Ignition Version: 8.1.28 (b2023060110)
MQTT Version 4.0.13 (b2022092123)
When does this happen ?
As soon as the Transmission Module is enabled
TransmissionClient : Failed to validate the Primary/Critical app is ONLINE - walking to next server
What does this mean ?
This means that the MQTT client associated with the Transmission configuration has the ‘primary host id’ field set. This tells the client to make sure the primary host is online/connected/listening before Transmission will begin sending data. This is a recommended setting.
But, in your case MQTT Engine (or whatever is your primary host) is not online. Either it is not configured with the same primary host ID or it is not properly connected to the MQTT Server. See this: MQTT Engine Primary Host Control - MQTT Modules for Ignition 8.x - Confluence
The problem mentioned above is pertaining to the MQTT Transmission. I dont see a place we can configure Primary Host following the reference MQTT Engine Primary Host Control - MQTT Modules for Ignition 8.x - Confluence
On the Transmission side, the the Primary Host ID is specified in the Set configuration. Search for “Primary Host ID” in this page of the online documentation.
Hi Larry and Wes,
I removed the Primary Host ID from the MQTT Transmission Settings > Sets > Primary Host ID configuration.
I do not see the above error anymore.
Thank you it worked.
I’m glad it worked. I should note, we do generally recommend that people should use primary host ID. MQTT Transmission would have also properly connected if there was a Sparkplug Host Application (such as MQTT Engine) properly connected and publishing it’s Primary Host STATE/online message. This is generally the recommended solution as it prevents MQTT Transmission from publishing data to a Host Application that isn’t even present and listening.
