Build a Kubernetes cluster using k3s via Ansible and Terraform

Author: https://github.com/itwars and https://github.com/NatiSayada

K3s Ansible Playbook

Build a Kubernetes cluster using Ansible with k3s. The goal is easily install a Kubernetes cluster on machines running:

• Debian
• Ubuntu
• CentOS

on processor architecture:

• x64
• arm64
• armhf

System requirements

Deployment environment must have Ansible 2.4.0+ Master and nodes must have passwordless SSH access Terraform installed Proxmox server

Usage

proxmox setup

This setup is relayig on cloud-init image and its save a lot of the image configuration. I use ubuntu focal image, to configure the cloud-init image you will need to connect to a linux server and run the following:

install image tools on the server (you will need another server, this tools cannot be installed on proxmox)

apt-get install libguestfs-tools

Get the image that you would like to work with. you can browse to https://cloud-images.ubuntu.com and select any other version that you wold like to work with. it can also work for debian and centos (R.I.P)

wget https://cloud-images.ubuntu.com/focal/current/focal-server-cloudimg-amd64.img

update the image and install proxmox agent - this is a must if we want terrafom to work properly. it can take a minute to add the packege to the image.

virt-customize --install qemu-guest-agent

now we need will create a new vm

qm create 9000 --name "ubuntu-focal-cloudinit-template" --memory 2048 --net0 virtio,bridge=vmbr0

for ubuntu images, rename the image suffix

mv focal-server-cloudimg-amd64.img focal-server-cloudimg-amd64.qcow2

import the disk

qm importdisk 9000 focal-server-cloudimg-amd64.qcow2 local-lvm

configure the vm to use the image

qm set 9000 --scsihw virtio-scsi-pci --scsi0 local-lvm:vm-9000-disk-0

terraform setup

Rename the file terraform/vars.sample to terraform/vars.tf and update all the vars.

to run the terrafom, you will need to cd into terraform and run:

terraform init
terraform plan
terraform apply

it can take some time to create the servers on proxmox but you can monitor them over proxmox.

ansible setup

First create a new directory based on the sample directory within the inventory directory:

cp -R inventory/sample inventory/my-cluster

Second, edit inventory/my-cluster/hosts.ini to match the system information gathered above. For example:

[master]
192.16.35.12

[node]
192.16.35.[10:11]

[k3s_cluster:children]
master
node

If needed, you can also edit inventory/my-cluster/group_vars/all.yml to match your environment.

Start provisioning of the cluster using the following command:

ansible-playbook site.yml -i inventory/my-cluster/hosts.ini

Kubeconfig

To get access to your Kubernetes cluster just

scp debian@master_ip:~/.kube/config ~/.kube/config