Questions

1. What are the major differences between a virtual machine and a Docker container?
2. What is the purpose of namespaces and cgroups in Docker?
3. What happens with a Java application that doesn’t honor the max memory settings in a container and allocates more memory than it is allowed to?
4. How can we make a Spring-based application run as a Docker container without requiring modifications of its source code?
5. Why will the following Docker Compose code snippet not work?

     review:
       build: microservices/review-service
       ports:
         - "8080:8080"
       environment:
         - SPRING_PROFILES_ACTIVE=docker
     product-composite:
       build: microservices/product-composite-service
       ports:
         - "8080:8080"
       environment:
         - SPRING_PROFILES_ACTIVE=docker