MQTT and bug with the new version?

Jean Michel 5 months ago updated 5 months ago 2

Hi guys!
I've been using the software for Windows for a few years now, and I've never had any "serious" problems, everything always works well, for all our customers (here's the record that I love this product lol).

But now, with the new version 4.10.4, I noticed problems with MQTT communication on all the devices (Tasmota) that I use, they simply cannot connect to the broker, they remain in an eternal "connect / disconnect"!

Here's a photo of the "bench" test settings, in version 4.10.4.

Image 4801

And here is a photo of the "bench" test logs, in version 4.10.4

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After MANY tests on the devices (which I thought was the problem), I decided to try to downgrade the server version, to version 4.9.36, which is the installation I had before the upgrade. (here is a record of the difficulty in finding previous versions, I only found the very old ones, 4.4...)

And to our surprise... Everything works normally again (MQTT and Tasmota).

Here's a photo of the "bench" test settings, in version 4.9.36.

Image 4803

And here is a photo of the installation of version 4.9.36, to prove that I'm not lying lol.

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I have no problem maintaining version 4.9.36, and as I don't have any other device other than Tasmota to connect via MQTT, I understand that the problem could be with these devices.
As I said, everything has always worked well until then...

Did anything change about the MQTT broker compatibility version between versions 4.9.36 and 4.10.4??

In the end, I could just stay in the old version, but I like Comfortclick and IoT devices, so I leave a topic about it for the thousands of users of both who may be looking for some support about it.

Thank you team, and hugs to everyone!


I only have 1 Shelly HT temp/humidity sensor and this is still working on 4.10.4 - it updates values and I don't see any error logs... But I have seen these disconnecting and reconnecting for mqtt devices before. I cant remember what exactly triggered it then. I think I reported it in some ticket but couldn't find it right now. Did you try to do a server reload?

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I got this error then: Devices : 20.09.2023 09:17:46 : Error : Devices\Devices MQTT\MQTT Shelly HT\Client : Error connecting to device. A client with the same client ID is already connected to the broker. Please change client ID. And as i remember server reload fixed it. It may have happened after server update then too.


After identifying the problem and solving it with the downgrade (the goal is to keep it working), in the comfort of our laboratory, the test I did was simply install a new server and just configure a simple MQTT broker and test a device (tasmota), and then I took the photos and opened the ticket.

In the test, there is no way to have devices with the same ID because there is only 1 device (and an MQTT-explorer on another PC). I also tried changing the ID to a more "simple" one, without success.

And yes, I restarted the server in testing lol