tf-libvirt/vms/main.tf

# tf provider declaration
terraform {
  # required_version = ">= 0.13"
  required_providers {
    libvirt = {
      source  = "dmacvicar/libvirt"
      version = "0.6.3"
    }
  }
}

# provider URI for libvirt
provider "libvirt" {
  uri = "qemu:///system"
}

# server settings are defined in terraform.tfvars
# the variables here are the defaults in case no relevant terraform.tfvars setting is found
variable "projectname" {
  type    = string
  default = "vms"
}
variable "hosts" {
  default = {
    "vm1" = {
      name     = "vm1",
      vcpu     = 1,
      memory   = "1024",
      diskpool = "default",
      disksize = "4000000000",
      mac      = "12:12:00:12:12:00",
    },
  }
}
variable "baseimagediskpool" {
  type    = string
  default = "default"
}
variable "domainname" {
  type    = string
  default = "domain.local"
}
variable "networkname" {
  type    = string
  default = "default"
}
variable "sourceimage" {
  type    = string
  default = "https://download.fedoraproject.org/pub/fedora/linux/releases/33/Cloud/x86_64/images/Fedora-Cloud-Base-33-1.2.x86_64.qcow2"
}
variable "category" {
  type    = string
  default = "host"
}

# base OS image
resource "libvirt_volume" "baseosimage" {
  for_each = var.hosts
  # if desired, base image could be specified for a category of devices sharing
  # the base image using name = "baseosimage_${var.projectname}.${each.value.category}"
  name   = "baseosimage_${var.projectname}.${each.value.name}"
  source = each.value.sourceimage
  pool   = var.baseimagediskpool
}

# vdisk creation
# vdisks are cloned from the base image for each of the "hosts"
resource "libvirt_volume" "qcow2_volume" {
  for_each = var.hosts
  name     = "${each.value.name}.qcow2"
  # let each baseos image have a name after the vm using it
  base_volume_id = libvirt_volume.baseosimage[each.value.name].id
  pool           = each.value.diskpool
  # currently a hard constraint to only use qcow2, could become settable
  format = "qcow2"
  size   = each.value.disksize
}

# Use cloudinit config file
# pass certain vars to cloudinit
data "template_file" "user_data" {
  for_each = var.hosts
  template = file("${path.module}/cloudinit.${each.value.category}.cfg")
  vars = {
    hostname   = each.value.name
    domainname = var.domainname
  }
}

# cloudinit magic
resource "libvirt_cloudinit_disk" "commoninit" {
  for_each  = var.hosts
  name      = "commoninit_${each.value.name}.iso"
  user_data = data.template_file.user_data[each.key].rendered
}

# net-lab domains loop
resource "libvirt_domain" "net-lab" {
  for_each = var.hosts
  name     = each.value.name
  cpu = {
    mode = "host-passthrough"
  }
  vcpu   = each.value.vcpu
  memory = each.value.memory

  network_interface {
    network_name = var.networkname
    mac          = each.value.mac
    # do not wait for a lease if networkname == "host-bridge"
    wait_for_lease = var.networkname == "host-bridge" ? false : true
  }

  disk {
    volume_id = element(libvirt_volume.qcow2_volume[each.key].*.id, 1)
  }

  cloudinit = libvirt_cloudinit_disk.commoninit[each.value.name].id

}


output "hostnames" {
  value = [libvirt_domain.net-lab.*]
}