terraform notes: provision a server with tailscale automatically

tailscale.tf

terraform {
  required_providers {
    tailscale = {
      source  = "tailscale/tailscale"
      version = "0.13.7"
    }
  }
}

provider "tailscale" {
  api_key = var.TAILSCALE_API_KEY
  tailnet = "[email protected]" # username
}

variable "TAILSCALE_API_KEY" {}

resource "tailscale_tailnet_key" "setup_key" {
  reusable      = true
  ephemeral     = false
  preauthorized = false
  expiry        = 600
}

resource "vultr_instance" "web" {
  plan        = "vc2-1c-0.5gb"
  region      = "ewr"
  os_id       = 477
  enable_ipv6 = true
  user_data = <<-EOT
    #cloud-config
    apt:
      sources:
        tailscale.list:
          source: deb https://pkgs.tailscale.com/stable/ubuntu focal main
          keyid: 2596A99EAAB33821893C0A79458CA832957F5868
    package_update: true
    package_upgrade: true

    packages:
      - tailscale

    runcmd:
      - [tailscale, up, -authkey, ${tailscale_tailnet_key.setup_key.key}]
      - ufw allow in on tailscale0

  EOT
  hostname = "webserver"
}