Note: This guide will help you quickly launch a cluster with default options. The installation section covers in greater detail how K3s can be set up.

New to Kubernetes? The official Kubernetes docs already have some great tutorials outlining the basics here.

Install Script

K3s provides an installation script that is a convenient way to install it as a service on systemd or openrc based systems. This script is available at https://get.k3s.io. To install K3s using this method, just run:

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

After running this installation:

  • The K3s service will be configured to automatically restart after node reboots or if the process crashes or is killed
  • Additional utilities will be installed, including kubectl, crictl, ctr, k3s-killall.sh, and k3s-uninstall.sh
  • A kubeconfig file will be written to /etc/rancher/k3s/k3s.yaml and the kubectl installed by K3s will automatically use it

To install on worker nodes and add them to the cluster, run the installation script with the K3S_URL and K3S_TOKEN environment variables. Here is an example showing how to join a worker node:

curl -sfL https://get.k3s.io | K3S_URL=https://myserver:6443 K3S_TOKEN=mynodetoken sh -

Setting the K3S_URL parameter causes K3s to run in worker mode. The K3s agent will register with the K3s server listening at the supplied URL. The value to use for K3S_TOKEN is stored at /var/lib/rancher/k3s/server/node-token on your server node.

Note: Each machine must have a unique hostname. If your machines do not have unique hostnames, pass the K3S_NODE_NAME environment variable and provide a value with a valid and unique hostname for each node.