Kubernetes Cluster Installation - Ubuntu 22.04

A step-by-step guide to install Kubernetes cluster on Ubuntu 22.04 using Kubeadm command .

Master Node: 192.168.1.100 master01.tracston.com
Worker Node: 192.168.1.101 – worker01.tracston.com
Worker Node: 192.168.1.102 – worker02.tracston.com

Note: Change the hostname to your domain
Note: Taking into consideration multi master setup

Set hostname and add entries in the hosts file
Login to to master node and set hostname using hostnamectl command,

sudo hostnamectl set-hostname “master01.tracston.com”

On the worker nodes

sudo hostnamectl set-hostname “worker01.tracston.com”
sudo hostnamectl set-hostname “worker02.tracston.com”

Add the following entries in /etc/hosts file on each node

192.168.1.100 master01.tracston.com
192.168.1.101 worker01.tracston.com
192.168.1.102 worker02.tracston.com

Disable swap & add kernel settings

sudo swapoff -a
sudo sed -i ‘/ swap / s/^\(.*\)$/#\1/g’ /etc/fstab

Load the following kernel modules on all the nodes,

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

sudo modprobe overlay
sudo modprobe br_netfilter

Set the following Kernel parameters for Kubernetes, run beneath tee command

sudo 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

#Reload new settings

sudo sysctl –system

Install Docker

sudo apt install -y curl gnupg2 software-properties-common apt-transport-https ca-certificates

Enable docker repository

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

Configure containerd to start using systemd as cgroup.

containerd config default | sudo tee /etc/containerd/config.toml >/dev/null 2>&1
sudo sed -i ‘s/SystemdCgroup \= false/SystemdCgroup \= true/g’ /etc/containerd/config.toml

Restart and enable containerd service

sudo systemctl restart containerd
sudo systemctl enable containerd

Install kubernetes

curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add –
sudo apt-add-repository “deb http://apt.kubernetes.io/ kubernetes-xenial main”
sudo apt update
sudo apt install -y kubelet kubeadm kubectl
sudo apt-mark hold kubelet kubeadm kubectl

Initialize Kubernetes cluster with Kubeadm command

Kubeadm init –pod-network-cidr=10.0.0.0/16

To work with the newly created cluster copy the configuration file to your home dir

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

Check Cluster Status

kubectl cluster-info

Follow the same for installation on the nodes

When finished installing the master node there was an output command how to join new worker nodes to the cluster

Run the following command to join the node to the cluster

sudo kubeadm join k8smaster.example.net:6443 –token xxxxxxxxxxxxxxxxxxxxxx \
–discovery-token-ca-cert-hash sha256:0494aa7fc6ced8tj984yuetjhglkefdhjw98utw616656932ff9173c94962a36

Check the nodes status from master node

kubectl get nodes

Install Networking Calico

kubectl create -f https://raw.githubusercontent.com/projectcalico/calico/v3.25.0/manifests/tigera-operator.yaml

#Download the custom resources if you wish to customize Calico

curl https://raw.githubusercontent.com/projectcalico/calico/v3.25.0/manifests/custom-resources.yaml -O
kubectl create -f custom-resources.yaml

Check the nodes status. should be status Ready

kubectl get nodes

Attachment: commands.txt

To reset the configuration of an existing kubernetes type

kubeadm reset