Welcome to my highly opinionated template for deploying a single Kubernetes (k3s) cluster with Ansible and using Flux to manage its state.
The goal of this project is to make it easy for people interested in learning Kubernetes to deploy a basic cluster at home and become familiar with the GitOps tool Flux.
This template implements Flux in a way that promotes legibility and ease of use for those who are new (or relatively new) to the technology and GitOps in general. It assumes a typical homelab setup: namely, a single "home prod" cluster running mostly third-party apps.
- Automated, reproducible, customizable setup through Ansible templates and playbooks
- Opinionated implementation of Flux with strong community support
- Encrypted secrets thanks to SOPS and Age
- Web application firewall thanks to Cloudflare Tunnel
- SSL certificates thanks to Cloudflare and cert-manager
- HA control plane capability thanks to kube-vip
- Next-gen networking thanks to Cilium
- A Renovate-ready repository
- Integrated GitHub Actions
... and more!
Before we get started everything below must be taken into consideration, you must...
- bring a positive attitude and be ready to learn and fail a lot. The more you fail, the more you can learn from.
- run the cluster on bare metal machines or VMs within your home network β this is NOT designed for cloud environments.
- have Debian 12 freshly installed on 1 or more AMD64/ARM64 bare metal machines or VMs. Each machine will be either a control node or a worker node in your cluster.
- give your nodes unrestricted internet access β air-gapped environments won't work.
- have a domain you can manage on Cloudflare.
- be willing to commit encrypted secrets to a public GitHub repository.
- have a DNS server that supports split DNS (e.g. Pi-Hole) deployed somewhere outside your cluster ON your home network.
π k3s default behaviour is that all nodes are able to run workloads, including contol nodes. Worker nodes are therefore optional.
π If you have 3 or more nodes it is strongly recommended to make 3 of them control nodes for a highly available control plane.
π Ideally you will run the cluster on bare metal machines. If you intend to run your cluster on Proxmox VE, my thoughts and recommendations about that are documented here.
Role | Cores | Memory | System Disk |
---|---|---|---|
Control | 4 (6*) | 8GB (24GB*) | 100GB (500GB*) SSD/NVMe |
Worker | 4 (6*) | 8GB (24GB*) | 100GB (500GB*) SSD/NVMe |
* recommended |
-
Download the latest stable release of Debian from here, then follow this guide to get it installed. Deviations from the guide:
Choose "Guided - use entire disk" Choose "All files in one partition" Delete Swap partition Uncheck all Debian desktop environment options
-
[Post install] Remove CD/DVD as apt source
su - sed -i '/deb cdrom/d' /etc/apt/sources.list apt update exit
-
[Post install] Enable sudo for your non-root user
su - apt update apt install -y sudo usermod -aG sudo ${username} echo "${username} ALL=(ALL) NOPASSWD:ALL" | tee /etc/sudoers.d/${username} exit newgrp sudo sudo apt update
-
[Post install] Add SSH keys (or use
ssh-copy-id
on the client that is connecting)π First make sure your ssh keys are up-to-date and added to your github account as instructed.
mkdir -m 700 ~/.ssh sudo apt install -y curl curl https://github.com/${github_username}.keys > ~/.ssh/authorized_keys chmod 600 ~/.ssh/authorized_keys
π If you choose to use a Raspberry Pi 4 for the cluster, it is recommended to have an 8GB model. Most important is to boot from an external SSD/NVMe rather than an SD card. This is supported natively, however if you have an early model you may need to update the bootloader first.
π Be sure to check the power requirements if using a PoE Hat and a SSD/NVMe dongle.
-
Download the latest stable release of Debian from here. Do not use Raspbian or DietPi or any other flavor Linux OS.
-
Flash the image onto an SSD/NVMe drive.
-
Re-mount the drive to your workstation and then do the following (per the official documentation):
Open 'sysconf.txt' in a text editor and save it upon updating the information below - Change 'root_authorized_key' to your desired public SSH key - Change 'root_pw' to your desired root password - Change 'hostname' to your desired hostname
-
Connect SSD/NVMe drive to the Raspberry Pi 4 and power it on.
-
[Post install] SSH into the device with the
root
user and then create a normal user account withadduser ${username}
-
[Post install] Follow steps 3 and 4 from Debian for AMD64.
-
[Post install] Install
python3
which is needed by Ansible.sudo apt install -y python3
Once you have installed Debian on your nodes, there are 6 stages to getting a Flux-managed cluster up and runnning.
-
Create a new public repository by clicking the big green "Use this template" button at the top of this page.
-
Clone your new repo to you local workstation and
cd
into it.
π All commands during the setup process are run on your local workstation within your repository directory
π Let's get the required workstation tools installed and configured.
-
Install the most recent version of task
π See the task installation docs for other platforms
# Brew brew install go-task
-
Install the most recent version of direnv
π See the direnv installation docs for other platforms
π After installing
direnv
be sure to hook it into your shell and after that is done rundirenv allow
while in your repos directory.# Brew brew install direnv
-
Setup a Python virual env and install Ansible by running the following task command.
π This commands requires Python 3.8+ to be installed
# Platform agnostic task deps
-
Install the required tools: age, flux, cloudflared, kubectl, sops
# Brew task brew:deps
π Both bootstrap/vars/config.yaml
and bootstrap/vars/addons.yaml
files contain necessary information that is needed by bootstrap process.
-
Generate the
bootstrap/vars/config.yaml
andbootstrap/vars/addons.yaml
configuration files.task init
-
Setup Age private / public key
π Using SOPS with Age allows us to encrypt secrets and use them in Ansible and Flux.
2a. Create a Age private / public key (this file is gitignored)
age-keygen -o age.key
2b. Fill out the appropriate vars in
bootstrap/vars/config.yaml
-
Create Cloudflare API Token
π To use
cert-manager
with the Cloudflare DNS challenge you will need to create a API Token.3a. Head over to Cloudflare and create a API Token by going here.
3b. Under the
API Tokens
section click the blueCreate Token
button.3c. Click the blue
Use template
button for theEdit zone DNS
template.3d. Name your token something like
home-kubernetes
3e. Under
Permissions
, click+ Add More
and add each permission below:Zone - DNS - Edit Account - Cloudflare Tunnel - Read
3f. Limit the permissions to a specific account and zone resources.
3g. Fill out the appropriate vars in
bootstrap/vars/config.yaml
-
Create Cloudflare Tunnel
π To expose services to the internet you will need to create a Cloudflare Tunnel.
4a. Authenticate cloudflared to your domain
cloudflared tunnel login
4b. Create the tunnel
cloudflared tunnel create k8s
4c. In the
~/.cloudflared
directory there will be a json file with details you need. Ignore thecert.pem
file.4d. Fill out the appropriate vars in
bootstrap/vars/config.yaml
-
Complete filling out the rest of the
bootstrap/vars/config.yaml
configuration file.5a. Ensure
bootstrap_acme_production_enabled
is set tofalse
.5b. [Optional] Update
bootstrap/vars/addons.yaml
and enable applications you would like included. -
Once done run the following command which will verify and generate all the files needed to continue.
task configure
π The configure task will create a ./ansible
directory and the following directories under ./kubernetes
.
π kubernetes # Kubernetes cluster defined as code
ββπ bootstrap # Flux installation (not tracked by Flux)
ββπ flux # Main Flux configuration of repository
ββπ apps # Apps deployed into the cluster grouped by namespace
π Here we will be running an Ansible playbook to prepare your nodes for running a Kubernetes cluster.
-
Ensure you are able to SSH into your nodes from your workstation using a private SSH key without a passphrase (for example using a SSH agent). This lets Ansible interact with your nodes.
-
Verify Ansible can view your config
task ansible:list
-
Verify Ansible can ping your nodes
task ansible:ping
-
Run the Ansible prepare playbook (nodes wil reboot when done)
task ansible:prepare
π Here we will be running a Ansible Playbook to install k3s with this Ansible galaxy role. If you run into problems, you can run task ansible:nuke
to destroy the k3s cluster and start over from this point.
-
Verify Ansible can view your config
task ansible:list
-
Verify Ansible can ping your nodes
task ansible:ping
-
Install k3s with Ansible
task ansible:install
-
Verify the nodes are online
π If this command fails you likely haven't configured
direnv
as mentioned previously in the guide.kubectl get nodes -o wide # NAME STATUS ROLES AGE VERSION # k8s-0 Ready control-plane,etcd,master 1h v1.27.3+k3s1 # k8s-1 Ready worker 1h v1.27.3+k3s1
-
The
kubeconfig
for interacting with your cluster should have been created in the root of your repository.
π Here we will be installing flux after some quick bootstrap steps.
-
Verify Flux can be installed
flux check --pre # βΊ checking prerequisites # β kubectl 1.27.3 >=1.18.0-0 # β Kubernetes 1.27.3+k3s1 >=1.16.0-0 # β prerequisites checks passed
-
Push you changes to git
π Verify all the
*.sops.yaml
and*.sops.yaml
files under the./ansible
, and./kubernetes
directories are encrypted with SOPSgit add -A git commit -m "Initial commit :rocket:" git push
-
Install Flux and sync the cluster to the Git repository
task cluster:install # namespace/flux-system configured # customresourcedefinition.apiextensions.k8s.io/alerts.notification.toolkit.fluxcd.io created # ...
-
Verify Flux components are running in the cluster
kubectl -n flux-system get pods -o wide # NAME READY STATUS RESTARTS AGE # helm-controller-5bbd94c75-89sb4 1/1 Running 0 1h # kustomize-controller-7b67b6b77d-nqc67 1/1 Running 0 1h # notification-controller-7c46575844-k4bvr 1/1 Running 0 1h # source-controller-7d6875bcb4-zqw9f 1/1 Running 0 1h
Mic check, 1, 2 - In a few moments applications should be lighting up like Christmas in July π
-
Output all the common resources in your cluster.
π Feel free to use the provided cluster tasks for validation of cluster resources or continue to get familiar with the
kubectl
andflux
CLI tools.task cluster:resources
-
β οΈ It might takecert-manager
awhile to generate certificates, this is normal so be patient. -
π Congratulations if all goes smooth you will have a Kubernetes cluster managed by Flux and your Git repository is driving the state of your cluster.
-
π§ Now it's time to pause and go get some motel motor oil β and admire you made it this far!
The external-dns
application created in the networking
namespace will handle creating public DNS records. By default, echo-server
and the flux-webhook
are the only subdomains reachable from the public internet. In order to make additional applications public you must set set the correct ingress class name and ingress annotations like in the HelmRelease for echo-server
.
k8s_gateway
will provide DNS resolution to external Kubernetes resources (i.e. points of entry to the cluster) from any device that uses your home DNS server. For this to work, your home DNS server must be configured to forward DNS queries for ${bootstrap_cloudflare_domain}
to ${bootstrap_k8s_gateway_addr}
instead of the upstream DNS server(s) it normally uses. This is a form of split DNS (aka split-horizon DNS / conditional forwarding).
π Below is how to configure a Pi-hole for split DNS. Other platforms should be similar.
-
Apply this file on the server
# /etc/dnsmasq.d/99-k8s-gateway-forward.conf server=/${bootstrap_cloudflare_domain}/${bootstrap_k8s_gateway_addr}
-
Restart dnsmasq on the server.
-
Query an internal-only subdomain from your workstation:
dig @${home-dns-server-ip} echo-server.${bootstrap_cloudflare_domain}
. It should resolve to${bootstrap_internal_ingress_addr}
.
If you're having trouble with DNS be sure to check out these two GitHub discussions: Internal DNS and Pod DNS resolution broken.
... Nothing working? That is expected, this is DNS after all!
By default this template will deploy a wildcard certificate using the Let's Encrypt staging environment, which prevents you from getting rate-limited by the Let's Encrypt production servers if your cluster doesn't deploy properly (for example due to a misconfiguration). Once you are sure you will keep the cluster up for more than a few hours be sure to switch to the production servers as outlined in config.yaml
.
π You will need a production certificate to reach internet-exposed applications through cloudflared
.
By default Flux will periodically check your git repository for changes. In order to have Flux reconcile on git push
you must configure Github to send push
events.
-
Obtain the webhook path
π Hook id and path should look like
/hook/12ebd1e363c641dc3c2e430ecf3cee2b3c7a5ac9e1234506f6f5f3ce1230e123
kubectl -n flux-system get receiver github-receiver -o jsonpath='{.status.webhookPath}'
-
Piece together the full URL with the webhook path appended
https://flux-webhook.${bootstrap_cloudflare_domain}/hook/12ebd1e363c641dc3c2e430ecf3cee2b3c7a5ac9e1234506f6f5f3ce1230e123
-
Navigate to the settings of your repository on Github, under "Settings/Webhooks" press the "Add webhook" button. Fill in the webhook url and your
bootstrap_flux_github_webhook_token
secret and save.
Renovate is a tool that automates dependency management. It is designed to scan your repository around the clock and open PRs for out-of-date dependencies it finds. Common dependencies it can discover are Helm charts, container images, GitHub Actions, Ansible roles... even Flux itself! Merging a PR will cause Flux to apply the update to your cluster.
To enable Renovate, click the 'Configure' button over at their Github app page and select your repository. Renovate creates a "Dependency Dashboard" as an issue in your repository, giving an overview of the status of all updates. The dashboard has interactive checkboxes that let you do things like advance scheduling or reattempt update PRs you closed without merging.
The base Renovate configuration in your repository can be viewed at .github/renovate.json5. By default it is scheduled to be active with PRs every weekend, but you can change the schedule to anything you want, or remove it if you want Renovate to open PRs right away. It is also configured to automerge some updates.
Below is a general guide on trying to debug an issue with an resource or application. For example, if a workload/resource is not showing up or a pod has started but in a CrashLoopBackOff
or Pending
state.
-
Start by checking all Flux Kustomizations & Git Repository & OCI Repository and verify they are healthy.
flux get sources oci -A flux get sources git -A flux get ks -A
-
Then check all the Flux Helm Releases and verify they are healthy.
flux get hr -A
-
Then check the if the pod is present.
kubectl -n <namespace> get pods -o wide
-
Then check the logs of the pod if its there.
kubectl -n <namespace> logs <pod-name> -f # or stern -n <namespace> <fuzzy-name>
-
If a resource exists try to describe it to see what problems it might have.
kubectl -n <namespace> describe <resource> <name>
-
Check the namespace events
kubectl -n <namespace> get events --sort-by='.metadata.creationTimestamp'
Resolving problems that you have could take some tweaking of your YAML manifests in order to get things working, other times it could be a external factor like permissions on NFS. If you are unable to figure out your problem see the help section below.
- Make a post in this repository's Github Discussions.
- Start a thread in the
support
orflux-cluster-template
channel in the k8s@home Discord server.
The cluster is your oyster (or something like that). Below are some optional considerations you might want to review.
To browse or get ideas on applications people are running, community member @whazor created this website as a creative way to search Flux HelmReleases across Github.
The included CSI (local-path-provisioner
) is a great start for storage but soon you might find you need more features like replicated block storage, or to connect to a NFS/SMB/iSCSI server. If you need any of those features be sure to check out the projects like rook-ceph, longhorn, openebs, democratic-csi, csi-driver-nfs,
and synology-csi.
Authenticating Flux to your git repository has a couple benefits like using a private git repository and/or using the Flux Image Automation Controllers.
By default this template only works on a public Github repository, it is advised to keep your repository public.
The benefits of a public repository include:
- Debugging or asking for help, you can provide a link to a resource you are having issues with.
- Adding a topic to your repository of
k8s-at-home
to be included in the k8s-at-home-search. This search helps people discover different configurations of Helm charts across others Flux based repositories.
Expand to read guide on adding Flux SSH authentication
-
Generate new SSH key:
ssh-keygen -t ecdsa -b 521 -C "github-deploy-key" -f ./kubernetes/bootstrap/github-deploy.key -q -P ""
-
Paste public key in the deploy keys section of your repository settings
-
Create sops secret in
./kubernetes/bootstrap/github-deploy-key.sops.yaml
with the contents of:apiVersion: v1 kind: Secret metadata: name: github-deploy-key namespace: flux-system stringData: # 3a. Contents of github-deploy-key identity: | -----BEGIN OPENSSH PRIVATE KEY----- ... -----END OPENSSH PRIVATE KEY----- # 3b. Output of curl --silent https://api.github.com/meta | jq --raw-output '"github.com "+.ssh_keys[]' known_hosts: | github.com ssh-ed25519 ... github.com ecdsa-sha2-nistp256 ... github.com ssh-rsa ...
-
Encrypt secret:
sops --encrypt --in-place ./kubernetes/bootstrap/github-deploy-key.sops.yaml
-
Apply secret to cluster:
sops --decrypt ./kubernetes/bootstrap/github-deploy-key.sops.yaml | kubectl apply -f -
-
Update
./kubernetes/flux/config/cluster.yaml
:apiVersion: source.toolkit.fluxcd.io/v1beta2 kind: GitRepository metadata: name: home-kubernetes namespace: flux-system spec: interval: 10m # 6a: Change this to your user and repo names url: ssh://git@github.com/$user/$repo ref: branch: main secretRef: name: github-deploy-key
-
Commit and push changes
-
Force flux to reconcile your changes
flux reconcile -n flux-system kustomization cluster --with-source
-
Verify git repository is now using SSH:
flux get sources git -A
-
Optionally set your repository to Private in your repository settings.
Big shout out to all the contributors, sponsors and everyone else who has helped on this project.