fixing issue where the scale set fails to deploy on the first attempt…

… due to the load balancer health probes not being available before the scale set is created.

Also removed the nat gateway as it shouldn't be necessary

load_balancer.tf

@@ -42,6 +42,7 @@ resource "azurerm_lb_rule" "monitoring_vxlan_lb_rule" {
   backend_address_pool_ids = [
     azurerm_lb_backend_address_pool.monitoring_pool.id
   ]
+  probe_id = azurerm_lb_probe.sensor_health_check_probe.id
 }
 
 resource "azurerm_lb_rule" "monitoring_geneve_lb_rule" {
@@ -54,6 +55,7 @@ resource "azurerm_lb_rule" "monitoring_geneve_lb_rule" {
   backend_address_pool_ids = [
     azurerm_lb_backend_address_pool.monitoring_pool.id
   ]
+  probe_id = azurerm_lb_probe.sensor_health_check_probe.id
 }
 
 resource "azurerm_lb_rule" "monitoring_health_check_rule" {
@@ -79,4 +81,5 @@ resource "azurerm_lb_rule" "management_lb_rule" {
   backend_address_pool_ids = [
     azurerm_lb_backend_address_pool.management_pool.id
   ]
+  probe_id = azurerm_lb_probe.sensor_health_check_probe.id
 }

outputs.tf

@@ -2,14 +2,6 @@ output "internal_load_balancer_name" {
   value = azurerm_lb.scale_set_lb.name
 }
 
-output "nat_gateway_public_ip_name" {
-  value = azurerm_public_ip.nat_gw_ip.name
-}
-
-output "nat_gateway_name" {
-  value = azurerm_nat_gateway.lb_nat_gw.name
-}
-
 output "sensor_identity_principal_id" {
   value = azurerm_linux_virtual_machine_scale_set.sensor_scale_set.identity[0].principal_id
 }

scale_set.tf

@@ -24,6 +24,8 @@ resource "azurerm_linux_virtual_machine_scale_set" "sensor_scale_set" {
   }
 
   health_probe_id = azurerm_lb_probe.sensor_health_check_probe.id
+  upgrade_mode    = "Automatic"
+
   network_interface {
     name    = "management-nic"
     primary = true
@@ -51,6 +53,10 @@ resource "azurerm_linux_virtual_machine_scale_set" "sensor_scale_set" {
   }
 
   tags = var.tags
+
+  depends_on = [
+    azurerm_lb_rule.monitoring_health_check_rule,
+  ]
 }
 
 resource "azurerm_monitor_autoscale_setting" "auto_scale_config" {

variables.tf

@@ -57,18 +57,6 @@ variable "sensor_admin_username" {
   default     = "corelight"
 }
 
-variable "nat_gateway_ip_name" {
-  description = "The resource name of the VMSS NAT Gateway public IP resource"
-  type        = string
-  default     = "cl-nat-gw-ip"
-}
-
-variable "nat_gateway_name" {
-  description = "The resource name of the VMSS NAT Gateway resource"
-  type        = string
-  default     = "cl-sensor-nat-gw"
-}
-
 variable "autoscale_setting_name" {
   description = "The VMSS autoscale monitor name"
   type        = string