Installing Kubernetes using kubeadm without installing docker in Ubuntu

First of all, what is Kubernetes?
Kubernetes (K8s) is an orchestration tool that automates the deployment, scaling, and management of containerized applications. It provides key features like:

• Scaling: Automatically scales applications up or down based on demand.
• Updating: Manages rolling updates and rollbacks to ensure seamless application updates.
• High Availability: Ensures applications run without downtime by distributing containers across multiple nodes.
• Load Balancing: Distributes traffic efficiently to maintain performance.
• Self-Healing: Detects and replaces failed containers automatically.

But to happen this thing initial step is to install it
Below are the steps to achieve it.

#Installing Kubernetes using kubeadm in Ubuntu:
sudo apt-get update
sudo apt-get install -y apt-transport-https ca-certificates curl gpg

#Enable IPv4 packet forwarding
#sysctl params required by setup, params persist across reboots
cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf
net.ipv4.ip_forward = 1
EOF
# Apply sysctl params without reboot
sudo sysctl --system
*#verify it by command as the output should be 1: *
sudo sysctl net.ipv4.ip_forward

#(Althoug it present but if not available) make directory with permission if not present you can check by going to this directory /etc/apt/keyrings
_#sudo mkdir -p -m 755 /etc/apt/keyrings_

#Add the Kubernetes repository

curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.31/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg
# This overwrites any existing configuration in /etc/apt/sources.list.d/kubernetes.list
#Execute the below command after creating kubernetes repo
echo 'deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://pkgs.k8s.io/core:/stable:/v1.31/deb/ /' | sudo tee /etc/apt/sources.list.d/kubernetes.list

#As installing k8s version v1.31 no need to install Docker as in k8s instead installing container runtime environment(cri-o, containerd, Docker Engine) it provides the required docker usage stuff

#Add the CRI-O repository:

curl -fsSL https://pkgs.k8s.io/addons:/cri-o:/stable:/v1.31/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/cri-o-apt-keyring.gpg
#Then run the created repo:
echo "deb [signed-by=/etc/apt/keyrings/cri-o-apt-keyring.gpg] https://pkgs.k8s.io/addons:/cri-o:/stable:/v1.31/deb/ /" | sudo tee /etc/apt/sources.list.d/cri-o.list

#Execute the following command
sudo apt-get update
sudo apt-get install -y cri-o kubelet kubeadm kubectl #Install the packages
sudo systemctl start crio.service #This will start the cri-o service
sudo swapoff -a #as this makes the kubelet not to start
sudo modprobe br_netfilter #Bootstrap a cluster

sudo kubeadm init

#Below command gets provided by running kubeadm init which need to be performed
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

#Create cni network
curl https://raw.githubusercontent.com/projectcalico/calico/v3.28.2/manifests/calico.yaml -O

kubectl apply -f calico.yaml

#last will copy and paste the kubeadm join command into the desired node which will be like given below **
**#example:
sudo sudo kubeadm join 192.168.46.157:6443 --token7xlnp0.9uv4z0qr4wvzhtqn \ --discovery-token-ca-cert-hash sha256:4a1a412d2e682556df0bf10dc380c744a98eb99e8c927fa58eb025d5ff7dc694