Add k3s installation to base Packer image

Install k3s (lightweight Kubernetes) in base AMI without auto-starting.
Services can be started manually when needed.

Author: rustyrazorblade

packer/base/base.pkr.hcl

@@ -93,6 +93,11 @@ build {
     script = "install/install_docker.sh"
   }
 
+  # install k3s (disabled, not auto-started)
+  provisioner "shell" {
+    script = "install/install_k3s.sh"
+  }
+
   provisioner "shell" {
     inline = [
       "sudo apt install openjdk-8-jdk openjdk-8-dbg openjdk-11-jdk openjdk-11-dbg openjdk-17-jdk openjdk-17-dbg -y",

packer/base/install/install_k3s.sh

@@ -0,0 +1,34 @@
+#!/bin/bash
+
+set -x
+
+# Install k3s on Ubuntu 22.04
+# k3s will be installed but NOT enabled or started automatically
+# Services can be started manually when needed
+
+# Download and run k3s installer
+# Using the latest stable until something breaks horribly forcing me to pin versions.
+#
+# INSTALL_K3S_SKIP_ENABLE: Don't enable systemd services
+# INSTALL_K3S_SKIP_START: Don't start services after installation
+curl -sfL https://get.k3s.io | \
+  INSTALL_K3S_SKIP_ENABLE=true \
+  INSTALL_K3S_SKIP_START=true \
+  sh -
+
+# Create kubectl symlink for convenience
+sudo ln -sf /usr/local/bin/k3s /usr/local/bin/kubectl
+
+# Create kubeconfig directory structure
+sudo mkdir -p /etc/rancher/k3s
+
+# Set up permissions for k3s config directory
+sudo chmod 755 /etc/rancher/k3s
+
+# Verify installation (just check binary exists, don't start service)
+k3s --version
+kubectl version --client
+
+echo "k3s installation complete. Services are installed but NOT enabled."
+echo "To start k3s server: sudo systemctl start k3s"
+echo "To start k3s agent: sudo systemctl start k3s-agent"