Deployment of spring boot app failing on tomcat v 8.5

Question

I have application developed in spring boot (v 1.5.9.RELEASE) which is working with tomcat v 7.0

I need to upgrade to new version of tomcat v 8.5. I have installed it ( apache-tomcat-8.5.32) and tried to deploy the same app. But I am getting exception while deployment of app.

Exception is with slf4j and log4j multiple bindings. I have started development of my app with Spring Initializr tool ( https://start.spring.io/ )

How can I fix this issue? As I am not aware of which specific dependency causing this issue and where do I need to add exclusion. Please help with this.

Answer 1

Well, AFAIK Spring Boot uses Logback by default rather than SLF4J. So I suspect that's where the multiple bindings issue comes from ( documentation ).

Your logging should contain a message mentioning what bindings clash, you can use mvn dependency:tree to figure out where it comes from. Also see this and this answer.