Proxmox Virtual Environment is an awesome virtualization solution. Kubernetes is an awesome containerization solution. So why not combine those great technologies? In this video, you’ll see the entire process of setting up your very own Kubernetes cluster from scratch, with Proxmox shown as the platform. But even if you don’t plan on using Proxmox, this method will work just fine on other solutions as well, including physical servers. By the end of this video, you’ll have your own cluster ready to go!
Also, be sure to check out the brand-new book, Mastering Ubuntu Server 4th Edition! It’s available now, and covers Ubuntu Server 22.04 LTS.
To follow along with this tutorial, you’ll need:
- At least two Ubuntu Server 22.04 instances (one for the controller, one for at least one node)
- A static IP address or DHCP reservation on those instances, so their IP addresses cannot change
- The controller node should have at least 2GB of RAM and 2 cores
- The node instances can have a single gigabyte of RAM and a single CPU core (or more if you prefer)
Note: This tutorial utilizes Ubuntu Server 22.04. If you choose to use a different distribution or a different version of Ubuntu, these commands may not work.
Setting up the cluster
The following commands are to be run on the controller node (unless otherwise stated).
Setting up a static IP
Note, a static lease is preferred, but you can use the following Netplan config example to serve as a basis of yours if you need to set up a static IP.
network: version: 2 ethernets: eth0: addresses: [10.10.10.213/24] nameservers: addresses: [10.10.10.1] routes: - to: default via: 10.10.10.1
This Kubernetes cluster will utilize the
containerd runtime. To set that up, we’ll first need to install the required package:
sudo apt install containerd
Create the initial configuration:
sudo mkdir /etc/containerd
containerd config default | sudo tee /etc/containerd/config.toml
For this cluster to work properly, we’ll need to enable
SystemdCgroup within the configuration. To do that, we’ll need to edit the config we’ve just created:
sudo nano /etc/containerd/config.toml
Within that file, find the following line of text:
Underneath that, find the
SystemdCgroup option and change it to
true, which should look like this:
SystemdCgroup = true
Kubernetes requires swap to be disabled. To turn off swap, we can run the following command:
sudo swapoff -a
Next, edit the
/etc/fstab file and comment out the line that corresponds to swap (if present). This will help ensure swap doesn’t end up getting turned back on after reboot.
To enable bridging, we only need to edit one config file:
sudo nano /etc/sysctl.conf
Within that file, look for the following line:
Uncomment that line by removing the
# symbol in front of it, which should make it look like this:
The next step is to enable
br_netfilter by editing yet another config file:
sudo nano /etc/modules-load.d/k8s.conf
Add the following to that file (the file should actually be empty at first):
Reboot your servers
Reboot each of your instances to ensure all of our changes so far are in place:
The next step is to install the packages that are required for Kubernetes. First, we’ll add the required GPG key:
sudo curl -fsSLo /usr/share/keyrings/kubernetes-archive-keyring.gpg https:// packages.cloud.google.com/apt/doc/apt-key.gpg
After that, install the packages that are required for Kubernetes:
sudo apt install kubeadm kubectl kubelet
Controller node only: Initialize our Kubernetes cluster
So long as you have everything complete so far, you can initialize the Kubernetes cluster now. Be sure to customize the first IP address shown here (not the second) and also change the name to match the name of your controller.
sudo kubeadm init --control-plane-endpoint=172.16.250.216 --node-name controller --pod-network-cidr=10.244.0.0/16
After the initialization finishes, you should see at least four commands printed within the output.
Setting up our user account to manage the cluster
Three commands will be shown in the output from the previous command, and these commands will give our user account access to manage our cluster. Here are those related commands to save you from having to search the output for them:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
suod chown $(id -u):$(id -g) $HOME/.kube/config
Those commands should allow you to manage the cluster, without needing to use the
root account to do so.
Install an Overlay Network
The following command will install the Flannel overlay network (an overlay network is required for this to function).
kubectl apply -f https://raw.githubusercontent.com/flannel-io/flannel/master/ Documentation/kube-flannel.yml
The join command, which you will receive from the output once you initialize the cluster, can be ran on your node instances now to get them joined to the cluster. The following command will help you monitor which nodes have been added to the controller (it can take several minutes for them to appear):
kubectl get nodes
If for some reason the join command has expired, the following command will provide you with a new one:
kubeadm token create --print-join-command
Deploying a container within our cluster
Create the file
pod.yml with the following contents:
apiVersion: v1 kind: Pod metadata: Chapter 18 25 name: nginx-example labels: app: nginx spec: containers: - name: nginx image: linuxserver/nginx ports: - containerPort: 80 name: "nginx-http"
Apply the file with the following command:
kubectl apply -f pod.yml
You can check the status of this deployment with the following command:
kubectl get pods
Creating a NodePort Service
Setting up a NodePort service is one of the methods we can use to be able to access the container from outside the pod network. To set this up, first create the following file as
apiVersion: v1 kind: Service metadata: name: nginx-example spec: type: NodePort ports: - name: http port: 80 nodePort: 30080 targetPort: nginx-http selector: app: nginx
You can apply that file with the following command:
kubectl apply -f service-nodeport.yml
To check the status of the service deployment, you can use the following command:
kubectl get service
And now, you have your very own Kubernetes cluster, congratulations!