I think my MQTT / Mosquitto addon is borked...

[candid scarab]

Since last night all of a sudden 2 addons that I got that use MQTT are apparently unable to connect to it out of the blue.
1 is Zigbee2MQTT and the other is an addon for my car (MG4)
Both worked well before then suddenly nothing.

Here is what I see in the logs:

Mosquitto/MQTT addon (also looping):

2025-06-25 10:26:17: New connection from 172.30.32.1:43254 on port 1883.
2025-06-25 10:26:17: New client connected from 172.30.32.1:43254 as saic-python-mqtt-gateway (p2, c1, k60, u'mqtt-user').
2025-06-25 10:26:17: Client saic-python-mqtt-gateway closed its connection.
2025-06-25 10:26:46: New connection from 172.30.32.2:43208 on port 1883.
2025-06-25 10:26:46: Client <unknown> closed its connection.

Any help appreciated. System is on a ssd on an intel based mini PC

Adding more logs

[idle flame]

At least Z2M isn't failing because of MQTT but because the USB stick isn't responding.

Have you tried a power cycle of the complete system?

[candid scarab]

I will try. actually Z2M is using SMlight on the network not via USB.

[candid scarab]

I got another integration that's failing and also uses MQTT... 😦

[idle flame]

Did a full system power cycle? Thus not only a HA restart but a host reboot?

because Z2M can't find the network based adapter and other devices connect via the network as well I do expect a network issue. I see nothing wrong in the MQTT log

[candid scarab]

I'll do it right away thank you!

[candid scarab]

The full restart did not help sadly 😦

[idle flame]

You run HA OS bare metal?
Did you change anything to your network?
Did you try to connect to the MQTT from your computer (MQTT Explorer for example)? (Although I don't think it's a MQTT problem).

[candid scarab]

@idle flame I did not change anything and I did not try to connect from my computer. I can try that

[candid scarab]

I was able to connect and I can see some topics and on the Mosquitto broker I can see some logs.. so nooooow back to solving z2m 😬

[idle flame]

the path to the stick is by IP? Does it have a fixed IP?

[candid scarab]

Yes it's a fixed IP btw thanks so much for the time you're putting towards helping me 🙏🏻

[idle flame]

Can reach the stick from your computer? Power cycle of the stick?
No need to hide local IP's 🙂
(and btw, you can leave the whole MQTT section just empty if you use the MQTT broker addon.)

[candid scarab]

yes I can access the SLZB-06 web interface at the IP

o I'll try to uninstall and re install z2m?

That's on the stick

[idle flame]

never seen that do anything. Stick and HA both just wired? Or Wifi involved?

[candid scarab]

HA wired and Stick on wifi

but it's been that way for months

[idle flame]

Yeah, but like everything (including neighbors) can influence wifi 😐 Tried a power cycle of the stick? And is it up to date (both firmwares)

[candid scarab]

I will power cycle after my meeting. it is up to date

I also found out that for my MG car the credentials had expired 🤦🏻‍♂️

So basically I only have Z2M not working and you were right all along, MQTT is fine