kubernetes

Install Kubernetes on Ubuntu 20.04

See also docker guidelines

On All nodes

1. Install Docker
2. Disable swap
3. Configure the Docker daemon, in particular to use systemd for the management of the container’s cgroups. details

   sudo mkdir /etc/docker
   cat <<EOF | sudo tee /etc/docker/daemon.json
   {
     "exec-opts": ["native.cgroupdriver=systemd"],
     "log-driver": "json-file",
     "log-opts": {
        "max-size": "100m"
     },
     "storage-driver": "overlay2"
   }
   EOF
   

4. Restart docker

   sudo systemctl restart docker
   

5. Install kubeadm

   sudo apt-get update
   sudo apt-get install -y apt-transport-https ca-certificates curl
   sudo curl -fsSLo /usr/share/keyrings/kubernetes-archive-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg
   echo "deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list
   sudo apt-get update
   sudo apt-get install -y kubelet kubeadm kubectl
   sudo apt-mark hold kubelet kubeadm kubectl
   

On Kubernetes Master

1. Init kubernetes master

   sudo kubeadm init --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=<k8s-master-ip>
   

2. Finish setup as regular user.

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

3. Setup cluster network (flannel).

   kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml; 
   

On all Kubernetes workers

sudo kubeadm join <k8s-master-ip>:6443 --token <token> \
	--discovery-token-ca-cert-hash sha256:<token-hash>

Check cluster health

kubectl get nodes
kubectl get -A