Merge pull request #483 from alphagov/auth-1316-ecs-sizing

AUTH-1316: Bring ECS sizing in line with PaaS deployment

Author: chrisclayson

ci/terraform/ecs.tf

@@ -10,6 +10,9 @@ resource "aws_ecs_service" "frontend_ecs_service" {
   desired_count   = var.ecs_desired_count
   launch_type     = "FARGATE"
 
+  deployment_minimum_healthy_percent = var.deployment_min_healthy_percent
+  deployment_maximum_percent         = var.deployment_max_percent
+
   network_configuration {
     security_groups = [
       local.allow_egress_security_group_id,

ci/terraform/production.tfvars

@@ -1,4 +1,5 @@
 redis_service_plan  = "large-ha-5_x"
 environment         = "production"
 common_state_bucket = "digital-identity-prod-tfstate"
-public_access       = false
+public_access       = false
+ecs_desired_count   = 4

ci/terraform/variables.tf

@@ -82,7 +82,7 @@ variable "image_digest" {
 
 variable "ecs_desired_count" {
   type    = number
-  default = 3
+  default = 2
 }
 
 variable "app_port" {
@@ -135,4 +135,12 @@ variable "zendesk_api_token" {
 
 variable "frontend_api_fqdn" {
   default = null
+}
+
+variable "deployment_min_healthy_percent" {
+  default = 50
+}
+
+variable "deployment_max_percent" {
+  default = 100
 }