Getting Started with OneKS on

Overview

Tue, 12 May 2026 00:00:00 +0000

OneKS provides Elastic Kubernetes as a Service on OpenNebula. It offers a structured way to create, access, operate, upgrade, recover, and deprovision Kubernetes Clusters (K8s Clusters) by combining a user-facing service layer with Cluster API-based infrastructure provisioning through CAPONE, the Cluster API provider for OpenNebula.

OneKS is designed for teams that need a simple and repeatable way to consume Kubernetes inside OpenNebula. Typical use cases include development and test environments, self-service Kubernetes delivery in private cloud environments, and standardized Cluster offerings for different sizes and topologies.

Basic Configuration

Tue, 12 May 2026 00:00:00 +0000

Before creating a K8s Cluster, ensure that the minimum required components are configured and available.

Install and Configure the OneKS Service

Install the OneKS package on the OpenNebula Front-end if it is not already installed:

sudo apt install -y opennebula-ks

OneKS uses an appliance from the OpenNebula Marketplace to bootstrap K8s Clusters. By default, it imports this appliance into the default OpenNebula image datastore when the service starts. Ensure that this datastore is accessible to the OpenNebula Cluster where K8s Clusters will be deployed. To make the appliance available to additional Clusters or configure it for air-gapped environments, see Appliance Configuration.

Quick Start

Tue, 12 May 2026 00:00:00 +0000

This quick-start guide uses the Sunstone Web UI to demonstrate a short first-use workflow for deploying a simple K8s Cluster with OneKS. CLI and API workflows are covered in K8s Cluster Lifecycle Management. Before beginning this quick-start guide, ensure to complete the steps in the Basic Configuration Guide.

Quick-start workflow:

Prepare the Environment: Verify the minimum OneKS, OneGate, networking, profile, and permission requirements.
Create the K8s Cluster: Use the Sunstone Web UI K8s Cluster creation wizard.
Wait for the K8s Cluster: Wait until the K8s Cluster reaches the RUNNING state.
Retrieve kubeconfig: Copy the kubeconfig from the K8s Cluster detail view.
Validate Kubernetes Access: Run kubectl get nodes using the retrieved kubeconfig.
Add Worker Capacity: Create a node group if worker nodes are required.
Validate Workload Deployment: Deploy a simple NGINX workload and test in-cluster service connectivity.

Create a New K8s Cluster

From the left-hand navigation menu in Sunstone, go to Kubernetes -> K8S Clusters:

Core Concepts

Tue, 12 May 2026 00:00:00 +0000

This section explains the main concepts behind OpenNebula Elastic Kubernetes Service (OneKS). This service exposes Kubernetes Clusters as high-level resources while orchestrating the OpenNebula, Cluster API, CAPONE, and runtime components required to provision and operate them.

Users mainly interact with:

K8s Clusters: Top-level resources representing Kubernetes Clusters deployed on OpenNebula.
Node Groups: Scalable worker-capacity groups attached to K8s Clusters.
Profiles, Families, and Flavours: Reusable configuration models that define the deployment options exposed to users.
Lifecycle Operations: Create, inspect, access, scale, upgrade, recover, and delete operations exposed through Sunstone, the CLI, and the API.

Lower-level resources such as OpenNebula VMs, templates, images, networks, virtual routers, Cluster API objects, and CAPONE resources are managed internally through these abstractions.