Kubernetes vs OpenShift: What Is the Difference?
Check out the essential differences between Kubernetes and Red Hat's open source alternative.
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Containerization is the new buzz word for developing and deploying apps since they are an efficient way to accelerate development. Container usage has grown exponentially in the last years.
However, managing containers across the infrastructure can become such a complex task that a container management platform is an essential vehicle for any organization. Kubernetes and OpenShift are two of the most popular container management platforms in the market. What makes it interesting is that OpenShift is based on Kubernetes. Read on to learn more about their features and differences.
What Is Red Hat OpenShift?
OpenShift is a containerization software solution developed by Red Hat. Their main product is the OpenShift Container Platform, a Platform-as-a-Service (PaaS) orchestrated and managed by Kubernetes. It was written in Go and AngularJS and has an Apache License.
OpenShift Origin is Red Hat’s open-source cloud-based platform, allowing developers to build, test and deploy applications to the cloud. The system adds tools on top of a Kubernet core to enable faster application development, easy deployment and scaling.
The platform supports Go, Node.js, Ruby, Python, PHP, Perl, and Java besides being extensible to allow users can add support for other languages. Regarding scalability, the platform enables the scaling of containerized applications automatically or manually.
Some of the features OpenShift offers are:
- Constant security—security checks are built into the container stack across the application lifecycle.
- Built-in monitoring—included on the platform is Prometheus, a database and application monitoring software. You can visualize the applications in real-time on a Grafana dashboard.
- Centralized policy management—a single console across clusters gives users a centralized place to implement policies.
- Compatibility—OpenShift is part of the Certified Kubernetes program, therefore allowing compatibility with Kubernetes container workloads.
Benefits of working with OpenShift include:
- Fast application development—the platform streams and automates the container management process, therefor enhances the DevOps process. This acceleration of the application development means you can go to market faster, allowing to be competitive.
- No vendor lock-in—provides a vendor-agnostic open-source platform, which means that users can migrate their container processes to new operating systems if needed, without the need to redo their containerization orchestration.
- Self-service provisioning—OpenShift allows users to integrate the tools they use most, for example, a video game developer can use this feature when developing games compatible with several operating systems.
What Is Kubernetes?
Kubernetes is an open-source container as a service (CaaS) orchestration system for automating the deployment, scaling, and management of containerized applications, thus improving the applications development process. Some of Kubernetes’ features include:
- Processes automation—for example, which server will host the container.
- Self-monitoring—the platform provides constant checking of the health of servers and containers.
- Scalability—one of its main features is that it allows horizontal scaling, enabling organizations to quickly scale out their storage according to their workload needs.
- Flexibility—as an open-source cloud-based tool, you can run it in multiple environments, be on-premises, hybrid or public cloud infrastructure.
- Container balancing—the platform calculates automatically the best location for a container.
- Storage orchestration—integrates with most storage systems, meaning you can integrate Kubernetes with your AWS Elastic Storage, for example.
Benefits of working with Kubernetes include:
- Mature architecture—built on over a decade of Google engineers experience.
- Ongoing development—Kubernetes large and active community releases new features constantly. The user community works as a support network fostering collaboration.
- Rich application support—supports a wide spectrum of programming languages and frameworks. This flexibility enables Kubernetes to satisfy a varied range of use cases.
Differences Between OpenShift and Kubernetes
Since OpenShift is based on Kubernetes, it makes sense that they have a lot in common. However, there are several differences between both platforms. Let’s have a comparison of OpenShift and Kubernetes features:
While both based on Linux, each product runs in a different environment:
Kubernetes is more flexible regarding the Operating Systems it can run on. However, the package manager should be RPM, meaning a Linux distribution. Therefore it is better to run it on Fedora, Ubuntu or Debian. Kubernetes can be deployed on any major IaaS platform, such as AWS, Azure, and GCP.
OpenShift can be installed on the Red Hat Enterprise Linux (RHEL) and the Red Hat Enterprise Linux Atomic Host (RHELAH), as well as Fedora and CentOS. OpenShift Dedicated, allows getting your own cluster in the cloud, specifically based on Amazon Web Services.
Both products are complex in terms of rolling out:
The diversity of platforms Kubernetes runs on means that there are myriad of solutions to create Kubernetes clusters on-premises. Most are based on installers such as Rancher Kubernetes Everywhere (RKE) or kops, an installer of Kubernetes to roll out OpenShift on AWS.
OpenShift aims to avoid the need for additional components after the initial rollout. Therefore comes with its proprietary Ansible-based installer, which can install OpenShift with minimal configuration parameters.
There is a big difference between OpenShift and Kubernetes relative the ability to administrate the cluster via a web-based user interface.
Kubernetes's dashboard has to be installed separately and needs to be accessed through the kube proxy to forward a port of your local machine to the cluster’s admin server. Moreover, it does not have a login page, but you need to manually create a bearer token to provide authentication and authorization. All this complication results in a web UI that is not very valuable for real day-to-day administrative work.
OpenShift's web console has a login page, can be easily accessed, and even gives you the ability to create and change most resources through a form. While you cannot administrate the cluster via the web you can visualize servers, projects, and cluster roles.
Integrated Image Registry
Here there is a key difference between both systems regarding an integrated image registry.
With Kubernetes, you may set up your own Docker registry, but there is no concept of an integrated image registry.
OpenShift comes with an integrated image registry that can be used with Docker Hub or Red Hat. It even has a registry console where you can search for information about images and image streams related to projects in a cluster.
While the concept doesn’t exist in Kubernetes, you can deploy your own custom Jenkins image. The resulting artifacts are docker images uploaded to an image repository.
OpenShift uses Pipeline build, a form of source-to-image build that refers to an image containing a Jenkins which in turn monitors ImageStreamsTags. When there is a need to update, it can start a Jenkins build.
Kubernetes does not have a native networking solution but offers interfaces that can be used by third-party network plugins.
OpenShift has a native networking solution out-of-the-box, OpenvSwitch, which offers three different plugins.
Which One Is Better?
Both are open-source software platforms aiming to facilitate container orchestration and application development. They make it possible to deploy and manage containerized apps in an easy and manageable way. OpenShift web console makes it very useful, allowing to perform over 80% of tasks directly through it.
Although both have a similar core (after all, OpenShift has Kubernetes built into it) OpenShift makes installing easier with its out-of-the-box features. Installing Kubernetes often requires a turnkey solution or managed Kubernetes clusters.
The system you choose will depend on the requirements of your system and how critical flexibility or a good web interface are for your development process.
Published at DZone with permission of Gilad David Maayan. See the original article here.
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