Openshift Admin: How to add node to the cluster in openshift Local

To add a node to an OpenShift cluster running locally using OpenShift Local (previously known as CodeReady Containers or CRC), the process involves configuring a multi-node cluster in OpenShift Local. However, OpenShift Local is designed for single-node clusters primarily for development and testing purposes. It doesn’t natively support multi-node setups as part of the CRC deployment. That said, you can try a few different approaches to simulate a multi-node setup.

Here’s a high-level guide on how to simulate adding additional nodes or a multi-node environment with OpenShift Local:

Option 1: Use OpenShift in a Virtual Machine for Multi-Node Setup

If you require multiple nodes for testing, a good approach is to deploy OpenShift in a virtualized environment (e.g., using minikube or Vagrant).

Using Minikube (for Multi-Node Simulation)

Minikube is a tool that allows you to run a multi-node OpenShift cluster on your local machine (even if OpenShift Local is a single-node setup).

1. Install Minikube if you haven’t already:
   • Follow the instructions here: https://minikube.sigs.k8s.io/docs/
2. Start a multi-node OpenShift cluster:
   You can simulate a multi-node cluster using Minikube with a configuration for multiple nodes: minikube start --nodes 3 --driver=virtualbox In this setup, Minikube will create a multi-node Kubernetes/OpenShift-like environment that you can use to simulate adding nodes. OpenShift will be deployed on a VM, and the control plane and worker nodes will be simulated.

Using OpenShift in VirtualBox (for Development)

1. Download OpenShift Installer from Red Hat:
   OpenShift CLI (oc).
2. Create Virtual Machines: You can use VirtualBox (or any hypervisor) to manually create nodes. Each VM can be configured as a control plane or worker node.
3. Set up OpenShift using the openshift-install tool:
   • Install OpenShift manually by using the OpenShift installer.
   • Choose a manual installation process for multi-node clusters.
   • Follow official OpenShift documentation for setting up a local multi-node environment.

Option 2: Use OpenShift for Developers (Single Node Local Cluster Simulation)

In case your requirement is only for testing or development on a single-node cluster, OpenShift Local (CRC) is suitable. You cannot directly add additional nodes to a CRC setup, as it’s designed to be a minimal, local environment.

Steps for CRC Setup:

1. Download and Install CRC:
   • Follow the steps in the official OpenShift CRC documentation.
2. Start CRC Cluster:
   • After installation, run: crc start
3. Access OpenShift Dashboard:
   • The crc setup will give you access to a fully functional OpenShift environment on a single node via oc and a web console.
4. Verify Node:
   • Check the current node in the CRC environment: oc get nodes
   You will see that it is running a single node.

Option 3: OpenShift 4.x – Use oc to simulate nodes (limited)

In OpenShift 4.x or higher, you can simulate multi-node configurations by using multi-architecture clusters with specific configurations. This is more of a testbed setup and is not typical for production.

Option 4: Deploy OpenShift with openshift-installer

If your requirements extend beyond a local developer environment and you want to create a more robust cluster on your local machines, you can use openshift-installer to deploy OpenShift in a multi-node configuration, but this typically requires a more complex local setup.

1. Use the OpenShift Installer to configure a bare-metal or VM-based cluster.
2. Set up your control plane and worker nodes as separate machines or VMs.
3. After the cluster is set up, you can add worker nodes using the OpenShift Installer:
   • You can add worker nodes by manually modifying the inventory file used by the installer.

Summary

• OpenShift Local (CRC) is designed for single-node environments for local development and testing. You can’t natively add more nodes to the same CRC cluster.
• For a multi-node setup, consider using tools like Minikube or OpenShift Installer on virtualized environments or physical machines.

Would you like further clarification or assistance with setting up a multi-node simulation using any of these methods?

Rajesh Kumar

I’m Rajesh Kumar, a DevOps, SRE, DevSecOps, Cloud, and Platform Engineering expert passionate about sharing practical knowledge, real-world experiences, and industry best practices. I have worked at Cotocus and regularly write about technology, travel, investing, health, product reviews, and digital marketing through my various platforms.

I publish technical articles at DevOps School, travel stories at Holiday Landmark, stock market insights at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow, and SEO and digital marketing strategies at Wizbrand.