Homelab 1 - Setting up K3s

This series of posts will detail the setup of my homelab. It goes into the technical details of how I setup a single-node K3s Kubernetes cluster using cdk8s and Deno to generate all of the required YAML manifests. This is a practical deployment with:

• Automated backups
• Monitoring and alerting
• Automated deployments
• Automatic image/chart upgrades
• Support for GPU acceleration
• Secure secrets with 1Password
• Secure remote access through Tailscale
• Direct access for game servers and certain protocols like mDNS

Table of Contents

• Background
• Operating System
• Kubernetes
• Bootstrapping
• Conclusion

Background

I’ve had a homelab for around a decade. The hardware itself has gone from repurposed parts in college (a Core Duo served me very well from 2017-2022) to a very beefy server today:

• Intel Core i9-14900K 3.2 GHz 24-Core
• 2 x Corsair Vengeance 32 GB (2 x 16 GB) DDR5-5600
• Samsung 990 Pro 4 TB
• 5 x Seagate BarraCuda 4 TB 5400 RPM

(The full build is on PCPartPicker)

Over the years I’ve tried quite a few ways to manage it:

• Manually installing everything without any automation
• Artisinal, hand-written bash scripts
• Ansible
• Docker Compose

Those methods were mostly informed by what I was wanting to learn. That trend hasn’t changed with my move to Kubernetes. I had no experience with K8s back in December, and today I use it to manage my homelab quite successfully. Kubernetes is overkill for a homelab, but it does provide a great learning environment for me where the consequences are relatively low (as long as my backups keep working).

I name each iteration of my server so that I can disambiguate between references of older installations. Previously I named my servers after Greek/Roman gods, but now I’m using the names of famous computer scientists. The name of the latest iteration is “lamport”, named after Leslie Lamport who is known for his work in distributed systems.

Operating System

Because I was planning on running everything in Kubernetes, I considered using Talos rather than my usual choice of Ubuntu Server. Talos is an immutable Linux distribution with support for Kubernetes baked-in. I ultimately didn’t choose Talos because at the time required a dedicated drive for the operating system, meaning my entire 4TB SSD would be taken up by Talos.

I ultimately chose Ubuntu Server which has served me well for years despite the community seeming to be unhappy with some of the recent choices by Canonical. I didn’t do anything special for my installation other than setting up my RAID 5 array with mdadm and fstab.

Kubernetes

Similar to how there are multiple flavors of Linux distributions, there are many distributios of Kubernetes. I chose to use K3s since it has a reputation of being lightweight, easy-to-use, and stable.

You can configure K3s by creating a file at /etc/rancher/k3s/config.yaml. There are some options that cannot be changed after K3s is installed. The one most relevant to me is IPv6 support. Be sure to look through the configuration options.

Installation is straightforward:

$ curl -sfL https://get.k3s.io | sh -

And… that’s it! You now have a Kubernetes cluster running on your machine. You can use kubectl to interact with your cluster. I also use Aptakube on my MacBook when I want a GUI for monitoring my cluster.

I use Tailscale to securely access my homelab. Tailscale is a Wireguard-based VPN that’s, quite honestly, fun to use. You can use your favorite VPN to access your homelab, or if you’re brave you can expose it to the public internet.

Credentials for your cluster are stored at /etc/rancher/k3s/k3s.yaml. You can copy this file to ~/.kube/config on your local machine to use kubectl. Note: you’ll also need to change the server field to point to the address of your server.

Bootstrapping

This does require a small amount of manual bootstrapping, which I describe in my repository README. Whenever I setup a new cluster/node, I need to:

• Install ArgoCD: kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml
• Create a secrets to access my 1Password vaults
• Deploy the manifests in this repo: kubectl apply -f cdk8s/dist/apps.k8s.yaml

I’ve recreated my cluster a couple of times and I’ve been very pleased with how easy it is to get everything back up and running. It takes me just a few minutes from installing K3s to having all of my services back up and running.

Conclusion

I’ve shown how I setup my cluster with K3s. In future posts I’ll cover:

• Using Deno and cdk8s to generate manifests
• Automating deployments with ArgoCD
• Ingress with HTTPS and Tailscale
• Direct connections to pods
• mDNS
• Persistent volumes
• Backups
• Monitoring
• Helm, Kustomize, and operators
• Keeping things up-to-date