Building a basic kubernetes cluster

kubernetes_cluster _init.sh

#!/bin/bash

#coomands were run on a ubuntu os


#Docker and Kubernetes repositories:

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"
   
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -

cat << EOF | sudo tee /etc/apt/sources.list.d/kubernetes.list
deb https://apt.kubernetes.io/ kubernetes-xenial main
EOF

#Install Docker and Kubernetes packages:


sudo apt-get update

sudo apt-get install -y docker-ce=18.06.1~ce~3-0~ubuntu kubelet=1.14.5-00 kubeadm=1.14.5-00 kubectl=1.14.5-00

sudo apt-mark hold docker-ce kubelet kubeadm kubectl

#Enable iptables bridge call:


echo "net.bridge.bridge-nf-call-iptables=1" | sudo tee -a /etc/sysctl.conf

sudo modprobe br_netfilter

sudo sysctl -p

#On the Kube master server

sudo nano /proc/sys/net/ipv4/ip_forward
(Changes from 0 to 1) 

sudo kubeadm init --pod-network-cidr=10.244.0.0/16


#Then setup loca kubeconfig in the master server
mkdir -p $HOME/.kube

sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

sudo chown $(id -u):$(id -g) $HOME/.kube/config

#install flannel networking

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/bc79dd1505b0c8681ece4de4c0d86c5cd2643275/Documentation/kube-flannel.yml


#On each kube node server

sudo kubeadm join $controller_private_ip:6443 --token $token --discovery-token-ca-cert-hash $hash