Kubernetes cluster on Digital Ocean

Terraform module which creates a basic Kubernetes cluster on DigitalOcean

Supports:

Kubernetes v1.8.8
Kubernetes v1.9.4

Features:

This module creates a simple Kubernetes cluster on DigitalOcean with the following features:

Single Kubernetes master
Configurable number of Kubernetes worker nodes
Firewall configured to deny external access other than port 22 by default
DigitalOcean private network
DigitalOcean cloud controller which automatically creates a DigitalOcean load balancer creation when a new service is defined
Packer build with base software

Usage:

To create a Kubernetes cluster create the base image with Packer as shown in the example cluster , then add the following module to your Terraform config replacing the values for the inputs as required.

module "k8s_cluster" {
  source = "nicholasjackson/k8s/digitalocean"

  namespace = "my_k8s_cluster"

  ssh_public_key  = "~/.ssh/server_rsa.pub"
  ssh_private_key = "~/.ssh/server_rsa"

  image_name = "k8s-1.9.4-00-ubuntu-16-04-x64"
  size       = "s-1vcpu-1gb"

  k8s_version = "v1.9.4"
  k8s_workers = 2

  digitalocean_api_token = "${var.digitalocean_api_token}"
}

variable "digitalocean_api_token" {
  description = "API token for digital ocean, required by the K8s cloud controller"
}

Inputs

The module defines the following inputs:

name	description
namespace	The namespace for the application
region	DigitalOcean region in which to create the cluster
size	DigitalOcean droplet size, details of available droplets can be found in the docs https://developers.digitalocean.com/documentation/v2/#sizes Kubernetes
ssh_public_key	Path to the SSH public key to add to the nodes
ssh_private_key	Path of the SSH private key used for provisioning
image_name	Digital ocean snapshot used as a base image
k8s_token	Optional token to be used for nodes to join the cluster, if ommited a token will be generated
k8s_version	Kubernetes version, default v1.9.4
k8s_workers	Number of workers to create, default 2
digitalocean_api_token	DigitalOcean API token, required to provision cloud load balancers

Outputs

The module defines the following outputs:

name	description
master_public_ip	Public IP address of the K8s master
master_private_ip	Private IP of the K8s master
workers_public_ip	List of Public IP addresses for the K8s workers
workers_private_ip	List of Private IP addresses for the K8s workers
private_key	Path to the SSH private key used for provisioning the nodes
public_key	Path to the SSH public key provisioned to the nodes
join_token	Join token used when creating the cluster, join tokens have a life span of 24hrs

Example

For more detailed example on useage, including instructions on creating a base image with Packer, and how to access the cluster using kubectl please see the README in the examples folder.

example cluster

Digital Ocean Droplet Sizes

The table below lists the currently available droplets, data obtained from the DigitalOcean API 19/03/2018. NOTE: Kubernetes requires a minimum of 1024mb of ram to run.

Slug	Memory	Vcpus	Disk	Transfer	Price monthly	Price hourly	Regions	Available
512mb	512	1	20	1	5	0.007439999841153622	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-1vcpu-1gb	1024	1	25	1	5	0.007439999841153622	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
1gb	1024	1	30	2	10	0.01487999968230724	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-1vcpu-2gb	2048	1	50	2	10	0.01487999968230724	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-1vcpu-3gb	3072	1	60	3	15	0.02232000045478344	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-2vcpu-2gb	2048	2	60	3	15	0.02232000045478344	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-3vcpu-1gb	1024	3	60	3	15	0.02232000045478344	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
2gb	2048	2	40	3	20	0.02975999936461449	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-2vcpu-4gb	4096	2	80	4	20	0.02975999936461449	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
4gb	4096	2	60	4	40	0.05951999872922897	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
c-2	4096	2	25	4	40	0.05999999865889549	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-4vcpu-8gb	8192	4	160	5	40	0.05951999872922897	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
8gb	8192	4	80	5	80	0.1190500035881996	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
c-4	8192	4	50	5	80	0.1190000027418137	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-6vcpu-16gb	16384	6	320	6	80	0.1190500035881996	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
16gb	16384	8	160	6	160	0.2381000071763992	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
c-8	16384	8	100	6	160	0.2380000054836273	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-8vcpu-32gb	32768	8	640	7	160	0.2381000071763992	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
s-12vcpu-48gb	49152	12	960	8	240	0.3571400046348572	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true
32gb	32768	12	320	7	320	0.4761900007724762	ams2,ams3,blr1,fra1,lon1,nyc1,nyc2,nyc3,sfo1,sfo2,sgp1,tor1	true