Terraform is an infrastructure as code tool that lets you build, change, and version infrastructure safely and efficiently. This includes low-level components like compute instances, storage, and networking; and high-level components like DNS entries and SaaS features.

I use Terraform to manage infrastructure and development environments in my homelab. I’ve used a variety of providers, primarily proxmox1, docker2, and coder3.

Proxmox

One of the main tasks I solve with Terraform is creation and desctruction of virtual machines in Proxmox.

Most common arguments are abstracted out to a child module in the slab project. Default values get set there. In the past I’ve maintained this module in a private Terraform registry, but that was cumbersome to maintain and harder to document and reason about.

Today for example, to create a new virtual machine with 8GB of ram and 8 CPU cores, I would add this block to my main.tf file.

module "ubuvm" {
  count  = 1
  source = "./modules/ubuntu-vm"

  name            = "newdevbox"
  vmid            = 120
  cores           = 8
  mem             = 8196
  ip_address      = "10.1.100.100"
}

Memorable Challenges

  • Manage state in Terraform Cloud.
  • Manage Plan/Apply workflow in Terraform Cloud.
  • Use as a step in Gitlab and Jenkins pipelines.
  • Orchestrate Docker containers on a variety of hosts.
  • Migrating from a locally managed state to using a remote backend in Terraform Cloud.
  • Borking my workflow by upgrading to a new version of the Proxmox provider that was incompatible with my current version of Terraform.
  • Manually copying and pasting resource definitions into / out of state files.

  1. Proxmox Provider ↩

  2. Docker Provider ↩

  3. Coder Provider ↩