Basic Kubernetes installation snippets

cloud-init.yaml

#cloud-config

users:
  - name: alex
    groups: sudo, docker
    shell: /bin/bash
    lock_passwd: false
    # mkpasswd --method=SHA-512 --rounds=4096
    passwd: "$6$rounds=4096$liX9KRchDIBKuoXt$LqW34rkz2k3yB/MmSPL4SbvGmO0xg7sQKgnwkTAhTV6RjvZAOJS9G4iURlkJS63TRt.ThpE9Thy9G/1.JwXDC0"
    ssh_authorized_keys:
      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDQ1lu+edUae0ND7RzuYe7DnHeakq9WrwZGFgElj2vH4

package_update: true
package_upgrade: false
packages:
  - apt-transport-https

runcmd:
  - |
    tee /etc/modules-load.d/kubernetes.conf <<EOF
    overlay
    br_netfilter
    EOF

  - modprobe overlay
  - modprobe br_netfilter

  - |
    tee /etc/sysctl.d/kubernetes.conf <<EOF
    net.bridge.bridge-nf-call-ip6tables = 1
    net.bridge.bridge-nf-call-iptables = 1
    net.ipv4.ip_forward = 1
    EOF

  - sysctl --system

  - curl -fsSL https://download.docker.com/linux/ubuntu/gpg | gpg --dearmour -o /etc/apt/trusted.gpg.d/docker.gpg
  - apt-add-repository -y "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
  - apt install -y containerd.io

  - containerd config default | tee /etc/containerd/config.toml > /dev/null
  - sed -i 's/SystemdCgroup = false/SystemdCgroup = true/' /etc/containerd/config.toml
  - systemctl restart containerd

  - curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | gpg --dearmour -o /etc/apt/trusted.gpg.d/kubernetes-xenial.gpg
  - apt-add-repository -y "deb http://apt.kubernetes.io/ kubernetes-xenial main"
  - apt install -y kubelet kubeadm kubectl
  - apt-mark hold kubelet kubeadm kubectl

  - kubeadm config images pull

kube-manual-install.sh

# Source tutorials:
# https://www.linuxtechi.com/install-kubernetes-on-ubuntu-22-04/
# https://computingforgeeks.com/install-kubernetes-cluster-ubuntu-jammy/?expand_article=1

tee /etc/modules-load.d/kubernetes.conf <<EOF
overlay
br_netfilter
EOF

modprobe overlay
modprobe br_netfilter

tee /etc/sysctl.d/kubernetes.conf <<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF

sysctl --system

apt update
# Other packages are already installed.
# apt install -y curl gnupg2 software-properties-common apt-transport-https ca-certificates
apt install -y apt-transport-https

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | gpg --dearmour -o /etc/apt/trusted.gpg.d/docker.gpg
apt-add-repository -y "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
apt install -y containerd.io

containerd config default | tee /etc/containerd/config.toml > /dev/null
# https://kubernetes.io/docs/setup/production-environment/container-runtimes/#systemd-cgroup-driver
sed -i 's/SystemdCgroup = false/SystemdCgroup = true/' /etc/containerd/config.toml

systemctl restart containerd
# systemctl status containerd

curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | gpg --dearmour -o /etc/apt/trusted.gpg.d/kubernetes-xenial.gpg
apt-add-repository -y "deb http://apt.kubernetes.io/ kubernetes-xenial main"

apt install -y kubelet kubeadm kubectl
apt-mark hold kubelet kubeadm kubectl

kubeadm config images pull

# FOR MASTER
kubeadm init \
  --service-cidr 10.114.0.0/16 \
  --pod-network-cidr 10.115.0.0/16 \
  --upload-certs

# FOR WORKER
kubeadm join 78.47.170.193:6443 --token ??? \
  --discovery-token-ca-cert-hash ???

# LOCALLY
scp [email protected]:/etc/kubernetes/admin.conf kubectl-admin.conf
export KUBECONFIG=kubectl-admin.conf

wget https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml
sed -i 's|"Network": ".*"|"Network": "10.115.0.0/16"|' kube-flannel.yml
kubectl apply -f kube-flannel.yml




# TODO: cloud init should reboot after done?
# apt upgrade -y
# [ -f /var/run/reboot-required ] && sudo reboot -f
# TODO: apt update after apt-add-repository not needed, right?

Ubuntu 22.04, running on Hetzner, commands executed as root user.