cloud init script with kubernetes, helm, kubectl

cloud-init.yaml

#cloud-config
package_update: true
packages:
  - bash-completion
  - make
  - g++
  - jq
  - fzf
  - kubectx
write_files:
  - path: /root/setup.sh
    permissions: '0755'
    content: |
      #!/bin/bash
      set -e

      ARCH=$(dpkg --print-architecture)

      # Install yq
      wget https://github.com/mikefarah/yq/releases/latest/download/yq_linux_amd64 -O /usr/bin/yq && chmod +x /usr/bin/yq

      # Install kubectl
      wget -q "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/${ARCH}/kubectl"
      install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl
      rm kubectl

      # Enable bash completion for kubectl
      echo "source /usr/share/bash-completion/bash_completion" >> /home/ubuntu/.bashrc
      echo "complete -F __start_kubectl k" >> /home/ubuntu/.bashrc
      echo "alias k=kubectl" >> /home/ubuntu/.bashrc

      # Upgrade k0s
      curl --proto '=https' --tlsv1.2 -sSf https://get.k0s.sh | sudo sh

      # Install kubernetes
      k0s config create > /root/k0s.yaml
      ## we will setup cilium cni
      sed -i 's/provider: kuberouter/provider: custom/' /root/k0s.yaml
      ## disable kubeproxy (maybe not needed but necessary for laaaarge cluster) for cilium handle routing with eBPF
      yq eval '.spec.network.kubeProxy.disabled = true' -i /root/k0s.yaml
      ## Install k8s
      k0s install controller --enable-worker --no-taints -c /root/k0s.yaml
      k0s start
      sleep 120
      mkdir -p /home/ubuntu/.kube/
      k0s kubectl config rename-context Default $HOSTNAME
      yq e ".users[0].name = \"$(hostname)\"" -i /var/lib/k0s/pki/admin.conf
      yq e '.contexts[].context.user = "'$(hostname)'"' -i /var/lib/k0s/pki/admin.conf
      yq e '(.clusters[].name, .contexts[].context.cluster) |= "'$(hostname)'"' -i /var/lib/k0s/pki/admin.conf
      k0s kubeconfig admin > /home/ubuntu/.kube/config
      chown ubuntu:ubuntu /home/ubuntu/.kube/ -R

      # Install Helm
      HELM_RELEASE=$(curl -L -s -H 'Accept: application/json' https://github.com/helm/helm/releases/latest | sed -e 's/.*"tag_name":"\([^"]*\)".*/\1/')
      tar -xvz -C /tmp/ -f <(wget -q -O - https://get.helm.sh/helm-${HELM_RELEASE}-linux-${ARCH}.tar.gz)
      install -o root -g root -m 0755 /tmp/linux-${ARCH}/helm /usr/local/bin/helm

      # Install Cilium CLI
      CILIUM_CLI_VERSION=$(curl -s https://raw.githubusercontent.com/cilium/cilium-cli/main/stable.txt)
      CLI_ARCH=amd64
      if [ "$(uname -m)" = "aarch64" ]; then CLI_ARCH=arm64; fi
      curl -L --fail --remote-name-all https://github.com/cilium/cilium-cli/releases/download/${CILIUM_CLI_VERSION}/cilium-linux-${CLI_ARCH}.tar.gz{,.sha256sum}
      sha256sum --check cilium-linux-${CLI_ARCH}.tar.gz.sha256sum
      sudo tar xzvfC cilium-linux-${CLI_ARCH}.tar.gz /usr/local/bin
      rm cilium-linux-${CLI_ARCH}.tar.gz{,.sha256sum}

      # Install Go
      #wget -q https://go.dev/dl/go1.24.2.linux-${ARCH}.tar.gz
      #tar -xvf go1.24.2.linux-${ARCH}.tar.gz
      #mv go /usr/local
      #echo "export GOROOT=/usr/local/go" >> /etc/bash.bashrc
      #echo "export PATH=\$GOPATH/bin:\$GOROOT/bin:\$PATH" >> /etc/bash.bashrc
      #ln -sf /usr/local/go/bin/go /bin/go

      # Install Docker
      #curl -fsSL get.docker.com -o get-docker.sh
      #sudo sh get-docker.sh
      #sudo systemctl start docker
      #sudo systemctl enable docker

      # Add ubuntu user to docker group
      #sudo usermod -aG docker ubuntu

runcmd:
  - [ bash, /root/setup.sh ]