Failed to instantiate SLF4J LoggerFactory

SonarQube Version: 8.6

Post Log4j vulnerability we began looking at moving to a supported version of sonarqube. No changes were made as far as we know, only viewing of config files and a snapshot of the VM. However, now the SQ instance returns a 503, restarting the instance fails and we have restarted all the services.

The Bitnami diagnostic tool was used and they extracted the following from the logs:

SLF4J: Found binding in [jar:file:/opt/bitnami/apps/sonarqube/sonarqube/lib/common/logback-classic-1.2.3.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See for an explanation.
Failed to instantiate SLF4J LoggerFactory
Reported exception:
java.lang.NoClassDefFoundError: org/apache/logging/log4j/spi/AbstractLoggerAdapter
    at java.base/java.lang.ClassLoader.defineClass1(Native Method)
    at java.base/java.lang.ClassLoader.defineClass(
    at java.base/
    at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(
    at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(

It would appear that all other services are running but SonarQube cannot be restarted.


Welcome to the community!

It’s nearly impossible to know what happened to make your current SonarQube instance stop working. What I do know is that if you go ahead & upgrade to at least 8.9.6, your download will be a complete bundle with all the parts you need to spin up your instance.

Sorry to dodge the question, but we’re just not in a position to diagnose 8.6 anymore.