K3s HA running in AWS

Single server clusters can meet a variety of use cases, but for environments where uptime of the Kubernetes control plane is critical, you can run K3s in an HA configuration. An HA K3s cluster is comprised of:

• Two or more server nodes that will serve the Kubernetes API and run other control plane services
• An external datastore (as opposed to the embedded SQLite datastore used in single-server setups)

Requirements

• Create and config 3 Ec2 instances (Linux machine).
• Experience in Kubernetes
• Desire to learn about k3s

Server node

Run command

curl -sfL https://get.k3s.io | sh -s — — write-kubeconfig-mode 644

Get the server token running the command

cat /var/lib/rancher/k3s/server/node-token

Workers nodes

• Create 2 new servers, those servers will be called workers .

• Connect to worker-1

Create the env variables:

K3S_URL=https://myserver:6443 (Public URL from your server)
K3S_TOKEN=mytoken

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=mytoken sh -

Go to worker-2 and repeat the process.

Verify the nodes

Go to the server node and run:

k3s kubectl get node

You must see the node server and 2 workers working and running.

Create your local Kube config

Keep in the server node and run:

cat /etc/rancher/k3s/k3s.yaml

copy the result.

In your local machine, run

nano ~/.kube/config

and paste the result got from the server node.

Done, you can interact with your cluster from the local machine. You are ready to apply for your first deployment in K3s. Good luck