Deploy Kubernetes cluster on DigitalOcean with terraform

Installing Terraform

To install terraform, follow installation instructions here.

Digital Ocean provider

        
      
terraform {
  required_providers {
    digitalocean: {
      source : "digitalocean/digitalocean"
      version: "2.22.3"
    }
  }
}

Authetication

Authetication can be done either with environment variables or terraform variables.

Windows Powershell

Open Powershell and run the following to add new environment variable.

$ENV:DIGITALOCEAN_ACCESS_TOKEN: 'token'

To set the token as environment variable Persistently

        
      
[System.Environment]::SetEnvironmentVariable('DIGITALOCEAN_ACCESS_TOKEN','token')

Bash

        
      
export DIGITALOCEAN_ACCESS_TOKEN='token'

To set the token as environment variable Persistently

echo 'export DIGITALOCEAN_ACCESS_TOKEN='token'' >> ~/.profile

Replace token with the actual token.

Using Terraform variables Create var.tf and add following

        
      
variable "do_token" {
    type: string
    description: "Digital Ocean API Token"
    sensitive: true
}

And add following to provider.tf

        
      
provider "digitalocean" {
  token: var.do_token
}

Variables

Variables and their default values

variable	Remarks	Default
do_cluster_name	Cluster Name	k8s-test
do_region	Region	sfo3
do_pool_name	Cluster Pool Name	k8s-test-pool
do_node_size	Node CPu and Memory	s-1vcpu-2gb
do_nodepool_count	No’s nodes	1
do_pool_ad_name	Additional Pool Name	k8s-test-pool-ad
do_node_ad_size	Node CPu and Memory	s-1vcpu-2gb
do_nodepool_ad_count	Node CPu and Memory	1
do_nodepool_scale	Enable Autoscaling	true
do_node_max	Max no’s nodes for autoscale	3

Cluster

Cluster module can be found in k8s.tf

k8s version

Get latest k8s version supported by Digital Ocean with digitalocean_kubernetes_versions data source.

        
      
data "digitalocean_kubernetes_versions" "get_version" {}

To use version prefix, add version_prefix: "1.24"

        
      
data "digitalocean_kubernetes_versions" "get_version" {
    version_prefix: "1.24."
}

Cluster with pool

deploy cluster with version from version above

        
      
resource "digitalocean_kubernetes_cluster" "k8s_cluster" {
  name   : var.do_cluster_name
  region : var.do_region
  version: data.digitalocean_kubernetes_versions.get_version.latest_version

  node_pool {
    name      : var.do_pool_name
    size      : var.do_node_size
    auto_scale: var.do_nodepool_scale
    min_nodes : var.do_nodepool_count
    max_nodes : var.do_node_max
  }
}

Aditional pool

        
      
resource "digitalocean_kubernetes_node_pool" "k8s_cluster_pool_ad" {
  cluster_id: digitalocean_kubernetes_cluster.k8s_cluster.id

  name      : var.do_pool_ad_name
  size      : var.do_node_ad_size
  auto_scale: var.do_nodepool_scale
  min_nodes : var.do_nodepool_ad_count
  max_nodes : var.do_node_max
}

Deploying

Before deploying make sure everything is as per spec by validating with

terraform validate

Plan the depliyment with

terraform plan

Deploy the cluster with

terraform deploy

Append -var "do_token=token" to use different token.

Destroy

To destroy the infrastructure, run

terraform destroy