Kubernetes_Cluster_Master_Setup.txt

# source: https://computingforgeeks.com/deploy-kubernetes-cluster-on-ubuntu-with-kubeadm/
# kubeadm - a CLI tool that will install and configure the various components of a cluster in a standard way.
# kubelet - a system service/program that runs on all nodes and handles node-level operations.
# kubectl - a CLI tool used for issuing commands to the cluster through its API Server.

# remove older docker version
sudo apt-get purge -y docker* containerd* runc && sudo apt autoremove -y

# setup your OS
sudo apt-get update && sudo apt-get install -y apt-transport-https gnupg2 curl gnupg-agent software-properties-common

# add google repository for docker
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"

# add google repository for kubernetes
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee -a /etc/apt/sources.list.d/kubernetes.list

# disable firewall
systemctl stop ufw.service
systemctl disable ufw.service

# Disable local swap
sudo swapoff -a
sudo sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab

# install kubernetes
sudo apt-get update && sudo apt install -y kubeadm kubectl kubelet

# Configure sysctl.
sudo modprobe overlay
sudo modprobe br_netfilter

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

sudo sysctl --system

# install the 19.03 version for kubernetes 1.20.2 # check the repository versions 'apt-cache madison docker-ce'
sudo apt-get update && sudo apt-get install -y docker-ce=5:19.03.14~3-0~ubuntu-focal docker-ce-cli=5:19.03.14~3-0~ubuntu-focal containerd.io

# change cgdriver to systemd (fix install error in kubeadm)
# Create required directories
sudo mkdir -p /etc/systemd/system/docker.service.d

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

# Start and enable Services
sudo systemctl daemon-reload
sudo systemctl restart docker
sudo systemctl enable docker

# check docker installed version
docker --version

# check if the dicker service is enabled
systemctl status docker.service
# enable the docker service if its not enable
# systemctl enable docker.service
# reload and restart systemctl
# sudo systemctl daemon-reload
# sudo systemctl restart docker

# start kubernetes host cluster
kubeadm init

# add node to kubernetes cluster host from the host setup
# kubeadm join 192.168.50.71:6443 --token xxx --discovery-token-ca-cert-hash sha256:xxx

# start using your cluster, you need to run the following as a 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

# Install the Calico network plugin
curl https://docs.projectcalico.org/manifests/calico.yaml -O
kubectl apply -f calico.yaml

# check nodes on host
kubectl get nodes

# check pods on host
kubectl get pods --all-namespaces

# keep packages from updating
sudo apt-mark hold docker-ce docker-ce-cli kubelet kubeadm kubectl

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# NotReady error in kubernetes
kubectl apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"

# wait for 1-2 min and test the cluster
kubectl describe nodes

# check nodes on host
kubectl get nodes

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# kubeadm reset pr clear up settings
kubeadm reset