Uses reserved ip address.

main.tf

@@ -70,6 +70,12 @@ resource "digitalocean_custom_image" "flatcar" {
   regions = [var.datacenter]
 }
 
+resource "digitalocean_reserved_ip" "machine" {
+  for_each  = toset(var.machines)
+  # droplet_id = digitalocean_droplet.machine[each.key].id
+  region     = digitalocean_droplet.machine[each.key].region
+}
+
 resource "digitalocean_droplet" "machine" {
   for_each  = toset(var.machines)
   name      = "${var.cluster_name}-${each.key}"
@@ -83,6 +89,12 @@ resource "digitalocean_droplet" "machine" {
   }
 }
 
+resource "digitalocean_reserved_ip_assignment" "machine" {
+  for_each  = toset(var.machines)
+  ip_address = digitalocean_reserved_ip.machine[each.key].ip_address
+  droplet_id = digitalocean_droplet.machine[each.key].id
+}
+
 data "ct_config" "machine-ignitions" {
   for_each = toset(var.machines)
   content = templatefile("${path.module}/cl/machine-${each.key}.yaml.tmpl", {
@@ -98,3 +110,10 @@ output "ip-addresses" {
     "${var.cluster_name}-${key}" => digitalocean_droplet.machine[key].ipv4_address
   }
 }
+
+output "reserved-ip-addresses" {
+  value = {
+    for key in var.machines :
+    "${var.cluster_name}-${key}" => digitalocean_reserved_ip.machine[key].ip_address
+  }
+}