Install Kubernetes v1.32 worker node

install-k8s-1.32.sh

#!/bin/bash
set -e

MASTER=false
for arg in "$@"; do
  if [[ "$arg" == "--master" ]]; then
    MASTER=true
    break
  fi
done

echo "[0/8] Prepare bash"
echo 'export PATH=$PATH:/usr/sbin' >> /home1/irteamsu/.bashrc
echo 'export PATH=$PATH:/usr/local/bin' >> /home1/irteamsu/.bashrc
echo 'alias k=kubectl' >> /home1/irteamsu/.bashrc
echo 'complete -F __start_kubectl k' >> /home1/irteamsu/.bashrc
echo 'source <(kubectl completion bash)' >> /home1/irteamsu/.bashrc
echo 'source <(kubeadm completion bash)' >> /home1/irteamsu/.bashrc

echo "[1/8] Disabling swap"
swapoff -a
sed -i '/swap/d' /etc/fstab

echo "[2/8] Loading kernel modules"
cat <<EOF | tee /etc/modules-load.d/k8s.conf
overlay
br_netfilter
EOF

modprobe overlay
modprobe br_netfilter

echo "[3/8] Setting sysctl params"
cat <<EOF | tee /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-iptables  = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv4.ip_forward                 = 1
EOF
sysctl --system

echo "[4/8] Installing containerd"
dnf install -y yum-utils device-mapper-persistent-data lvm2
dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo
dnf install -y containerd.io

mkdir -p /etc/containerd
containerd config default > /etc/containerd/config.toml
sed -i 's/SystemdCgroup = false/SystemdCgroup = true/' /etc/containerd/config.toml

systemctl enable --now containerd

echo "[5/8] Adding Kubernetes repo"
cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://pkgs.k8s.io/core:/stable:/v1.31/rpm/
enabled=1
gpgcheck=1
gpgkey=https://pkgs.k8s.io/core:/stable:/v1.31/rpm/repodata/repomd.xml.key
EOF

echo "[6/8] Installing kubelet, kubeadm, kubectl"
dnf install -y kubelet kubeadm kubectl
systemctl enable --now kubelet

echo "[7/8] Setting SELinux to permissive (if not already disabled)"
if selinuxenabled; then
  sudo setenforce 0
  sudo sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
else
  echo "SELinux is already disabled — skipping"
fi

if [ "$MASTER" = true ]; then
  sudo kubeadm init --pod-network-cidr=10.244.0.0/16

  mkdir -p /home1/irteamsu/.kube
  sudo cp -f /etc/kubernetes/admin.conf /home1/irteamsu/.kube/config
  sudo chown irteamsu:irteamsu /home1/irteamsu/.kube/config

  export KUBECONFIG=/home1/irteamsu/.kube/config
  kubectl apply -f https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml

  echo "[8/8] ✅ Master node initialized!"
  kubeadm token create --print-join-command
else
  echo ""
  echo "[8/8] ✅ Kubernetes worker node is ready."
  echo "👉 Once the master is initialized, join it using the token from the master node:"
  echo "   kubeadm join <master-ip>:6443 --token <token> --discovery-token-ca-cert-hash sha256:<hash>"
fi