04-Demo-Deployment-with-Kubeadm.md

Demo - Deployment with Kubeadm tool

• Take me to Lecture

Apple Silicon

If you have an Apple M1 or M2 (Apple Silicon) machine, then please follow the separate instructions here.

For all other operating systems/hardware including Intel Apple, please remain on this page...

VirtualBox/Vagrant

In this lab, you will build your own 3-node Kubernetes cluster using kubeadm with VirtualBox and Vagrant

Important Note

This lab cannot currently be performed on Apple M1/M2. We are waiting for VirtualBox to release a version that is fully compatible with Apple Silicon.

Changes to Lecture

Since the video was recorded, Kubernetes and Ubuntu have progressed somewhat.

We are now using the latest stable release of Ubuntu - 22.04

Docker is no longer supported as a container driver. Instead we will install the containerd driver and associated tooling.

Lab Instructions

1. Install required software

   • VirtualBox: https://www.virtualbox.org/
   • Vagrant: https://developer.hashicorp.com/vagrant/downloads

2. Clone this repository

   git clone https://github.com/kodekloudhub/certified-kubernetes-administrator-course.git
   cd certified-kubernetes-administrator-course
   

3. Bring up the virtual machines

   vagrant up
   

   This will start 3 virtual machines named

   • kubemaster - where we will install the control plane
   • kubenode01
   • kubenode02

4. Check you can SSH to each VM

   Note: To exit from VM's ssh session, enter exit

   vagrant ssh kubemaster
   

   vagrant ssh kubenode01
   

   vagrant ssh kubenode02
   

5. Initialize the nodes.

   The following steps must be performed on each of the three nodes, so ssh to kubemaster and run the steps, then to kubenode01, then to kubenode02

   1. Configure kernel parameters

      {
      cat <<EOF | sudo tee /etc/modules-load.d/11-k8s.conf
      br_netfilter
      EOF
      
      sudo modprobe br_netfilter
      
      cat <<EOF | sudo tee /etc/sysctl.d/11-k8s.conf
      net.bridge.bridge-nf-call-ip6tables = 1
      net.bridge.bridge-nf-call-iptables = 1
      net.ipv4.ip_forward = 1
      EOF
      
      sudo sysctl --system
      }
      

   2. Install containerd container driver and associated tooling

      {
          sudo apt update
          sudo apt install -y apt-transport-https ca-certificates curl
          sudo curl -fsSLo /usr/share/keyrings/kubernetes-archive-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg
          echo "deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list
          sudo apt-get install -y containerd
          #sudo mkdir -p /opt/cni/bin
          #wget -q --https-only \
          #  https://github.com/containernetworking/plugins/releases/download/v0.8.#6/cni-plugins-linux-amd64-v0.8.6.tgz \
          #  https://github.com/kubernetes-sigs/cri-tools/releases/download/v1.25.0/#crictl-v1.25.0-linux-amd64.tar.gz
          #sudo tar -xzf cni-plugins-linux-amd64-v0.8.6.tgz -C /opt/cni/bin
          #sudo tar -xzf crictl-v1.25.0-linux-amd64.tar.gz -C /usr/local/bin
      }

   3. Install Kubernetes software

      This will install the latest version

      {
      sudo  curl -fsSLo /usr/share/keyrings/kubernetes-archive-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg
      
      echo "deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.
      
      sudo apt update
      
      sudo apt-get install -y kubelet kubeadm kubectl
      sudo apt-mark hold kubelet kubeadm kubectl
      
      # Configure crictl so it doesn't print ugly warning messages
      sudo crictl config \
          --set runtime-endpoint=unix:///run/containerd/containerd.sock \
          --set image-endpoint=unix:///run/containerd/containerd.sock
      }

6. Initialize controlplane node

   1. Get the IP address of the eth0 adapter of the controlplane

      ip addr show dev enp0s8
      

      Take the value printed for inet in the output. This should be:

      192.168.56.11

   2. Create a config file for kubeadm to get settings from

      kind: ClusterConfiguration
      apiVersion: kubeadm.k8s.io/v1beta3
      kubernetesVersion: v1.25.4          # <- At time of writing. Change as appropriate
      controlPlaneEndpoint: 192.168.56.11:6443
      networking:
        serviceSubnet: "10.96.0.0/16"
        podSubnet: "10.244.0.0/16"
        dnsDomain: "cluster.local"
      controllerManager:
        extraArgs:
          "node-cidr-mask-size": "24"
      apiServer:
        extraArgs:
          authorization-mode: "Node,RBAC"
        certSANs:
          - "192.168.56.11"
          - "kubemaster"
          - "kubernetes"
          
      ---
      kind: KubeletConfiguration
      apiVersion: kubelet.config.k8s.io/v1beta1
      cgroupDriver: systemd
      serverTLSBootstrap: true

   3. Run kubeadm init using the IP address determined above for --apiserver-advertise-address

      sudo kubeadm init \
         --apiserver-cert-extra-sans=kubemaster01 \
         --apiserver-advertise-address 192.168.56.11 \
         --pod-network-cidr=10.244.0.0/16
      

      Note the kubeadm join command output at the end of this run. You will require it for the step Initialize the worker nodes below

   4. Set up the default kubeconfig file

      {
      mkdir ~/.kube
      sudo cp /etc/kubernetes/admin.conf ~/.kube/config
      sudo chown vagrant:vagrant ~/.kube/config
      }
      

7. Initialize the worker nodes

   The following steps must be performed on both worker nodes, so ssh to kubenode01 and run the steps, then to kubenode02

   • Paste the kubeadm join command from above step to the command prompt and enter it.