Build a multi node kubernetes cluster using k3s (I'm in Kali Linux)

   
 kubernetes  Kali Linux  
 sysadmin  
Table of Content

Preface

Main idea: This is tutorial how to setup kubernetes cluster multi node (using k3s)

List of Cluster

This is tool for running a kubernetes cluster with one node or multi node in my virtual machine - Minikube (single node) - Docker in Docker - Microk8s (single node) - k3s (multi node) - build from stratch

Reading

Information about option to run kubernetes locally - https://developer.ibm.com/technologies/containers/blogs/options-to-run..

k3s master and worker setup

Prerequisites

Setup k3s server (master) in Ubuntu 18.04

Using k3s is simple way that you can join host (In this case Kali Linux machine) to the Master node (Ubuntu)

source: https://www.liquidweb.com/kb/how-to-install-and-configure-k3s-on-ubuntu-18-04/

In this node I have IP: 192.168.0.15

curl -sfL https://get.k3s.io | sh -
systemctl status k3s

The kubeconfig file is written to `/etc/rancher/k3s/k3s.yaml. This file is required for the Kubernetes configuration. Let see configuration file

$ sudo cat /etc/rancher/k3s/k3s.yaml

apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: LS0tLS1CR...lRJRklDQVRFLS0tLS0K
    server: https://127.0.0.1:6443
  name: default
contexts:
- context:
    cluster: default
    user: default
  name: default
current-context: default
kind: Config
preferences: {}
users:
- name: default
  user:
    client-certificate-data: LS0tLS1CRUdJT...VJUSUZJFURS0tLS0tCg==

    client-key-data: 3I0UndHb3FMT2NGgUFJ...SBLRVktLS0tLQo=

Add authentication at users: menu

- name: default
  user:
    username: bima
    password: bismillah

Be sure, k3s services is run and check node list with command sudo k3s kubectl get node

And it say status: ready.

To install K3s on the server, the agent needs to passing K3S_URL along with the K3S_TOKEN or K3S_CLUSTER_SECRET variables.

We will use the K3S_TOKEN variable, we can see it in /var/lib/rancher/k3s/server/node-token

$ sudo cat /var/lib/rancher/k3s/server/node-token
K1098526a9f3f28921a0248386d6c207bde4c260edec841da201b757d25f7d1c931::server:666367da95e338a438510908665a6f2d

this token will be add in worker host with NODE_TOKEN="<token_here>". In my case I use Kali Linux as worker node.

Setup k3s worker host in Kali Linux

installation

curl -sfL https://get.k3s.io | sh -

set temporary $PATH first

NODE_TOKEN="K1098526a9f3f28921a0248386d6c207bde4c260edec841da201b757d25f7d1c931::server:666367da95e338a438510908665a6f2d"

and then, add k3s master’s token

sudo k3s agent --server https://192.168.0.15:6443 --token ${NODE_TOKEN}

But, in Kali Linux does not supported from k3s haha. In installation will be fail.

Like This

To examine this problem. For the further I will setup with another cluster. Maybe it’s single nodes.