robbinparrish / k3s-single-node-deployment

K3s single-node deployment

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K3S Single Node Deployment.

Setup single node k3s cluster.

Installing k3s.

First find out latest stable release of k3s here. Replace this with LATEST_STABLE_VERSION in below url. Once done then download the binary and install on the system.

# Download and install k3s binary.
wget https://github.com/k3s-io/k3s/releases/download/LATEST_STABLE_VERSION/k3s
mv k3s /usr/bin/k3s
chmod 755 /usr/bin/k3s

# Create symlinks.
ln -sf /usr/bin/k3s /usr/bin/kubectl
ln -sf /usr/bin/k3s /usr/bin/crictl
ln -sf /usr/bin/k3s /usr/bin/ctr

Installing systemd service for k3s.

The Systemd Service File provided here start k3s with default minimal configurations. This may not be correct configuration for all the environment. For detailed info check k3s systemd service configuration.
k3s by-default pull images from docker.io/rancher/ registry. If the docker.io domain is not accessible then k3s will not start. For air-gap installation follow here.

cp configs/k3s.service /etc/systemd/system/k3s.service
chmod 644 /etc/systemd/system/k3s.service
systemctl daemon-reload
systemctl enable --now k3s.service

Configure k3s config.

By default k3s stores config file at /etc/rancher/k3s/k3s.yaml. Following additional configuration requires for kubectl and helm tools to work.

mkdir -p ${HOME}/.kube
cp -a /etc/rancher/k3s/k3s.yaml ${HOME}/.kube/config

Accessing k3s Cluster from other systems.

It may requires to directly access the k3s cluster from some other systems in the network. In this case following additional configuration requires.

# Firewall allow tcp port 6443.
ufw allow 6443/tcp.

On other system, create a file ~/.kube/config. In this file add the contents of the /etc/rancher/k3s/k3s.yaml file. In the ~/.kube/config file replace the loopback ip address to the k3s system ip address.

Helm.

For installing helm follow here

Interacting with k3s cluster