I am trying to migrate from spring boot 1.5 tio 2.0 and faced problem: I changed version of spring-cloud-netflix-core from 1.3.4.RELEASE to 2.0.1.R
Since the 2.x release Spring Cloud moved the netflix feign classes to their own project.
2.x
https://github.com/spring-cloud/spring-cloud-openfeign
You need to update your re-import with the correct package
org.springframework.cloud.openfeign