https://gitlab.synchro.net/main/sbbs/-/issues/781#note_5579

I'm not clear on how this issue could happen. It looks like a race condition between the broker connection attempt in the terminal server thread and another thread (the event thread) attempting to publish (node status, in this case). But the terminal server thread waits until the MQTT broker connection is either successful or not before continuing and should log the result of the broker-connection attempt:
```
lprintf(lputs, LOG_DEBUG, "MQTT broker-connect (%s:%d) successful", cfg->mqtt.broker_addr, cfg->mqtt.broker_port);
```
or:
```
lprintf(lputs, LOG_ERR, "MQTT broker-connect (%s:%d) failure: %d", cfg->mqtt.broker_addr, cfg->mqtt.broker_port, result);
```

Did you have debug-level log output enabled?
--- SBBSecho 3.20-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

https://gitlab.synchro.net/main/sbbs/-/issues/781#note_5580

I suspect the broker connection *was* successful and you just didn't have debug-level logging turned on.
--- SBBSecho 3.20-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

close https://gitlab.synchro.net/main/sbbs/-/issues/781
--- SBBSecho 3.20-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

reopen https://gitlab.synchro.net/main/sbbs/-/issues/781

Setting up a new system and when sbbs tried to connect to the mqtt service, it reported:

Client <unknown> disconnected due to protocol error.

sbbs reports:
9/3 13:29:02 term MQTT connecting to broker 127.0.0.1:1883

but doesn't say it cannot connect, then proceeds with:

9/3 13:29:02 term Terminal Server ERROR 4 (2) publishing node status
9/3 13:29:02 evnt DAILY ERROR 4 (2) publishing node status

MQTT should probably not try to publish when it's not connected.
--- SBBSecho 3.20-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

https://gitlab.synchro.net/main/sbbs/-/issues/781#note_5903

This issue should be resolved now.
--- SBBSecho 3.21-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)