ThePixelDeveloper / terraform

Infrastructure for a fault tolerant Nomad cluster.

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Features

• Infrastructure for a fault tolerant Nomad (alternative job scheduler to Kubernetes) cluster.

What?

This repository contains the code to spin up Consul and Nomad servers and clients, ready to be provisioned by Ansible. Without this project I'd have to manually create these machines on Hetzner Cloud, a time consuming process.

We default to having three servers in the cluster, meaning the platform can survive with a server going down.

Setup

Firstly, register for Terraform Cloud and Hetzner Cloud.

1. Rename backend.hcl.example to backend.hcl and fill in with your Terraform Cloud values.
2. Rename terraform.tfvars.example to terraform.tfvars and fill in with your Hetzner Cloud values.
3. Run terraform init -backend-config=backend.hcl
4. Run terraform plan to see what's going to happen.
5. Run terraform apply to apply changes.

Variables

General

Name	Default	Description
hetzner_cloud_token		The Hetzner Cloud API Token
private_network_range	10.0.0.0/8	Private network range
private_network_name	consul-nomad	The name of the private network

Consul Server

Name	Default	Description
consul_server_name_format	consul-server-%s	The name format of the consul servers
consul_server_count	3	The number of consul servers to provision
consul_server_type	cx11	The type of machine to use for the consul servers
consul_server_image	ubuntu-18.04	The image to use for the consul servers
consul_server_location	nbg1	The Hetzner datacenter location
consul_server_ssh_keys	[]	The IDs of the ssh keys to be used for the consul servers.

Nomad Server

Name	Default	Description
nomad_server_name_format	nomad-server-%s	The name format of the nomad servers
nomad_server_count	3	The number of nomad servers to provision
nomad_server_type	cpx11	The type of machine to use for the nomad servers
nomad_server_image	ubuntu-18.04	The image to use for the nomad servers
nomad_server_location	nbg1	The Hetzner datacenter location
nomad_server_ssh_keys	[]	The IDs of the ssh keys to be used for the nomad servers.

Nomad Client

Name	Default	Description
nomad_client_name_format	nomad-client-%s	The name format of the nomad clients
nomad_client_count	3	The number of nomad clients to provision
nomad_client_type	cpx31	The type of machine to use for the nomad clients
nomad_client_image	ubuntu-18.04	The image to use for the nomad clients
nomad_client_location	nbg1	The Hetzner datacenter location
nomad_client_ssh_keys	[]	The IDs of the ssh keys to be used for the nomad clients.

Output

We output an Ansible inventory file to ./build/ansible/inventory/hetzner.

[consul_server]
... ipv4_address_private=10.0.0.2
... ipv4_address_private=10.0.0.3
... ipv4_address_private=10.0.0.4

[nomad_server]
... ipv4_address_private=10.0.1.2
... ipv4_address_private=10.0.1.3
... ipv4_address_private=10.0.1.4

[consul_client]
... ipv4_address_private=10.0.1.2
... ipv4_address_private=10.0.1.3
... ipv4_address_private=10.0.1.4
... ipv4_address_private=10.0.2.2
... ipv4_address_private=10.0.2.3
... ipv4_address_private=10.0.2.4

[nomad_client]
... ipv4_address_private=10.0.2.2 ipv4_address_floating=...
... ipv4_address_private=10.0.2.3 
... ipv4_address_private=10.0.2.4