MQTT Sparkplug B Driver Guide - Connection State (Status Display Attributes that are Specific to the MQTT Sparkplug B Driver)

Connection State

Associated with: MQTT Sparkplug™ B Broker items

This status attribute indicates the state of the connection between Geo SCADA Expert and the broker that this MQTT Sparkplug B Broker database item represents.

Possible states:

Disconnected—Geo SCADA Expert is not connected to the broker. This might be for any of a number of reasons, such as:
- The MQTT Sparkplug B Broker database item’s configuration is incomplete—for example, the Broker Host Address has not been specified (see Checking for Invalid Configuration).
- The MQTT Sparkplug B Broker database item is not In Service (in which case, the server will typically display an ‘Out of Service’ Quality).
Starting—This indicates that Geo SCADA Expert is currently establishing a connection to the broker. This state is typically fleeting, after which it changes to either the Healthy or Failed state.
Healthy—Geo SCADA Expert has successfully connected to the broker.
Failed—Geo SCADA Expert has not successfully established or maintained a connection to the broker. This can occur, for example, if the broker uses an SSL certificate for communications and that certificate has expired. To ascertain further information about the reason for this state, use the Display Alarms pick action to display the MQTT Sparkplug B Broker database item’s Alarms List, or the Display Events pick action to display the MQTT Sparkplug B Broker database item's Events List.

NOTICE

LOSS of communication

If Geo SCADA Expert is unable to establish a network connection with a device that uses an SSL certificate, check that the certificate is valid, has not expired, and has not been revoked. Perform these checks in addition to those that you would otherwise perform if Geo SCADA Expert is unable to establish a connection with a device.

Failure to follow these instructions can result in loss of communications between Geo SCADA Expert and the network-connected device.

Stopping—This indicates that Geo SCADA Expert is currently disconnecting from the broker. This state is typically fleeting, after which it changes to the Disconnected state.

Also see Connection State Alarm.