apple-silicon

Installing Kubernetes the kubeadm way on Apple Silicon

In here is the setup specific to Apple Silicon (M1/M2) Macs. VirtualBox currently does not have good support for these Macs, therefore we will create the Ubuntu virtual machines using Multipass.

Prerequisites

• Apple M1 or M2 system
• 8GB RAM (16GB preferred).
  • All configurations - One control plane node will be provisioned - kubemaster
  • If you have less than 16GB then only one worker node will be provisioned - kubeworker1
  • If you have 16GB or more then two workers will be provisioned - kubeworker01 and kubeworker2

You'll need to install the following first.

• Multipass - https://multipass.run/install. Follow the instructions to install it and check it is working properly. You should be able to successfully create a test Ubuntu VM following their instructions. Delete the test VM when you're done.
• JQ - https://github.com/stedolan/jq/wiki/Installation#macos

Additionally

• Your account on your Mac must have admin privilege and be able to use sudo

• Clone this repo down to your Mac. Open your Mac's terminal application. All commands in this guide are executed from the terminal.

  mkdir ~/kodekloud
  cd ~/kodekloud
  git clone https://github.com/kodekloudhub/certified-kubernetes-administrator-course.git
  cd certified-kubernetes-administrator-course/apple-silicon

Install Cluster

These instructions follow the steps in the lecture videos fairly closely, however we need to use versions of the various software to install that are compatible with ARM architecture. This means that whereever the lecture shows sofware downloads with linux-amd64 in the name, we are going to choose the corresponding linux-arm64 version.

Step 1 - Provision VMs with Multipass

Because we cannot use VirtualBox and are instead using Multipass, a script is provided to create the three VMs.

1. Run the VM deploy script from your Mac terminal

   ./deploy-virtual-machines.sh

2. Verify you can connect to all three (two if your Mac only has 8GB RAM) VMs:

   multipass shell kubemaster

   You should see a command prompt like ubuntu@kubemaster:~$

   Type the following to return to the Mac terminal

   exit

   Do this for kubeworker01 and kubeworker02 as well

   In the following instructions when it says "connect to" any of the VMs, it means use the multipass shell command as above.

Step 2 - Set up Operating System Prerequisites

Connect to each VM in turn, and run the following:

1. Execute the following commands in each VM terminal

   # Load required kernel modules
   sudo modprobe overlay
   sudo modprobe br_netfilter
   
   # Persist modules between restarts
   cat <<EOF | sudo tee /etc/modules-load.d/k8s.conf
   overlay
   br_netfilter
   EOF
   
   # Set required networking parameters
   cat <<EOF | sudo 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
   
   # Apply sysctl params without reboot
   sudo sysctl --system

Step 3 - Set up Container Runtime (containerd)

Here we deviate slightly from the lecture. Using the default version of containerd that is provided by apt-get install results in a cluster with crashlooping pods, so we install a version that works by downloading directly from their github site.

Connect to each VM in turn, and run the following scripts:

1. Download and unzip the containerd application

   curl -LO https://github.com/containerd/containerd/releases/download/v1.7.0/containerd-1.7.0-linux-arm64.tar.gz
   sudo tar Czxvf /usr/local containerd-1.7.0-linux-arm64.tar.gz

2. Download and place the systemd unit file

   curl -LO https://raw.githubusercontent.com/containerd/containerd/main/containerd.service
   sudo mkdir -p /usr/lib/systemd/system
   sudo mv containerd.service /usr/lib/systemd/system/

3. Create containerd configuration file

   sudo mkdir -p /etc/containerd/
   sudo containerd config default | sudo tee /etc/containerd/config.toml > /dev/null

4. Enable systemd CGroup driver

   sudo sed -i 's/SystemdCgroup \= false/SystemdCgroup \= true/g' /etc/containerd/config.toml

5. Set containerd to auto-start at boot (enable it).

   sudo systemctl daemon-reload
   sudo systemctl enable --now containerd

Step 4 - Install kubeadm, kubelet and kubectl

Connect to each VM in turn and perform the following steps

1. Update the apt package index and install packages needed to use the Kubernetes apt repository

   sudo apt-get update
   sudo apt-get install -y apt-transport-https ca-certificates curl

2. Download the Google Cloud public signing key

   curl -fsSL https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-archive-keyring.gpg

3. Add the Kubernetes apt repository

   echo "deb [signed-by=/etc/apt/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list

4. Update apt package index, install kubelet, kubeadm and kubectl, and pin their version:

   KUBE_VERSION=1.26.4
   sudo apt-get update
   sudo apt-get install -y kubelet=${KUBE_VERSION}-00 jq kubectl=${KUBE_VERSION}-00 kubeadm=${KUBE_VERSION}-00 runc kubernetes-cni=1.2.0-00
   sudo apt-mark hold kubelet kubeadm kubectl

5. Configure crictl to work with containerd

   sudo crictl config runtime-endpoint unix:///var/run/containerd/containerd.sock

Step 5 - Provisioning the Kubernetes Cluster

1. Configure the Control Plane

   1. Connect to the control plane node

   2. Determine the IP address of the control plane node. We will need it for the forthcoming kubeadm init command.

      dig +short kubemaster | grep -v 127

   3. Initialize control plane.

      As per the lecture, we are going to use a pod CIDR of 10.244.0.0/16. Run the following command, replacing [IP] with the IP address you got from the previous step

      sudo kubeadm init --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=[ip]

   4. Set up the kubeconfig file.

      mkdir ~/.kube
      sudo cp /etc/kubernetes/admin.conf ~/.kube/config
      sudo chown ubuntu:ubuntu ~/.kube/config
      chmod 600 ~/.kube/config

   5. Verify the cluster is contactable

      kubectl get pods -n kube-system

      You should see some output. Pods may not all be ready yet.

   6. Install Weave for cluster networking

      kubectl apply -f "https://github.com/weaveworks/weave/releases/download/v2.8.1/weave-daemonset-k8s-1.11.yaml"

      It will take up to a minute for the weave pod to be ready

   7. Prepare the join command for the worker nodes

      kubeadm token create --print-join-command

      Copy the output of this. We will need to paste it on the worker(s)

2. Configure the worker nodes

   For each worker node

   1. Connect to the worker node

   2. Paste the join command you copied from the final step of configuring the control plane to the command prompt and run it. Put sudo on the command line first, then passte the join command after sudo so it looks like

      sudo kubeadm join 192.168.64.4:6443 --token whd8v4.EXAMPLE --discovery-token-ca-cert-hash sha256:9537c57af216775e26ffa7ad3e495-5EXAMPLE`
      

Notes

1. Deleting the VMs

   ./delete-virtual-machines.sh
   

2. Stopping and restarting the VMs

   To stop the VMs, stop the workers first, then finally kubemaster

   multipass stop kubeworker01
   multipass stop kubeworker02
   multipass stop kubemaster

   To restart them, start the control plane first

   multipass start kubemaster
   # Wait 30 sec or so
   multipass start kubeworker01
   multipass start kubeworker02

3. To see the state of VMs, run

   multipass list

4. Multipass allocates IP addresses from the Mac's DHCP server to assign to VMs. When the VMs are deleted, it does not release them. If you build and tear down this a few times, you will run out of addresses on the network used for this purpose. Reclaiming them is a manaul operation. To do this, you must remove the spent addresses from the file /var/db/dhcpd_leases This file looks like this:

   {
           name=kubemaster
           ip_address=192.168.64.22
           hw_address=1,52:54:0:eb:c4:7
           identifier=1,52:54:0:eb:c4:7
           lease=0x643f6f22
   }
   {
           name=kubeworker01
           ip_address=192.168.64.23
           hw_address=1,52:54:0:93:3d:91
           identifier=1,52:54:0:93:3d:91
           lease=0x643f6f20
   }

   Once you have deleted all your VMs, edit this file and remove all the blocks (including their surrounding { }) related to kubemaster and kubeworker. In the above example you would delete everything you can see. Do this for all kubemsters and kubeworkers.

   sudo vi /var/db/dhcpd_leases