I'm searching for a main difference between OpenShift V3 and V2. Is OpenShift V2 working like this?: https://www.openshift.com/walkthrough/how-it-works And how are Docker and Kubernetes working in V3?
Can someone give me a clear explanation about the build-up of OpenShift V2 and V3
This is a rather broadly asked question, so I will (and can) answer only in a rather broad manner.
There are a lot of key concepts that have changed. These are the most important ones and you'll need some time to get into it, but they are a big improvement to OpenShift v2.:
When you'll study the links below you will understand, that (really exaggerated) OpenShift v3 has basically nothing to do with v2 besides the name, the logo and the PaaS focus. But it's still a great tool and IMO has set new standards in the PaaS-world. (No, I don't work for RedHat ;)
What's New:
https://docs.openshift.com/enterprise/3.0/whats_new/overview.html https://docs.openshift.com/enterprise/3.0/architecture/overview.html
For starters; Docker & Kubernetes:
https://blog.openshift.com/openshift-v3-platform-combines-docker-kubernetes-atomic-and-more/
Pretty new:
Creating a Kubernetes Cluster to Run Docker Formatted Container Images
EDIT 2016_06_30: Sorry for necro'ing this old post, but I wanted to add this quick, fun and very informative video about Kubernetes: https://youtu.be/4ht22ReBjno