As I am new to Kubernetes, I still haven't figured out how to deploy an application on my local network using one or various physical machines. Usually the tutorials on the internet describe situations using minikube, but it is only for local machine tests, isn't it? Or situations where the deploy is performed on cloud platforms, like google.
I would really appreciate some support in where to begin? In my case will I need to install only Kubernetes on the machines? Is it a trivial task?
From https://kubernetes.io/docs/setup/learning-environment/minikube/
Minikube is a tool that makes it easy to run Kubernetes locally. Minikube runs a single-node Kubernetes cluster inside a Virtual Machine (VM) on your laptop for users looking to try out Kubernetes or develop with it day-to-day
If you want to set up your own cluster including, there's quite a few options including kubeadm or kubespray.
Personally I've used Vagrant and Ansible to set up a local Kubernetes cluster using kubeadm - there's a good tutorial here... and here's my implementation :)
You can use kubeadm
, here is a doc which will help you to install it.
Each server will need to have kubeadm
, kubelet
and kubectl
installed.
On master node
you will do kubeadm init
and once the whole process is finished it will provide you with an output which you can run to add worker nodes
. Of course those servers needs to see each other on your network.
There are also other options to install Kubernetes. For example using kops
or kubespray
.
One way is to install kubernetes is via kubeadm.
I've done this with my own VM. But should also work for your physical machines.
Kubeadm allows you to create cluster using any machine that runs Docker.
This guide will help you to create your first cluster with 1 master and 1 worker nodes. (This is based on Debian)
Execute the following command on all 2 machines:
Installing Docker from official repository
$ sudo apt-get update
$ sudo apt-get -y install apt-transport-https ca-certificates curl gnupg2 software-properties-common
$ curl -fsSL https://download.docker.com/linux/$(. /etc/os-release; echo "$ID")/gpg | sudo apt-key add -
$ sudo apt-key fingerprint 0EBFCD88
$ sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/$(. /etc/os-release; echo "$ID") $(lsb_release -cs) stable"
$ sudo apt-get update
$ sudo apt-get install -y docker-ce docker-ce-cli containerd.io
$ sudo groupadd docker
$ sudo usermod -aG docker $USER
Install kubeadm, kubectl and kubelet from official repository
$ sudo apt-get update && sudo apt-get install -y apt-transport-https curl
$ curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
$ sudo su -c "cat > /etc/apt/sources.list.d/kubernetes.list <<EOF
deb https://apt.kubernetes.io/ kubernetes-xenial main
EOF"
$ sudo apt-get update
$ sudo apt-get install -y kubelet kubeadm kubectl
$ sudo apt-mark hold kubelet kubeadm kubectl
Execute the following command only on your master node
Initialize your cluster
$ sudo kubeadm init
When the init finishes, kubeadm will give you the command to add your workers to your cluster. Save this command for later use.
EXAMPLE:
kubeadm join 10.128.0.17:6443 --token 27evky.hoel95h16poqici6 \
--discovery-token-ca-cert-hash sha256:521f69cb935951bbfee142432108caeaeaf1682d8647208ba2f558624890ab63
After the kubeadm init command completes, run the following commands to start using your new cluster
$ mkdir -p $HOME/.kube
$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
$ sudo chown $(id -u):$(id -g) $HOME/.kube/config
Your master is not ready yet, we need to create a cni network (You can choose different CNIs)
$ kubectl apply -f https://docs.projectcalico.org/v3.8/manifests/calico.yaml
Check if your master node is ready. It needs a while to start all dependencies $ kubectl get nodes
EXAMPLE:
user@kubemaster:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
kubemaster NotReady master 32s v1.16.2
To check more details about your node:
$ kubectl describe node <NODENAME>
When your master node is ready you can proceed and run the kubectl join command (saved previously) on your worker nodes:
$ sudo kubeadm join 10.128.0.17:6443 --token 27evky.hoel95h16poqici6 --discovery-token-ca-cert-hash sha256:521f69cb935951bbfee142432108caeaeaf1682d8647208ba2f558624890ab63
Check if your worker node is ready (command must be executed on master node)
$ kubectl get nodes
If you want to have more workers, just repeat the kubectl join command on the new workers.