homelab/active/software_k0s/k0s.md

K0s

Install Single Node Cluster

https://docs.k0sproject.io/v0.11.0/k0s-single-node/

# Allow all traffic in
firewall-cmd --set-default-zone=trusted

# Install k0s cli
curl -sSLf https://get.k0s.sh | sudo sh

# Setup the config
k0s config create > k0s.yaml

# Install single node cluster controller/node
k0s install controller -c k0s.yaml --enable-worker

# Start and enable the service
systemctl enable --now k0scontroller

# Enable bash completion
echo 'source <(k0s completion bash)' >>~/.bashrc
source ~/.bashrc

# Make an admin user
mkdir ~/.kube
k0s kubeconfig create --groups "system:m asters" admin > ~/.kube/config

# Remove the taint that prevents scheduling on the controller
kubectl edit node

Install Multi Node Cluster

https://docs.k0sproject.io/v0.11.0/k0s-multi-node/

Install the controller on the controller machine

# Allow all traffic in
firewall-cmd --set-default-zone=trusted

# Install k0s cli
curl -sSLf https://get.k0s.sh | sudo sh

# Save default config
k0s config create > k0s.yaml

# Install the controller
k0s install controller

# Enable the controller
systemctl enable --now k0scontroller

# Enable bash completion
echo 'source <(k0s completion bash)' >>~/.bashrc
source ~/.bashrc

# Make an admin user (scp ~/.kube/config to your operator machine)
# kubectl config set-context --current --namespace kube-system
mkdir ~/.kube
k0s kubeconfig create --groups "system:masters" admin > ~/.kube/config

# Generate a worker join token
k0s token create --role=worker > worker0-token

Now on the worker machine, install the worker

# Allow all traffic in
firewall-cmd --set-default-zone=trusted

# On the operator, copy the token file from the controller to the worker
scp vm-k0s-controller:worker0-token vm-k0s-worker:token-file

# Install k0s cli
curl -sSLf https://get.k0s.sh | sudo sh

# Join the worker
k0s install worker --token-file token-file

# Start the service
systemctl enable --now k0sworker

# Enable bash completion
echo 'source <(k0s completion bash)' >>~/.bashrc
source ~/.bashrc

Uninstall

systemctl stop k0scontroller
k0s reset
reboot

Install Metallb

https://docs.k0sproject.io/v1.26.0+k0s.0/examples/metallb-loadbalancer/

1. Create a VLAN with a dedicated subnet for Metallb. Disable DHCP.
2. Attach this new VLAN to your worker nodes
3. Assign the worker nodes an address within the created network.
4. Install Metallb. Check active/software_k0s/metallb-configmap.yaml before proceeding.

kubectl apply -f https://raw.githubusercontent.com/metallb/metallb/v0.10.2/manifests/namespace.yaml
kubectl apply -f https://raw.githubusercontent.com/metallb/metallb/v0.10.2/manifests/metallb.yaml

kubectl apply -f active/software_k0s/metallb-configmap.yaml

Uninstall Metallb

kubectl delete -f active/software_k0s/metallb-configmap.yaml

kubectl delete -f https://raw.githubusercontent.com/metallb/metallb/v0.10.2/manifests/metallb.yaml
kubectl delete -f https://raw.githubusercontent.com/metallb/metallb/v0.10.2/manifests/namespace.yaml