, it can take some minutes until you can filter for new tags that you added.

The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:

  • roundtrip
  • mqttroundtrip

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 (i_priority_1) to the highest priority (i_priority_5).

i_round_blueUsually, 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.

MQTT Specific

MQTT Specific

MQTT Specific

Setting

Description

Topic

Enter the topic for the round trip. The default is PRTG/roundtrip/%sensorid.

i_round_bluePRTG replaces %sensorid with the sensor's ID.

Connection Settings

Define the connection settings for the connection to the MQTT broker:

  • Use default settings (default): Use the default connection settings.
  • Use custom settings: Use a ClientID that you can specify below.

ClientID

This setting is only visible if you select Use custom settings above. Enter the ClientID for the connection to the MQTT broker. The default is PRTG_%sensorid.

i_round_bluePRTG replaces %sensorid with the sensor's ID. For the subscribing client, PRTG automatically adds _subscriber to the ClientID. For the publishing client, PRTG automatically adds _publisher to the ClientID.

Sensor Display

Sensor Display

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.

i_round_blueYou can set a different primary channel later by clicking b_channel_primary below a channel gauge 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.
    i_round_redYou cannot use this option in combination with manual Vertical Axis Scaling (available in the channel settings).

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.

Debug Options

Debug Options

Debug Options

Setting

Description

Result Handling

Define what PRTG does with the sensor result:

  • Discard result: Do not store the sensor result.
  • Store result: Store the last sensor result in the \Logs\sensors subfolder of the PRTG data directory on the probe system. The file name is Result of Sensor [ID].log. This setting is for debugging purposes. PRTG overwrites this file with each scanning interval.

i_podThis option is not available when the sensor runs on the hosted probe of a PRTG Hosted Monitor instance.

i_round_blueIn a cluster, PRTG stores the result in the PRTG data directory of the master node.

Inherited Settings

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 b_inherited_enabled under the corresponding setting name to disable the inheritance and to display its options.

i_square_cyanFor more information, see section Inheritance of Settings.

Scanning Interval

Scanning Interval

Scanning Interval

i_square_cyanFor more information, see section Root Group Settings, section Scanning Interval.

Schedules, Dependencies, and Maintenance Window

i_round_blueYou 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.

Schedules, Dependencies, and Maintenance Window

Schedules, Dependencies, and Maintenance Window

i_square_cyanFor more information, see section Root Group Settings, section Schedules, Dependencies, and Maintenance Window.

Access Rights

Access Rights

Access Rights

i_square_cyanFor more information, see section Root Group Settings, section Access Rights.

Channel Unit Configuration

i_round_blueWhich channel units are available depends on the sensor type and the available parameters. If no configurable channels are available, this field shows No configurable channels.

Channel Unit Configuration

Channel Unit Configuration

i_square_cyanFor more information, see section Root Group Settings, section Channel Unit Configuration.

Channel List

i_round_blueWhich channels the sensor actually shows might depend on the target 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.

Publisher Connection Time

The time it takes the publisher to connect in milliseconds (msec)

Round Trip Time

The round-trip time (RTT) of the message (after both publisher and subscriber connect) in msec

i_round_blueThis channel is the primary channel by default.

Status

The status of the round trip

  • Up status: Roundtrip Complete
  • Down status: Message Not Received, Message Not Sent, Publisher Could Not Connect, Subscriber Could Not Connect

Subscribe Connection Time

The time it takes the subscriber to connect in msec

More

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