How to reference variables?

Difficulty: unrated

Answer

Variable are referenced with var.VARIABLE_NAME syntax. Let's have a look at an example:

vars.tf:

variable "memory" {
  type = string
  default "8192"
}

variable "cpu" {
  type = string
  default = "4"
}

main.tf:

resource "libvirt_domain" "vm1" {
   name = "vm1"
   memory = var.memory
   cpu = var.cpu
}