OpenShift and Kubernetes are both powerful container orchestration platforms that have gained significant traction in recent years. While they share many similarities, there are key differences that set them apart. This blog post will delve into the key features, benefits, and considerations between OpenShift and Kubernetes.
Kubernetes: The Foundation of Modern Orchestration
Kubernetes is a powerful platform designed to streamline the management and operation of containerized applications. It accomplishes this by organizing containers into logical groupings known as pods. These pods represent cohesive units of application functionality, making it easier to deploy, scale, and monitor the application as a whole. By treating groups of containers as single entities, Kubernetes simplifies complex operational tasks and improves overall efficiency. Leveraging over 15 years of Google's experience in managing production workloads, combined with the collective wisdom of the open-source community, Kubernetes offers a robust and proven solution for container orchestration.
What is a Kubernetes cluster?
A Kubernetes cluster is essentially a group of computers (nodes) that work together to run containerized applications.
- Nodes: Worker machines that run containerized applications. They are managed by the control plane.
- Control Plane: A set of processes that manage the cluster state and provide the Kubernetes API. It includes components responsible for scheduling, service discovery, load balancing, and other core functionalities.
Key Components and Functionalities:
- Master Node: The central component of the control plane responsible for overall cluster management.
- Worker Nodes: The compute resources where containers are deployed and executed.
- Pods: The smallest deployable units of computing, consisting of one or more containers, shared storage, and network configuration.
- Services: An abstraction that defines a logical set of Pods and a policy for accessing them.
- Controllers: Processes that ensure the desired state of the cluster is maintained.
- API Server: The control plane's front-end for interacting with the cluster via the Kubernetes API.
- Scheduler: Decides which node to place a newly created Pod on.
- etcd: A key-value store used to store the cluster state.
Key Benefits of Kubernetes
- Automated rollouts and rollbacks: Kubernetes safely deploys updates, monitors app health, and automatically rolls back failures.
- Service discovery and load balancing: Kubernetes simplifies service discovery by assigning unique IP addresses and DNS names to Pods, allowing applications to communicate without complex configuration changes.
- Storage orchestration: Automatically mount any storage. whether from local storage, a public cloud provider, or a network storage system such as iSCSI or NFS.
- Self-healing: Kubernetes automatically manages container lifecycles: restarts failed containers, replaces dead ones, removes unhealthy containers, and ensures only healthy containers are accessible.
- Secret and configuration management: Manage secrets and configs without rebuilding your app or exposing them publicly.
- Automatic bin packing: Kubernetes intelligently places containers on nodes based on their needs, ensuring high availability. It optimizes resource use by combining critical and less critical workloads.
- Horizontal scaling: Easily scale your app up or down manually or automatically based on usage.IPv4/IPv6 dual-stack: Allocation of IPv4 and IPv6 addresses to Pods and Services
- Designed for extensibility: Add features to your Kubernetes cluster without changing upstream source code.
OpenShift: Enterprise-Grade Kubernetes with Added Features
OpenShift, developed by Red Hat, is a Kubernetes distribution that adds a layer of enterprise features and enhanced usability on top of the base Kubernetes platform. It aims to simplify the deployment and management of containerized applications by providing a more integrated and user-friendly experience.
Key Features of OpenShift:
- Developer and Operational Tools: OpenShift includes a suite of tools that streamline development, deployment, and management processes. This includes an integrated developer console and CI/CD pipelines.
- Security: OpenShift emphasizes security with features like Security Context Constraints (SCC), which provide additional controls over container privileges and interactions.
- Integrated Container Registry: OpenShift comes with an integrated image registry, making it easier to manage and deploy container images securely.
- Operator Framework: OpenShift leverages Kubernetes Operators to manage complex applications and services, providing enhanced automation and operational consistency.
- User-Friendly Interface: The OpenShift web console and CLI tools are designed to be more accessible for developers and operators, providing a more streamlined user experience compared to the raw Kubernetes API.
OpenShift Use cases
- Application development and delivery: Streamline workflows to get to production faster, including built-in Jenkins pipelines and the source-to-image technology to go straight from application code to container.
- Virtualization: Take advantage of a cloud-native approach to virtual machines (VMs).
- Modernize existing apps: Bring together development, operations, and security teams under a single platform to modernize existing applications while accelerating new cloud-native app dev and delivery.
- AI/ML: Develop and train AI models and run AI-enabled applications anywhere—in the cloud, the edge, and on-premises.
- Edge computing: Extend application services to remote locations and analyze inputs in real time with Red Hat OpenShift’s edge computing capabilities.
When to Choose OpenShift
- Enterprise-grade support: If you require a robust support infrastructure for your containerized applications.
- Integrated services: If you need a comprehensive platform with built-in tools and services for development, deployment, and management.
- Managed services: If you prefer to offload the management of infrastructure components to a managed provider.
- Red Hat ecosystem: If you are already invested in the Red Hat ecosystem and want a cohesive solution for your containerized applications.
The difference between OpenShift and Kubernetes
OpenShift builds upon Kubernetes to offer a more comprehensive and integrated platform for managing containerized applications. While Kubernetes provides the foundational orchestration capabilities, OpenShift extends and enhances these capabilities with additional features and tools. Here’s a detailed look at what OpenShift adds to Kubernetes:
| Kubernetes Open source container orchestration | |||
Push-button, automated node configuration and tools | | |||
Multi-host-container scheduling | | | ||
Self-service provisioning | | | ||
Service discovery | | | ||
Enterprise container host operating system | | |||
Container Image registry | | |||
Validated storage plug-ins | | |||
Networking and validated plug-ins | | |||
Monitoring | | |||
Log aggregation | | |||
Service Mesh | | |||
Multitenancy | | |||
Metering and chargeback | | |||
Cloud service broker | | |||
Automated image builds | | |||
CI/CD and DevOps workflows and pipelines | | |||
Validated third-party Kubernetes operators and Helm charts | | |||
Certified databases and related data services | | |||
Certified application services | | |||
200+ certified ISV solutions | | |||
Multi-cluster management | | |||
Zero downtime patching and upgrades | | |||
Enterprise 24/7 support | | |||
9-year support lifecycle | | |||
| |
In conclusion, both OpenShift and Kubernetes offer robust solutions for managing containerized applications, but they cater to different needs. Kubernetes provides a flexible and powerful base for container orchestration, while OpenShift builds upon Kubernetes to offer a more integrated and secure platform with added developer and operational tools. Understanding the strengths and differences of each can help you make an informed decision that aligns with your organization’s goals and expertise.
References:
https://www.redhat.com/en/topics/containers/what-is-kubernetes
https://www.redhat.com/en/technologies/cloud-computing/openshift#summary
https://www.redhat.com/en/technologies/cloud-computing/openshift/red-hat-openshift-kubernetes