Questions

Please solve the following questions to assess your learning progress:

1. Which statements are correct (multiple answers are possible)?
   1. A container is kind of a lightweight VM
   2. A container only runs on a Linux host
   3. A container can only run one process
   4. The main process in a container always has PID 1
   5. A container is one or more processes encapsulated by Linux namespaces and restricted by cgroups
2. Explain to an interested layman in your own words, maybe using analogies, what a container is.
3. Why are containers considered to be a game changer in IT? Name three to four reasons.
4. What does it mean when we claim: If a container runs on a given platform then it runs anywhere...? Name two to three reasons why this is true.
5. True or False: Docker containers are only really useful for modern greenfield applications based on microservices. Please justify your answer.
6. How much does a typical enterprise save when containerizing their legacy applications?
   1. 20%
   2. 33%
   3. 50%
   4. 75%
7. Which two core concepts of Linux are containers based on?