Kubernetes and OpenShift are two of the most well-known container orchestration platforms. However, comparing the two platforms can sometimes be confusing because Kubernetes is an integral part of OpenShift. This article discusses their key differences, including deployment options, security, networking, and more.
What is Kubernetes?
Kubernetes (K8S) is an open-source platform for deploying, automating, managing, and scaling containerized applications. Kubernetes groups containers into logical clusters to make them easier to manage and discover. K8S can run in both cloud and on-premises environments, including hybrid clouds.
The most important features of Kubernetes are:
- • Load Balancing and Service Discovery: Automatically assigns DNS names, IP addresses, and load levels to pods.
- • Automatic Container Packaging: Ensures resource availability and optimization by placing containers according to their resource requirements.
- • Self-Recovery: Restarts failed containers, replaces containers after node failures, and removes containers that fail health checks.
- • Deploy and Rollback Automation: Roll back to previous versions when problems occur and avoid system crashes when making changes.
- • Batch Launch and Scale: Manually or automatically scale applications and manage batch and continuous integration (CI) workloads.
What is OpenShift?
Red Hat OpenShift is an open-source platform for developing, deploying, and managing containerized applications. OpenShift allows developers to create and deploy Docker-style containers in an integrated development environment (IDE) and then manage them using the Kubernetes platform.
The OpenShift platform supports Node.js, Go, Ruby, PHP, Python, and Java. You can also extend it by adding support for other languages. The platform also enables automatic or manual scaling of containerized applications.
Kubernetes vs. OpenShift: 7 Key Differences
There are several differences between Kubernetes and OpenShift. The list below compares the features of OpenShift and Kubernetes. In this guide, you will find a detailed comparison chart of OpenShift, Kubernetes, and Platform9.
1. Product vs. Project
OpenShift is a commercial product, while Kubernetes is an open-source project. An OpenShift subscription allows users to receive paid support. The subscription also includes CloudForms, which helps organizations manage private, public, and virtual infrastructure. Users must renew their subscriptions periodically based on cluster expansion.
Kubernetes provides a self-sustaining model. In problematic situations, users can contact external experts and the community. The choice between project and product depends entirely on the user.
OpenShift has stronger security features than Kubernetes. OpenShift security policies restrict the use of both simple container images and many official images. OpenShift requires certain permissions to maintain a minimum level of security. As a result, you need to learn the practices to deploy more applications.
The authentication and authorization processes are also different. Installing and configuring Kubernetes authentication requires a lot of effort. OpenShift, on the other hand, offers an integrated server for better authentication.
Both platforms provide authorization through role-based access control (RBAC). The security context is an integral part of Kubernetes. OpenShift has a separate Security Context Constraint (SCC). OpenShift’s approach is better than Kubernetes in terms of security.
3. Web UI
A web-based user interface (UI) is essential for efficient cluster management. You need to install the Kubernetes control panel separately and use the Kube proxy to forward the local machine port to the cluster management server. Additionally, you must manually create a public transport ID for authorization and authentication as there is no login page on the dashboard.
The OpenShift web console has a login page. You can easily access the console and create or modify most resources through a form. You can also map servers, projects, and cluster roles.
4. Deployment method
Kubernetes deployment is done using deployment objects. You can implement controls internally and use them to update pods. Kubernetes deployment objects can handle multiple and concurrent updates.
OpenShift deployment is done using the DeploymentConfig command. You cannot enable DeploymentConfig with drivers. you have to use your own logic.
DeploymentConfig does not support multiple updates such as Kubernetes objects. However, OpenShift DeploymentConfig has other advantages, such as versioning and triggers that control automatic deployment.
You can use both OpenShift and Kubernetes to build a CI/CD pipeline. But no platform offers a complete CI/CD solution. To create a complete CI/CD pipeline, you need to integrate both platforms with additional tools such as automated testing and monitoring and CI servers.
This process is easier in OpenShift because it provides a certified Jenkins container that you can use for the CI server. Plain Kubernetes does not provide an official CI/CD integration solution. To build a CI/CD pipeline with Kubernetes, you need to integrate third-party tools like CircleCI.
6. Integrated image registry
Kubernetes allows you to specify your own Docker registry, but you don’t get an integrated image registry.
OpenShift provides an integrated image registry that you can use with Red Hat or Docker Hub. The image registry has a console where you can search for information about images and image streams for cluster projects.
You can update existing Kubernetes clusters instead of rebuilding them from scratch on both platforms. However, OpenShift and Kubernetes have different update schedules.
In OpenShift, you don’t get notifications when you need to upgrade Kubernetes. To upgrade to the latest version of OpenShift, you must use the Red Hat Enterprise Linux package management system.
Kubernetes normally uses the kubeadm update command to update. On both platforms, you must back up your existing installation before upgrading.
Both Kubernetes and OpenShift enable easy deployment and management of containerized applications. However, there are some differences between them. Installing Kubernetes is complex and often requires a third-party solution. OpenShift has a built-in Kubernetes platform for easy installation but is limited to Red Hat Linux distributions.
When choosing a platform, you should consider your skills and technical knowledge. The goal is to design the pipeline that works best for you, so test and verify the solution before adding the tool to your workflow.