In an application using log4j with slf4j, I am trying to use a dependency (elasticsearch in this) which depends on log4j2.
The application's logging dependency looks like this- <dependency> <groupId>org.elasticsearch</groupId> <artifactId>elasticsearch</artifactId> <version>5.6.16</version> </dependency> <dependency> <groupId>org.elasticsearch.client</groupId> <artifactId>transport</artifactId> <version>5.6.16</version> </dependency> <dependency> <groupId>org.apache.logging.log4j</groupId> <artifactId>log4j-to-slf4j</artifactId> <version>2.11.1</version> </dependency> The application is using its own log4j.xml and has some custom appenders of log4j so it cannot be migrated to log4j2 without rewriting the appenders. Added the below dependencies as suggested in elasticsearch documentation <https://www.elastic.co/guide/en/elasticsearch/client/java-api/current/_using_another_logger.html> for using a different logger other than log4j2. <dependency> <groupId>org.apache.logging.log4j</groupId> <artifactId>log4j-to-slf4j</artifactId> <version>2.11.1</version> </dependency> But now on starting the application, I am seeing some warnings like below DEBUG StatusLogger org.slf4j.helpers.Log4jLoggerFactory is not on classpath. Good! DEBUG StatusLogger Using ShutdownCallbackRegistry class org.apache.logging.log4j.core.util.DefaultShutdownCallbackRegistry WARN StatusLogger Multiple logging implementations found: Factory: org.apache.logging.log4j.core.impl.Log4jContextFactory, Weighting: 10 Factory: org.apache.logging.slf4j.SLF4JLoggerContextFactory, Weighting: 15 Using factory: org.apache.logging.slf4j.SLF4JLoggerContextFactory Can someone let me know what does this warning denote? How can I remove it?