How to compare dockers with openshift?

Question

Docker and OpenShift are both structures for implementing PaaS.

How do they compare in architecture and function?

Answer 1

The main difference is that Docker as a project is focused only on the runtime container, while OpenShift (as a system) includes both the runtime container and the REST API, coordination and web interfaces for deploying and managing individual containers.

Comparing runtime containers only, OpenShift and Docker use kernel isolation functions to separate tenant processes. For Docker, this is, first of all, LXC and OpenShift, which is largely ensured by SELinux security and multiple category (MCS). Both use groups to limit the CPU, memory, and IO of tenants. Upstream OpenShift reviews LXC to reduce long-term efforts.

Docker uses AUFS to share disks and files with copy to write, OpenShift does not require and is not compatible with such a system.

Inside the container, OpenShift models units of functionality (web servers, dbs) through "cartridges", which are a set of shell script commands that are called when the system is called. The API is described here . The cartridge is approximately similar to the image of the docker.

Openshift also describes an API through which a broker (coordinator) communicates with nodes (servers that host multiple tenant containers) to call endpoints in this container.

EDITED ADD: Starting in June 2015, OpenShift Origin 1.0 runs on top of Docker and Kubernetes, and you can create and develop multi-container applications that run during Docker execution. OpenShift adds assembly, image manipulation and promotion, and also protects cluster cluster operations on Kube and Docker

Answer 2

Here is a distant best explanation for a beginner. https://deis.com/blog/2016/kubernetes-illustrated-guide/

This is not a joke, sometimes we need to look at things like a child in order to really understand.

I would not say that they are even comparable. Openshift is a corporate solution from redhat, which is based on quernets. Kubernetes is just the foundation for organizing and automating work with docker containers. I would start with the video, and then look at the cupernets at a lower level. Once you feel comfortable, start exploring the features that the addition adds.

Answer 3

I found some interesting readings about this topic over the past two years:

• Openshift is a PaaS architecture using docker container technology .
• It just happened not so long ago when openshift changed from gears to docker pods .
• The technology fits into the large cloud stack architecture as a whole at level 3, PaaS. The remaining layers in the model: 0 - hardware; 1 - software data center; 2 - main PaaS; 4 - model-driven PaaS; 5 - application maintenance; 6 - SaaS.

Answer 4

I thought I should update the answers to this question with information available towards the end of 2018.

The situation is now a little more complicated than when the question was originally asked. Currently Docker Inc. is the main developer of Docker and Moby, which is currently the main project for the Docker runtime and the commercial version of Docker, figuratively called the Docker Enterprise Edition.

A modern analysis of this issue will lead to a comparison of Docker Enterprise Edition with RedHat OpenShift. These container platforms are in direct competition with each other, and both are considered Kubernetes distributions that can be run both on-site and in the cloud. At the time of this writing, Docker Inc. Docker-EE was a leader in terms of capabilities and sales, but there is fierce competition from public cloud providers who offer kubernetes Platform (s) as a service and are starting to move. into more advanced server container platforms.