Xubuntu 24.04 and Kubernetes cluster

Follow this documentation to set up a highly available Kubernetes cluster using Xubuntu 24.04. You can try this out in VMWare Workstation 17 since it has been free for Personal Use

This documentation guides you in setting up a cluster with a master node and one worker node

Environment

On all kubernetes nodes (kmain1, knode1)

1. Upgrade your Xubuntu servers

Provision the servers to be used in the deployment of Kubernetes on Xubuntu 24.04. The setup process will vary depending on the virtualization or cloud environment you’re using.

Once the servers are ready, update them.

sudo apt update
sudo apt -y full-upgrade
[ -f /var/run/reboot-required ] && sudo reboot -f

2. Install kubelet, kubeadm and kubectl

Once the servers are rebooted, add Kubernetes repository for Xubuntu 24.04 to all the servers.

sudo apt install curl apt-transport-https -y
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
curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.31/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg

Then install required packages.

sudo apt update
sudo apt install wget docker.io curl vim git kubelet kubeadm kubectl -y
sudo apt-mark hold kubelet kubeadm kubectl

3. Disable Swap Space

Disable all swaps from /proc/swaps.

sudo swapoff -a

Now disable Linux swap space permanently in /etc/fstab. Search for a swap line and add # (hashtag) sign in front of the line.

$ sudo vim /etc/fstab
#/swap.img    none    swap    sw    0    0

Enable kernel modules and configure sysctl.

# Enable kernel modules
sudo modprobe overlay
sudo modprobe br_netfilter

# Add some settings to sysctl
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 sysctl
sudo sysctl --system

After that configure containerd.

# Configure containerd and start service
sudo su -
mkdir -p /etc/containerd
containerd config default>/etc/containerd/config.toml

In the config.toml

To use the systemd cgroup driver, open vim/etc/containerd/config.toml, change the SystemdCgroup = true

Also change the sandbox image to

sandbox_image = "registry.k8s.io/pause:3.10"

After that perform containerd restart

# restart containerd
sudo systemctl restart containerd
sudo systemctl enable containerd
systemctl status containerd

On kmain1

We now want to initialize the machine that will run the control plane components which includes etcd (the cluster database) and the API Server.

Pull container images:

$ sudo kubeadm config images pull

Initialize Kubernetes Cluster

$ sudo kubeadm init 
--pod-network-cidr=10.1.0.0/16 
--cri-socket unix://var/run/containerd/containerd.sock 
--upload-certs 
--control-plane-endpoint=dev-k8s-cluster.example.io

Once you see the initialization has completed, there is a long list of tasks to proceed, to which I touch below

Your Kubernetes control-plane has initialized successfully!

To start using your cluster, you need to run the following as a regular user:
#do this
  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

Next download Calico

curl https://raw.githubusercontent.com/projectcalico/calico/v3.28.1/manifests/calico.yaml -O

We need to edit the calico file, since we have specify the ip range to 10.1.0.0/16, so lets make it over to the calico yaml, make the change as below. If you wish to use Calico and your own defined ip range, this should be changed

Next apply the yaml file

kubectl apply -f calico.yaml

You are done for KMain1

On knode1

Next lets look into the Worker node, as usual, you can follow the step until the containerd section and lastly perform this to join the cluster

kubeadm join dev-k8s-cluster.example.com:6443 --token sr4l2l.2kvot0pfalh5o4ik \
    --discovery-token-ca-cert-hash sha256:c692fb047e15883b575bd6710779dc2c5af8073f7cab460abd181fd3ddb29a18