Terraform

Basic Commands

Initialise configuration: (use folder as a location to store terraform configuration files )

terraform init

Format configuration files

terraform fmt

Validate configuration

terraform validate

Show possible changes before applying:

terraform plan

Apply changes:

terraform apply

Inspect state of configuration

terraform show

Terraform Configuration files

The main config files are the main.tf and variables.tf files

main.tf

The main.tf contains the main configuration about the build you are creating. The first bit of info in the file is the terraform provider. This is a block of code describing the service that terraform will be building on (AWS, Azure, vSphere etc). It will also contain the info to login to the service.

for the vsphere provider:

provider "vsphere" {
   user           = "${var.vsphere_user}"
  password       = "${var.vsphere_password}"
  vsphere_server = "${var.vsphere_server}"
  allow_unverified_ssl = true
}

data block

In the main file you will place data blocks to describe the infrastructure. this will be used to get the info when building the resources.

You will see the two arguments in the data block, the first describes what type of data it is (this is an object in the terraform provider) and the second is the name which can be used to reference the data elsewhere in the config

In the compute cluster data block you can see it is looking at the earlier data block by using the data.vsphere_datacenter.datacenter description

data "vsphere_datacenter" "datacenter" {
  name = "<Datacenter name>"
}

data "vsphere_compute_cluster" "cluster" {
  name          = "<Cluster name>"
  datacenter_id = data.vsphere_datacenter.datacenter.id
}

data "vsphere_datastore" "datastore" {
  name          = "${var.vsphere_datastore}"
  datacenter_id = data.vsphere_datacenter.datacenter.id
}

data "vsphere_network" "network" {
  name          = "${var.vsphere_network}"
  datacenter_id = data.vsphere_datacenter.datacenter.id
}

variables.tf

This file will contain the variables for the main.tf file. This way it is easier to do different builds using the same main file.

example of the variable code block for the vsphere provider variables:

variable "vsphere_user" {
  description = "Username for vSphere"
  default = "<username>"
}

variable "vsphere_password" {
  description = "Password for vSphere"
  default = "<password>"
}

variable "vsphere_server" {
  description = "vSphere server address"
  default     = "<FQDN of vCenter server>"
}

Clone from template

When building templates make sure you add the "firmware" option to the "vsphere_virtual_machine" resource. This needs to be set to "efi" if the template is built with an efi firmware. By default the clone does not apply the same firmware as the template.