B4J Question [SOLVED] Connecting to Moqsuitto MQTT Broker-Server with Credentials/SSL Strange Problem !


Licensed User
Longtime User
Hi there...

Well I have a very very strange problem...

First of all - I am using the same code to connect at 3rd party server having "Credentials" and "SSL" (the same way - with lets encrypt). Works at debug/release and standalone package perfect.

1) I ve installed at my Debian VPS server a mosquitto broker 3.1/v3.1.1 as saying... not allowing anonymous !, created ssl for it, opened firewall port added a text file with usernames, passwords

2) I am connecting from B4J ide when running my project... succesfully... debug / release mode

3) but when I am trying from standalone package exe or debug.bat (at my server)... can;t connect like username/password are not right... the only way to connected is when enanbling anonymous access from server side...


Here the screenshot from IDE:


using those libs:

I am uploading also the project (MQTTstrange.zip) ... but the strange problem is only at my server... not at 3rd paty servers... I know this is somehow difficult to test
also uploading .conf of mosquitto server (mosquitto.zip)_... if helps

using Let's Encrypt SSL... and without it ... with simple tcp access had the same working from IDE but not from Standalone Package... hmmm

Thanks in advance


  • MQTTstrange.zip
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  • mosquitto.zip
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