GCP Error: The connection broke or was closed by the client

[Jorge_Jeferson_Ferre]

If you are asking a question, please follow this template:

1. My goal is: remove many severity errors on devices log at Google Cloud Log
2. My actions are: performed steps successfully as describe using Mongoose OS + Google IoT Core tutorial.
3. The result I see is: every hour the device disconnect and connect again after 4 or 5 seconds, and generate an error.
4. My expectation & question is: identify the configuration to avoid device error and disconnect/connect process.

As you can see in the image below, every hour the device disconnect and connect again after 4 or 5 seconds. It is generating a bunch of log errors that I would like to prevent. Also, when the device disconnect for 5 seconds, it will lose command if not caught properly.

The error message is “The connection broke or was closed by the client.”
Looking around, I think it may be the heartbeat parameter.

[scaprile]

Google Cloud IoT Core - JWT Refresh

AFAIK it is not possible to refresh the JWT without disconnecting and reconnecting. In fact, the examples in the link seem to actually disconnect MQTT and reconnect. When I tested (mOS 2.17 during 2020), I didn’t see errors but timely disconnect/reconnects every hour (IIRC). Please check if 2.17 behavior is different for you. Some developers have been working on some cloud stuff and that includes GCP (IIRC); but I don’t know whether that includes JWT refresh stuff nor if nor when it will be r…