Kubernetes Cluster for CKAD/CKA practice with Vagrant + VirtualBox

vagrant + virtualbox + kubernetes

# Directory structure:
kubernetes-lab
  Vagrantfil
  bootstrap.sh
  master.sh
  worker.sh
──────────────────────────────────────────────── cat Vagrantfile ────────────────────────────────────────────────
# -*- mode: ruby -*-
# vi: set ft=ruby :
ENV['VAGRANT_NO_PARALLEL'] = 'yes'
Vagrant.configure(2) do |config|
  config.vm.provision "shell", path: "bootstrap.sh"
  config.vm.synced_folder ".", "/vagrant", type: "virtualbox"
  # Kubernetes Master Server
  config.vm.define "kmaster" do |node|
    node.vm.box               = "generic/ubuntu2004"
    node.vm.box_check_update  = false
    node.vm.box_version       = "3.3.0"
    node.vm.hostname          = "kmaster.k8s.com"
    node.vm.network "private_network", ip: "192.168.56.100"
    node.vm.provider :virtualbox do |v|
      v.name    = "kmaster"
      v.memory  = 2048
      v.cpus    =  2
    end
    node.vm.provision "shell", path: "master.sh"
  end
  # Kubernetes Worker Nodes
  NodeCount = 2
  (1..NodeCount).each do |i|
    config.vm.define "kworker#{i}" do |node|
      node.vm.box               = "generic/ubuntu2004"
      node.vm.box_check_update  = false
      node.vm.box_version       = "3.3.0"
      node.vm.hostname          = "kworker#{i}.k8s.com"
      node.vm.network "private_network", ip: "192.168.56.10#{i}"
      node.vm.provider :virtualbox do |v|
        v.name    = "kworker#{i}"
        v.memory  = 2048
        v.cpus    = 2
      end
      node.vm.provision "shell", path: "worker.sh"
    end
  end
end
─────────────────────────────────────────────── cat bootstrap.sh ────────────────────────────────────────────────
#!/bin/bash

## !IMPORTANT ##
#
## This script is tested only in the generic/ubuntu2004 Vagrant box
## If you use a different version of Ubuntu or a different Ubuntu Vagrant box test this again
#

echo "[TASK 0] Setting TimeZone"
timedatectl set-timezone Asia/Shanghai

echo "[TASK 1] Setting DNS"
cat >/etc/systemd/resolved.conf <<EOF
[Resolve]
DNS=8.8.8.8
FallbackDNS=223.5.5.5
EOF
systemctl daemon-reload
systemctl restart systemd-resolved.service
mv /etc/resolv.conf /etc/resolv.conf.bak
ln -s /run/systemd/resolve/resolv.conf /etc/resolv.conf

echo "[TASK 2] Setting Ubuntu System Mirrors"
cat >/etc/apt/sources.list<<EOF
deb http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
EOF
apt update -qq >/dev/null 2>&1

echo "[TASK 3] Disable and turn off SWAP"
sed -i '/swap/d' /etc/fstab
swapoff -a

echo "[TASK 4] Stop and Disable firewall"
systemctl disable --now ufw >/dev/null 2>&1

echo "[TASK 5] Enable and Load Kernel modules"
cat >>/etc/modules-load.d/containerd.conf<<EOF
overlay
br_netfilter
EOF
modprobe overlay
modprobe br_netfilter

echo "[TASK 6] Add Kernel settings"
cat >>/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 >/dev/null 2>&1

echo "[TASK 7] Install containerd runtime"
apt install -qq -y containerd apt-transport-https >/dev/null 2>&1
mkdir /etc/containerd
containerd config default > /etc/containerd/config.toml

sed -i "s#k8s.gcr.io#registry.aliyuncs.com/k8sxio#g"  /etc/containerd/config.toml
sed -i 's#SystemdCgroup = false#SystemdCgroup = true#g' /etc/containerd/config.toml
sed -i "s#https://registry-1.docker.io#https://registry.cn-hangzhou.aliyuncs.com#g"  /etc/containerd/config.toml
sed -i '/\[plugins\.\"io\.containerd\.grpc\.v1\.cri\"\.registry\.mirrors\]/ a\\ \ \ \ \ \ \ \ [plugins."io.containerd.grpc.v1.cri".registry.mirrors."docker.io"]\n\ \ \ \ \ \ \ \ \ \ endpoint = ["https://bqr1dr1n.mirror.aliyuncs.com"]' /etc/containerd/config.toml
sed -i '/\[plugins\.\"io\.containerd\.grpc\.v1\.cri\"\.registry\.mirrors\]/ a\\ \ \ \ \ \ \ \ [plugins."io.containerd.grpc.v1.cri".registry.mirrors."k8s.gcr.io"]\n\ \ \ \ \ \ \ \ \ \ endpoint = ["https://registry.aliyuncs.com/k8sxio"]' /etc/containerd/config.toml
systemctl daemon-reload
systemctl enable containerd --now >/dev/null 2>&1
systemctl restart containerd

echo "[TASK 8] Add apt repo for kubernetes"
curl -s https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | apt-key add - 
cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main
EOF
apt update -qq >/dev/null 2>&1

echo "[TASK 9] Install Kubernetes components (kubeadm, kubelet and kubectl)"
apt install -qq -y kubeadm=1.22.0-00 kubelet=1.22.0-00 kubectl=1.22.0-00 >/dev/null 2>&1
crictl config runtime-endpoint /run/containerd/containerd.sock
crictl config image-endpoint /run/containerd/containerd.sock

echo "[TASK 10] Enable ssh password authentication"
sed -i 's/^PasswordAuthentication .*/PasswordAuthentication yes/' /etc/ssh/sshd_config
echo 'PermitRootLogin yes' >> /etc/ssh/sshd_config
systemctl reload sshd

echo "[TASK 11] Set root password"
echo -e "kubeadmin\nkubeadmin" | passwd root >/dev/null 2>&1
echo "export TERM=xterm" >> /etc/bash.bashrc

echo "[TASK 12] Update /etc/hosts file"
cat >>/etc/hosts<<EOF
192.168.56.100   kmaster.k8s.com     kmaster
192.168.56.101   kworker1.k8s.com    kworker1
192.168.56.102   kworker2.k8s.com    kworker2
EOF
───────────────────────────────────────────────── cat master.sh ─────────────────────────────────────────────────
#!/bin/bash
echo "[TASK 1] Pull required containers"
kubeadm config images list | grep -v 'coredns' | sed 's#k8s.gcr.io#ctr images pull registry.aliyuncs.com\/k8sxio#g' > images.sh
cat >> images.sh<<EOF
ctr -n k8s.io images pull docker.io/v5cn/coredns:v1.8.4
ctr -n k8s.io images tag docker.io/v5cn/coredns:v1.8.4 registry.aliyuncs.com/k8sxio/coredns:v1.8.4
EOF
chmod +x images.sh && ./images.sh >/dev/null 2>&1

echo "[TASK 2] Initialize Kubernetes Cluster"
kubeadm init \
  --apiserver-advertise-address=192.168.56.100 \
  --control-plane-endpoint=kmaster.k8s.com \
  --kubernetes-version v1.22.0 \
  --image-repository registry.aliyuncs.com/k8sxio \
  --pod-network-cidr=192.168.0.0/16 > /root/kubeinit.log 2>/dev/null

echo "[TASK 3] Deploy Calico network"
kubectl --kubeconfig=/etc/kubernetes/admin.conf create -f https://docs.projectcalico.org/v3.18/manifests/calico.yaml >/dev/null 2>&1

echo "[TASK 4] Generate and save cluster join command to /joincluster.sh"
kubeadm token create --print-join-command > /root/joincluster.sh 2>/dev/null
───────────────────────────────────────────────── cat worker.sh ─────────────────────────────────────────────────
#!/bin/bash
echo "[TASK 1] Join node to Kubernetes Cluster"
apt install -qq -y sshpass >/dev/null 2>&1
sshpass -p "kubeadmin" scp -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no kmaster.k8s.com:/root/joincluster.sh /root/joincluster.sh 2>/dev/null
bash /root/joincluster.sh >/dev/null 2>&1