All Apps and Add-ons

MQTT Modular Input: Does not start, receives error


MQTT Modular Input does not start.

Error Message is:

   Introspecting scheme=mqtt: script running failed (exited with code 1)
   Unable to initialize modular input "mqtt" defined inside the app "mqtt_ta": Introspecting scheme=mqtt: script running failed (exited with code 1)

I changed to log the Java call (see below).

When I start it from a command line, the error appears (not belonging to Java): ERROR Incorrect Program Usage
Nothing else. Any idea?

C:\Tools\jdk-12.0.1\bin\java -classpath C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\commons-codec-1.9.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\commons-logging-1.2.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\httpasyncclient-4.1.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\httpasyncclient-cache-4.1.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\httpclient-4.4.1.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\httpclient-cache-4.4.1.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\httpcore-4.4.1.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\httpcore-nio-4.4.1.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\json.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\log4j-1.2.16.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\mqtt-client-0.4.0.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\mqttmodinput.jar;C:\Tools\Splunk\etc\apps\mqtt_ta\bin\lib\splunk_tlsv12.jar; -Xms64m  -Xmx64m  -Dsplunk.securetransport.protocol=tls com.splunk.modinput.mqtt.MQTTModularInput


This is very late, but I ran into the same error.

I saw a hint at

I also found a page about troubleshooting add-ons:

Which allowed me to find the following log from the add-on for more information:

07-20-2020 06:43:40.050 +0000 ERROR ModularInputs - <stderr> Introspecting scheme=mqtt: java: symbol lookup error: java: undefined symbol: JLI_StringDup

And then I found this bug:

So I downgraded to openjdk-8 and all is well for me (I was on openjdk-11). I see that you're running jdk-12, which is likely to be your problem.

0 Karma
Get Updates on the Splunk Community!

Admin Your Splunk Cloud, Your Way

Join us to maximize different techniques to best tune Splunk Cloud. In this Tech Enablement, you will get ...

Cloud Platform | Discontinuing support for TLS version 1.0 and 1.1

Overview Transport Layer Security (TLS) is a security communications protocol that lets two computers, ...

New Customer Testimonials

Enterprises of all sizes and across different industries are accelerating cloud adoption by migrating ...