rke cluster

rancher/rke/README.md

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+# Set up a Highly Available Kubernetes Cluster using Rancher RKE
+Follow this documentation to set up a highly available Kubernetes cluster on __Ubuntu 20.04 LTS__ machines using Rancher's RKE.
+
+This documentation guides you in setting up a cluster with three nodes all of which play master, etcd and worker role.
+
+## Vagrant Environment
+|Role|FQDN|IP|OS|RAM|CPU|
+|----|----|----|----|----|----|
+|Master, etcd, worker|node1.example.com|172.16.16.101|Ubuntu 20.04|2G|2|
+|Master, etcd, worker|node2.example.com|172.16.16.102|Ubuntu 20.04|2G|2|
+|Master, etcd, worker|node3.example.com|172.16.16.103|Ubuntu 20.04|2G|2|
+
+> * Password for the **root** account on all these virtual machines is **kubeadmin**
+> * Perform all the commands as root user unless otherwise specified
+
+## Pre-requisites
+If you want to try this in a virtualized environment on your workstation
+* Virtualbox installed
+* Vagrant installed
+* Host machine has atleast 8 cores
+* Host machine has atleast 8G memory
+
+## Bring up all the virtual machines
+```
+vagrant up
+```
+
+## Download RKE Binary
+##### Download the latest release from the Github releases page
+[Rancher RKE Releases - Github](https://github.com/rancher/rke/releases)
+
+## Set up password less SSH Logins on all nodes
+We will be using SSH Keys to login to root account on all the kubernetes nodes. I am not going to set a passphrase for this ssh keypair.
+##### Create an ssh keypair on the host machine
+```
+ssh-keygen -t rsa -b 2048
+```
+##### Copy SSH Keys to all the kubernetes nodes
+The root password is **kubeadmin**
+```
+ssh-copy-id [email protected]
+ssh-copy-id [email protected]
+ssh-copy-id [email protected]
+```
+
+## Prepare the kubernetes nodes (node1, node2, node3)
+##### Disable Firewall
+```
+ufw disable
+```
+##### Disable swap
+```
+swapoff -a; sed -i '/swap/d' /etc/fstab
+```
+##### Update sysctl settings for Kubernetes networking
+```
+cat >>/etc/sysctl.d/kubernetes.conf<<EOF
+net.bridge.bridge-nf-call-ip6tables = 1
+net.bridge.bridge-nf-call-iptables = 1
+EOF
+sysctl --system
+```
+##### Install docker engine
+```
+{
+  apt install -y apt-transport-https ca-certificates curl gnupg-agent software-properties-common
+  curl -fsSL https://download.docker.com/linux/ubuntu/gpg | apt-key add -
+  add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
+  apt update && apt install -y docker-ce=5:19.03.10~3-0~ubuntu-focal containerd.io
+}
+```
+
+## Bring up Kubernetes cluster
+##### Create cluster configuration
+```
+rke config
+```
+Once gone through this interactive cluster configuration, you will end up with cluster.yml file in the current directory.
+
+##### Provision the cluster
+```
+rke up
+```
+Once this command completed provisioning the cluster, you will have cluster state file (cluster.rkestate) and kube config file (kube_config_cluster.yml) in the current directory.
+
+## Downloading kube config to your local machine
+On your host machine
+```
+mkdir ~/.kube
+cp kube_config_cluster.yml ~/.kube/config
+```
+
+## Verifying the cluster
+```
+kubectl cluster-info
+kubectl get nodes
+kubectl get cs
+```
+
+Have Fun!!

rancher/rke/Vagrantfile

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+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+ENV['VAGRANT_NO_PARALLEL'] = 'yes'
+
+Vagrant.configure(2) do |config|
+
+  config.vm.provision "shell", path: "bootstrap.sh"
+
+  NodeCount = 3
+
+  # Kubernetes Nodes
+  (1..NodeCount).each do |i|
+    config.vm.define "node#{i}" do |node|
+      node.vm.box = "bento/ubuntu-20.04"
+      node.vm.hostname = "node#{i}.example.com"
+      node.vm.network "private_network", ip: "172.16.16.10#{i}"
+      node.vm.provider "virtualbox" do |v|
+        v.name = "node#{i}"
+        v.memory = 2048
+        v.cpus = 2
+      end
+    end
+  end
+
+end

rancher/rke/bootstrap.sh

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+#!/bin/bash
+
+# Enable ssh password authentication
+echo "[TASK 1] Enable ssh password authentication"
+sed -i 's/^PasswordAuthentication .*/PasswordAuthentication yes/' /etc/ssh/sshd_config
+echo 'PermitRootLogin yes' >> /etc/ssh/sshd_config
+systemctl reload sshd
+
+# Set Root password
+echo "[TASK 2] Set root password"
+echo -e "kubeadmin\nkubeadmin" | passwd root >/dev/null 2>&1