Shell script to automate the k3s multi-nodes for both the master and worker nodes.

k3s-cluster.sh

#!/bin/bash

# Usage: ./install_k3s.sh [master|worker] [master_ip]

if [ "$#" -lt 1 ]; then
    echo "Usage: $0 [master|worker] [master_ip]"
    exit 1
fi

NODE_TYPE=$1
MASTER_IP=$2

if [ "$NODE_TYPE" == "master" ]; then
    # Install k3s as master
    curl -sfL https://get.k3s.io | K3S_KUBECONFIG_MODE="644" sh -

    # Print the join token
    sudo cat /var/lib/rancher/k3s/server/node-token
else
    # Install k3s as worker
    if [ -z "$MASTER_IP" ]; then
        echo "Error: Master IP address is required for worker installation."
        exit 1
    fi

    # Get the join token from the master node
    JOIN_TOKEN=$(ssh user@$MASTER_IP sudo cat /var/lib/rancher/k3s/server/node-token)

    # Install k3s as worker
    curl -sfL https://get.k3s.io | K3S_URL=https://$MASTER_IP:6443 K3S_TOKEN=$JOIN_TOKEN sh -
fi