CfgMgmtCamp 2026 Ghent

From Zero to Immutable Kubernetes: Your First Cluster, Step by Step

Abstract

Immutability at the OS level is gaining traction as a way to simplify, secure, and scale Kubernetes operations — without the fragility of hand-crafted node configurations or the false sense of control offered by traditional configuration management systems, which often still result in drift and snowflakes. In this hands-on workshop, you’ll learn how to build Kubernetes clusters that are easier to deploy, upgrade, and recover — and do it all step-by-step, without needing to become an OS expert.

You’ll learn how to:

  • Understand what an immutable OS is and why it matters
  • Deploy Kubernetes on top of an immutable system
  • Add and manage read-only worker nodes
  • Upgrade nodes manually or via Kubernetes-native workflows
  • Create your own tailored, immutable OS image
  • Integrating OS builds into your CI/CD pipelines

If time allows, we’ll also explore:

  • Air-gapped and hybrid-cloud deployments
  • PXE/netboot cluster bootstrapping
  • Trusted Boot with TPM/UEFI
  • High-availability setups on immutable infrastructure
  • Raspberry Pi and edge use cases with mesh networking

All examples will be built using Kairos, an open-source Linux toolkit designed to make immutability practical and flexible — but the patterns you’ll learn are applicable beyond any single tool.

Audience

This workshop is designed for platform engineers, SREs, and solution architects who need more flexibility than fully managed Kubernetes solutions typically allow — but who also want to avoid taking on the burden of maintaining yet another complex system. If you’re comfortable with Linux, familiar with Kubernetes basics, and can spin up a VM or cloud instance, you’ll leave with real-world skills you can apply immediately.


Outline

  1. What are immutable OS and how to think about operations with this paradigm

Explore the philosophy and architecture of immutable systems versus traditional configuration management tools. Learn how immutability enables atomic upgrades, reduced drift, simplified recovery, and stronger security postures.

Resources

  1. Introduction to Kairos and its major concepts

Get familiar with Kairos as a cloud-native, distro-agnostic, immutable Linux meta-distribution. Understand key concepts like A/B system partitions, persistent data separation, recovery mode, and cloud-config-driven provisioning.

Resources

  1. Deploying a single-node cluster

Deploy Kairos on a VM or bare-metal machine and initialize a Kubernetes control plane using K3s and cloud-init. Validate node readiness and explore initial workloads.

Resources

  1. Build your own immutable OS

Use the Kairos Factory (from the Web or CLI) to create a custom immutable OS image tailored to your needs. Learn how to configure the base system, embed Kubernetes, and prepare for consistent provisioning.

Resources

  1. Integrating OS builds into your CI/CD pipelines

Automate OS image building and publishing using GitHub Actions or similar CI systems.

Resources

  • Pending
  1. Upgrading your cluster manually

Perform manual upgrades using A/B partitions and Kairos commands. Practice rolling back and verifying upgraded systems.

Resources

  1. Deploying a multi-node cluster

Scale to a multi-node setup by bootstrapping additional Kairos worker nodes. Learn how to use cloud-config to preconfigure joining behavior.

Resources

  1. Upgrading your cluster through Kubernetes

Set up the Kairos Operator to manage in-cluster, declarative upgrades. Apply upgrade plans to roll out updates across multiple nodes in a safe, automated way.

Resources

⏱️ Optional Advanced Topics (time and interest permitting)

  • Build an air-gapped cluster

Mirror container images and OS builds to run a Kubernetes cluster completely offline.

Resources

Combine public cloud and on-prem nodes into a single cluster using Kairos-based images.

Resources

  • Pending

  • PXE/netboot cluster bootstrapping

Use AuroraBoot to provision nodes over the network without local install media i.e. cdrom/usb

Resources

Enable cryptographic boot verification to ensure system integrity at startup.

Resources

Set up a highly available control plane using immutable nodes and external etcd or load balancing.

Resources

Use Kairos mesh networking features to create clusters that auto-discover and join each other.

Resources

Boot Kairos on ARM devices and set up a lightweight edge Kubernetes deployment with real hardware.

Resources