How to retrieve the status of my mqtt

[Trying_to_learn]

I am only offering suggestions.

As the build seems to be mostly remote machines, it makes it very hard to pin down the failure to any ONE THING.

Having LWT messages helps to eliminate what is going on.
Or sorry better: Helps if the link IS going up/down like..... (well).....

Because until the bigger picture is clearly seen, we are merely chasing shadows.

Personally I would use/have a LOCAL MQTT broker.
It reduces the points of failure. (IMO)

Though I agree: BIRTH messages would also be handy for the same reason.

[jbudd]

Edit: - corrected image and flow.

This flow can be used to verify each of your MQTT messages has been received by the broker.

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