From e59c206a95ab8e701437b53c94cbdff5591082c1 Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 17:42:40 +0900
Subject: [PATCH 1/9] =?UTF-8?q?chore:=20=EB=A1=9C=EB=93=9C=EB=B0=B8?=
 =?UTF-8?q?=EB=9F=B0=EC=84=9C=20=EC=A0=91=EA=B7=BC=EB=B0=A9=EC=8B=9D=20?=
 =?UTF-8?q?=EB=B0=8F=20=EC=BB=B4=ED=93=A8=ED=8A=B8=20=EC=9A=A9=EB=9F=89=20?=
 =?UTF-8?q?=EC=88=98=EC=A0=95=20(#5)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 terraform/environments/prod/compute.tf       |  4 ++--
 terraform/environments/prod/load-balancer.tf | 14 +++++++++-----
 terraform/environments/prod/variables.tf     | 18 ++++++++++++++++++
 terraform/modules/load-balancer/main.tf      |  9 +++++++++
 terraform/modules/load-balancer/variables.tf |  7 ++++++-
 5 files changed, 44 insertions(+), 8 deletions(-)

diff --git a/terraform/environments/prod/compute.tf b/terraform/environments/prod/compute.tf
index 83dbf16..71aeedb 100644
--- a/terraform/environments/prod/compute.tf
+++ b/terraform/environments/prod/compute.tf
@@ -52,8 +52,8 @@ module "web_servers" {
   # 공통 인스턴스 설정
   machine_type       = var.web_machine_type
   source_image       = var.web_source_image
-  boot_disk_size_gb  = 50
-  boot_disk_type     = "pd-ssd" # 프로덕션 환경은 SSD 디스크를 사용합니다.
+  boot_disk_size_gb  = var.web_machine_ssd
+  boot_disk_type     = "pd-ssd"
   enable_external_ip = false
   tags               = ["web-server", var.environment]
   labels = {
diff --git a/terraform/environments/prod/load-balancer.tf b/terraform/environments/prod/load-balancer.tf
index e357df1..10638c2 100644
--- a/terraform/environments/prod/load-balancer.tf
+++ b/terraform/environments/prod/load-balancer.tf
@@ -25,11 +25,15 @@ module "load_balancer" {
   backend_timeout_sec = 30
   session_affinity    = "CLIENT_IP"
   backend_groups = var.use_instance_group ? [
-    {
-      group           = module.web_servers.instance_group_instance_group
-      balancing_mode  = "UTILIZATION"
-      max_utilization = 0.8
-    }
+    merge(
+      {
+        group          = module.web_servers.instance_group_instance_group
+        balancing_mode = var.lb_type == "NETWORK" ? "CONNECTION" : "UTILIZATION"
+      },
+      var.lb_type == "NETWORK" ? {} : {
+        max_utilization = 0.8
+      }
+    )
   ] : []
   ssl_certificates = var.ssl_certificates
 
diff --git a/terraform/environments/prod/variables.tf b/terraform/environments/prod/variables.tf
index a13fe2c..c5d02c6 100644
--- a/terraform/environments/prod/variables.tf
+++ b/terraform/environments/prod/variables.tf
@@ -91,6 +91,12 @@ variable "web_machine_type" {
   default     = "e2-standard-2" # 운영 환경에 맞춘 고성능 인스턴스입니다.
 }
 
+variable "web_machine_ssd" {
+  description = "웹 서버에 사용할 머신 용량입니다."
+  type        = number
+  default     = 30
+}
+
 variable "web_source_image" {
   description = "웹 서버 부팅 디스크에 사용할 이미지입니다."
   type        = string
@@ -144,3 +150,15 @@ variable "ssl_certificates" {
   type        = list(string)
   default     = []
 }
+
+# Tags
+variable "common_tags" {
+  description = "공통 태그입니다."
+  type        = map(string)
+  default = {
+    Project     = "pinhouse"
+    Environment = "prod"
+    Version     = "v1"
+    ManagedBy   = "Terraform"
+  }
+}
diff --git a/terraform/modules/load-balancer/main.tf b/terraform/modules/load-balancer/main.tf
index e0b5c71..907d218 100644
--- a/terraform/modules/load-balancer/main.tf
+++ b/terraform/modules/load-balancer/main.tf
@@ -127,6 +127,15 @@ resource "google_compute_region_backend_service" "backend_service" {
 
   # 선택적으로 연결 드레이닝 타임아웃을 적용합니다.
   connection_draining_timeout_sec = var.connection_draining_timeout
+
+  lifecycle {
+    precondition {
+      condition = alltrue([
+        for backend in var.backend_groups : lookup(backend, "balancing_mode", "CONNECTION") == "CONNECTION"
+      ])
+      error_message = "NETWORK 로드 밸런서의 backend_groups balancing_mode는 CONNECTION만 사용할 수 있습니다."
+    }
+  }
 }
 
 # ========================================
diff --git a/terraform/modules/load-balancer/variables.tf b/terraform/modules/load-balancer/variables.tf
index da8833d..581b1eb 100644
--- a/terraform/modules/load-balancer/variables.tf
+++ b/terraform/modules/load-balancer/variables.tf
@@ -84,9 +84,14 @@ variable "health_check_ids" {
 # 백엔드 서비스 변수
 # ========================================
 variable "backend_protocol" {
-  description = "백엔드 서비스 프로토콜입니다. TCP, UDP, SSL 중 하나를 사용합니다."
+  description = "백엔드 서비스 프로토콜입니다. TCP, UDP, UNSPECIFIED 중 하나를 사용합니다."
   type        = string
   default     = "TCP"
+
+  validation {
+    condition     = contains(["TCP", "UDP", "UNSPECIFIED"], var.backend_protocol)
+    error_message = "backend_protocol은 TCP, UDP, UNSPECIFIED 중 하나여야 합니다."
+  }
 }
 
 variable "backend_timeout_sec" {

From 4f889f7b5e71e9502ee4bf5d4da672fc834a97c9 Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 17:53:10 +0900
Subject: [PATCH 2/9] =?UTF-8?q?style:=20=ED=85=8C=EB=9D=BC=ED=8F=BC=20?=
 =?UTF-8?q?=EA=B3=B5=ED=86=B5=20=ED=83=9C=EA=B7=B8=20=EC=A0=81=EC=9A=A9=20?=
 =?UTF-8?q?(#5)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 terraform/environments/prod/compute.tf        | 35 ++++++-------------
 .../prod/terraform.tfvars.example             |  2 +-
 terraform/environments/prod/variables.tf      | 18 +++++-----
 terraform/modules/compute/main.tf             | 23 ++++++++----
 terraform/modules/compute/variables.tf        |  6 ++--
 terraform/modules/nat-instance/main.tf        |  6 ++--
 terraform/modules/nat-instance/variables.tf   |  4 +--
 terraform/modules/storage/main.tf             | 10 ++++--
 terraform/modules/storage/variables.tf        |  6 ++--
 9 files changed, 56 insertions(+), 54 deletions(-)

diff --git a/terraform/environments/prod/compute.tf b/terraform/environments/prod/compute.tf
index 71aeedb..9868db6 100644
--- a/terraform/environments/prod/compute.tf
+++ b/terraform/environments/prod/compute.tf
@@ -24,29 +24,13 @@ module "web_servers" {
   # 관리형 인스턴스 그룹을 사용하지 않을 때만 개별 인스턴스를 정의합니다.
   instances = !var.use_instance_group && var.create_web_instances ? tomap({
     web1 = {
-      name               = "${var.environment}-web-01"
-      zone               = "${var.region}-a"
-      machine_type       = var.web_machine_type
-      enable_external_ip = false # 프로덕션 환경은 로드 밸런서를 통한 접근만 허용합니다.
-      tags               = ["web-server", var.environment]
-      labels = {
-        environment = var.environment
-        role        = "web"
-      }
+      name                = "${var.environment}-web-01"
+      zone                = "${var.region}-a"
+      machine_type        = var.web_machine_type
+      enable_external_ip  = false # 프로덕션 환경은 로드 밸런서를 통한 접근만 허용합니다.
+      tags                = ["web-server", var.environment]
       deletion_protection = true # 실수로 삭제되지 않도록 보호합니다.
     }
-    web2 = {
-      name               = "${var.environment}-web-02"
-      zone               = "${var.region}-b"
-      machine_type       = var.web_machine_type
-      enable_external_ip = false
-      tags               = ["web-server", var.environment]
-      labels = {
-        environment = var.environment
-        role        = "web"
-      }
-      deletion_protection = true
-    }
   }) : tomap({})
 
   # 공통 인스턴스 설정
@@ -56,10 +40,11 @@ module "web_servers" {
   boot_disk_type     = "pd-ssd"
   enable_external_ip = false
   tags               = ["web-server", var.environment]
-  labels = {
-    environment = var.environment
-    role        = "web"
-  }
+
+  # 태그
+  common_tags = merge(var.common_tags, {
+    Service = "Backend"
+  })
 
   # 서비스 계정 설정
   service_account_email = var.service_account_email
diff --git a/terraform/environments/prod/terraform.tfvars.example b/terraform/environments/prod/terraform.tfvars.example
index b98ede3..0180814 100644
--- a/terraform/environments/prod/terraform.tfvars.example
+++ b/terraform/environments/prod/terraform.tfvars.example
@@ -30,7 +30,7 @@ autoscaling_max_replicas = 5
 
 web_machine_type = "e2-standard-2"
 web_source_image = "ubuntu-os-cloud/ubuntu-2204-lts"
-
+web_machine_ssd  = 30
 # ========================================
 # 스토리지 관련 값
 # ========================================
diff --git a/terraform/environments/prod/variables.tf b/terraform/environments/prod/variables.tf
index c5d02c6..6e0db8a 100644
--- a/terraform/environments/prod/variables.tf
+++ b/terraform/environments/prod/variables.tf
@@ -64,7 +64,7 @@ variable "create_web_instances" {
 variable "instance_group_size" {
   description = "관리형 인스턴스 그룹의 목표 인스턴스 수입니다."
   type        = number
-  default     = 2
+  default     = 1
 }
 
 variable "enable_autoscaling" {
@@ -76,7 +76,7 @@ variable "enable_autoscaling" {
 variable "autoscaling_min_replicas" {
   description = "오토스케일링 최소 인스턴스 수입니다."
   type        = number
-  default     = 2
+  default     = 1
 }
 
 variable "autoscaling_max_replicas" {
@@ -121,7 +121,7 @@ variable "create_storage_buckets" {
 variable "storage_location" {
   description = "스토리지 버킷을 생성할 위치입니다."
   type        = string
-  default     = "ASIA" # 운영 환경에서는 멀티 리전을 기본값으로 사용합니다.
+  default     = "ASIA-NORTHEAST3" # 비용 절감을 위해 단일 리전을 기본값으로 사용합니다.
 }
 
 variable "allowed_cors_origins" {
@@ -151,14 +151,16 @@ variable "ssl_certificates" {
   default     = []
 }
 
-# Tags
+# ========================================
+# 공통 태그 변수
+# ========================================
 variable "common_tags" {
   description = "공통 태그입니다."
   type        = map(string)
   default = {
-    Project     = "pinhouse"
-    Environment = "prod"
-    Version     = "v1"
-    ManagedBy   = "Terraform"
+    project     = "pinhouse"
+    environment = "prod"
+    version     = "v1"
+    managed_by  = "terraform"
   }
 }
diff --git a/terraform/modules/compute/main.tf b/terraform/modules/compute/main.tf
index a639930..ed50b39 100644
--- a/terraform/modules/compute/main.tf
+++ b/terraform/modules/compute/main.tf
@@ -52,8 +52,10 @@ resource "google_compute_instance_template" "template" {
   # 네트워크 태그입니다.
   tags = var.tags
 
-  # 공통 레이블입니다.
-  labels = var.labels
+  # 공통 태그를 GCP 레이블에 반영합니다.
+  labels = {
+    for k, v in var.common_tags : lower(k) => lower(v)
+  }
 
   # 선점형 인스턴스일 때 스케줄링 정책을 조정합니다.
   scheduling {
@@ -107,11 +109,11 @@ resource "google_compute_instance" "instances" {
       enable-oslogin = var.enable_os_login
     },
     var.metadata,
-    lookup(each.value, "metadata", {})
+    coalesce(lookup(each.value, "metadata", null), {})
   )
 
   # 인스턴스별 시작 스크립트를 우선 적용합니다.
-  metadata_startup_script = lookup(each.value, "startup_script", var.startup_script)
+  metadata_startup_script = coalesce(lookup(each.value, "startup_script", null), var.startup_script)
 
   # 서비스 계정 설정입니다.
   service_account {
@@ -120,10 +122,17 @@ resource "google_compute_instance" "instances" {
   }
 
   # 공통 태그와 인스턴스별 태그를 합칩니다.
-  tags = concat(var.tags, lookup(each.value, "tags", []))
+  tags = concat(var.tags, coalesce(lookup(each.value, "tags", null), []))
 
-  # 공통 레이블과 인스턴스별 레이블을 합칩니다.
-  labels = merge(var.labels, lookup(each.value, "labels", {}))
+  # 공통 태그와 인스턴스별 태그 맵을 GCP 레이블에 반영합니다.
+  labels = merge(
+    {
+      for k, v in var.common_tags : lower(k) => lower(v)
+    },
+    {
+      for k, v in coalesce(lookup(each.value, "common_tags", null), {}) : lower(k) => lower(v)
+    }
+  )
 
   # 선점형 여부에 따라 스케줄링 정책을 조정합니다.
   scheduling {
diff --git a/terraform/modules/compute/variables.tf b/terraform/modules/compute/variables.tf
index 25975d5..2c4ec06 100644
--- a/terraform/modules/compute/variables.tf
+++ b/terraform/modules/compute/variables.tf
@@ -109,8 +109,8 @@ variable "tags" {
   default     = []
 }
 
-variable "labels" {
-  description = "인스턴스에 적용할 공통 레이블입니다."
+variable "common_tags" {
+  description = "인스턴스에 적용할 공통 태그입니다."
   type        = map(string)
   default     = {}
 }
@@ -135,7 +135,7 @@ variable "instances" {
     metadata            = optional(map(string))
     startup_script      = optional(string)
     tags                = optional(list(string))
-    labels              = optional(map(string))
+    common_tags         = optional(map(string))
     deletion_protection = optional(bool)
   }))
   default = {}
diff --git a/terraform/modules/nat-instance/main.tf b/terraform/modules/nat-instance/main.tf
index 5412a66..9dd8e8f 100644
--- a/terraform/modules/nat-instance/main.tf
+++ b/terraform/modules/nat-instance/main.tf
@@ -60,8 +60,10 @@ resource "google_compute_instance" "nat_instance" {
     }
   }
 
-  tags   = concat(var.tags, [var.nat_instance_tag])
-  labels = var.labels
+  tags = concat(var.tags, [var.nat_instance_tag])
+  labels = {
+    for k, v in var.common_tags : lower(k) => lower(v)
+  }
 
   allow_stopping_for_update = true
 }
diff --git a/terraform/modules/nat-instance/variables.tf b/terraform/modules/nat-instance/variables.tf
index 0caab88..06912ea 100644
--- a/terraform/modules/nat-instance/variables.tf
+++ b/terraform/modules/nat-instance/variables.tf
@@ -105,8 +105,8 @@ variable "tags" {
   default     = []
 }
 
-variable "labels" {
-  description = "NAT 인스턴스에 부여할 레이블입니다."
+variable "common_tags" {
+  description = "NAT 인스턴스에 부여할 공통 태그입니다."
   type        = map(string)
   default     = {}
 }
diff --git a/terraform/modules/storage/main.tf b/terraform/modules/storage/main.tf
index 0f8414b..cba1fc3 100644
--- a/terraform/modules/storage/main.tf
+++ b/terraform/modules/storage/main.tf
@@ -11,10 +11,14 @@ resource "google_storage_bucket" "buckets" {
   # 버킷이 생성될 프로젝트입니다.
   project = var.project_id
 
-  # 기본 레이블과 버킷별 레이블을 병합합니다.
+  # 기본 태그와 버킷별 태그를 GCP 레이블에 반영합니다.
   labels = merge(
-    var.default_labels,
-    lookup(each.value, "labels", {})
+    {
+      for k, v in var.common_tags : lower(k) => lower(v)
+    },
+    {
+      for k, v in coalesce(lookup(each.value, "common_tags", null), {}) : lower(k) => lower(v)
+    }
   )
 
   # 균일한 버킷 수준 액세스 설정입니다.
diff --git a/terraform/modules/storage/variables.tf b/terraform/modules/storage/variables.tf
index 6e77f53..83bf49b 100644
--- a/terraform/modules/storage/variables.tf
+++ b/terraform/modules/storage/variables.tf
@@ -23,8 +23,8 @@ variable "default_storage_class" {
   }
 }
 
-variable "default_labels" {
-  description = "모든 버킷에 공통 적용할 레이블입니다."
+variable "common_tags" {
+  description = "모든 버킷에 공통 적용할 태그입니다."
   type        = map(string)
   default     = {}
 }
@@ -38,7 +38,7 @@ variable "buckets" {
     name                        = string
     location                    = optional(string)
     storage_class               = optional(string)
-    labels                      = optional(map(string))
+    common_tags                 = optional(map(string))
     uniform_bucket_level_access = optional(bool)
     versioning_enabled          = optional(bool)
     force_destroy               = optional(bool)

From d4f0309947594cdba36e830b9f1fea917be182b0 Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 17:55:10 +0900
Subject: [PATCH 3/9] =?UTF-8?q?chore:=20=EB=8B=A8=EC=9D=BC=20=EB=A1=9C?=
 =?UTF-8?q?=EB=93=9C=20=EB=B0=B8=EB=9F=B0=EC=84=9C=20=EC=A0=81=EC=9A=A9=20?=
 =?UTF-8?q?(#7)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 terraform/environments/prod/vpc.tf | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/terraform/environments/prod/vpc.tf b/terraform/environments/prod/vpc.tf
index f43d0f4..a874a2c 100644
--- a/terraform/environments/prod/vpc.tf
+++ b/terraform/environments/prod/vpc.tf
@@ -6,7 +6,7 @@ module "vpc" {
 
   vpc_name     = "${var.project}-${var.environment}-vpc"
   description  = "프로덕션 환경용 VPC 네트워크"
-  routing_mode = "GLOBAL"
+  routing_mode = "REGIONAL"
 
   # 서브넷 정의
   subnets = {

From 5b5c4565541c3f48a6963ba77b712f5afd708ab4 Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 17:55:34 +0900
Subject: [PATCH 4/9] =?UTF-8?q?fix:=20=EA=B3=B5=ED=86=B5=20=ED=83=9C?=
 =?UTF-8?q?=EA=B7=B8=20=EB=B0=8F=20=EB=A1=9C=EA=B7=B8=20=EB=B2=84=ED=82=B7?=
 =?UTF-8?q?=20=EC=A0=9C=EA=B1=B0=20(#7)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 terraform/environments/prod/storage.tf | 65 +++-----------------------
 1 file changed, 6 insertions(+), 59 deletions(-)

diff --git a/terraform/environments/prod/storage.tf b/terraform/environments/prod/storage.tf
index a893bfa..1b125e5 100644
--- a/terraform/environments/prod/storage.tf
+++ b/terraform/environments/prod/storage.tf
@@ -6,16 +6,17 @@ module "storage" {
 
   project_id       = var.project_id
   default_location = var.storage_location
-  default_labels = {
-    environment = var.environment
-    managed_by  = "terraform"
-  }
+
+  # 태그
+  common_tags = merge(var.common_tags, {
+    Service = "Storage"
+  })
 
   # 버킷 정의
   buckets = merge(
     var.create_storage_buckets ? tomap({
       static_assets = {
-        name                        = "${var.project_id}-${var.environment}-static-assets"
+        name                        = "${var.project_id}-${var.environment}"
         storage_class               = "STANDARD"
         uniform_bucket_level_access = true
         versioning_enabled          = true
@@ -45,60 +46,6 @@ module "storage" {
           }
         ] : []
       }
-    }) : tomap({}),
-    var.create_storage_buckets ? tomap({
-      backups = {
-        name                        = "${var.project_id}-${var.environment}-backups"
-        storage_class               = "NEARLINE"
-        uniform_bucket_level_access = true
-        versioning_enabled          = true
-        force_destroy               = false
-        public_access_prevention    = "enforced"
-
-        # 오래된 백업은 저장 등급을 낮추고 최종적으로 삭제합니다.
-        lifecycle_rules = [
-          {
-            action = {
-              type          = "SetStorageClass"
-              storage_class = "COLDLINE"
-            }
-            condition = {
-              age = 90
-            }
-          },
-          {
-            action = {
-              type = "Delete"
-            }
-            condition = {
-              age                = 365
-              num_newer_versions = 10
-            }
-          }
-        ]
-      }
-    }) : tomap({}),
-    var.create_storage_buckets ? tomap({
-      logs = {
-        name                        = "${var.project_id}-${var.environment}-logs"
-        storage_class               = "STANDARD"
-        uniform_bucket_level_access = true
-        versioning_enabled          = false
-        force_destroy               = false
-        public_access_prevention    = "enforced"
-
-        # 로그 버킷은 30일 이후 자동 삭제합니다.
-        lifecycle_rules = [
-          {
-            action = {
-              type = "Delete"
-            }
-            condition = {
-              age = 30
-            }
-          }
-        ]
-      }
     }) : tomap({})
   )
 }

From f8e075d4b3ddb7f6917702e774032adc692c1624 Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 18:04:51 +0900
Subject: [PATCH 5/9] =?UTF-8?q?style:=20=ED=85=8C=EB=9D=BC=ED=8F=BC=20?=
 =?UTF-8?q?=EA=B3=B5=ED=86=B5=20=ED=83=9C=EA=B7=B8=20=EC=A0=81=EC=9A=A9=20?=
 =?UTF-8?q?(#5)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 terraform/environments/prod/compute.tf      | 39 +++++++++------------
 terraform/environments/prod/variables.tf    | 20 +++++++++++
 terraform/modules/compute/main.tf           | 23 ++++++++----
 terraform/modules/compute/variables.tf      |  6 ++--
 terraform/modules/nat-instance/main.tf      |  6 ++--
 terraform/modules/nat-instance/variables.tf |  4 +--
 terraform/modules/storage/main.tf           | 10 ++++--
 terraform/modules/storage/variables.tf      |  6 ++--
 8 files changed, 71 insertions(+), 43 deletions(-)

diff --git a/terraform/environments/prod/compute.tf b/terraform/environments/prod/compute.tf
index 83dbf16..db6426f 100644
--- a/terraform/environments/prod/compute.tf
+++ b/terraform/environments/prod/compute.tf
@@ -24,27 +24,19 @@ module "web_servers" {
   # 관리형 인스턴스 그룹을 사용하지 않을 때만 개별 인스턴스를 정의합니다.
   instances = !var.use_instance_group && var.create_web_instances ? tomap({
     web1 = {
-      name               = "${var.environment}-web-01"
-      zone               = "${var.region}-a"
-      machine_type       = var.web_machine_type
-      enable_external_ip = false # 프로덕션 환경은 로드 밸런서를 통한 접근만 허용합니다.
-      tags               = ["web-server", var.environment]
-      labels = {
-        environment = var.environment
-        role        = "web"
-      }
+      name                = "${var.environment}-web-01"
+      zone                = "${var.region}-a"
+      machine_type        = var.web_machine_type
+      enable_external_ip  = false # 프로덕션 환경은 로드 밸런서를 통한 접근만 허용합니다.
+      tags                = ["web-server", var.environment]
       deletion_protection = true # 실수로 삭제되지 않도록 보호합니다.
     }
     web2 = {
-      name               = "${var.environment}-web-02"
-      zone               = "${var.region}-b"
-      machine_type       = var.web_machine_type
-      enable_external_ip = false
-      tags               = ["web-server", var.environment]
-      labels = {
-        environment = var.environment
-        role        = "web"
-      }
+      name                = "${var.environment}-web-02"
+      zone                = "${var.region}-b"
+      machine_type        = var.web_machine_type
+      enable_external_ip  = false
+      tags                = ["web-server", var.environment]
       deletion_protection = true
     }
   }) : tomap({})
@@ -52,14 +44,15 @@ module "web_servers" {
   # 공통 인스턴스 설정
   machine_type       = var.web_machine_type
   source_image       = var.web_source_image
-  boot_disk_size_gb  = 50
+  boot_disk_size_gb  = var.web_machine_ssd
   boot_disk_type     = "pd-ssd" # 프로덕션 환경은 SSD 디스크를 사용합니다.
   enable_external_ip = false
   tags               = ["web-server", var.environment]
-  labels = {
-    environment = var.environment
-    role        = "web"
-  }
+
+  # 태그
+  common_tags = merge(var.common_tags, {
+    Service = "Backend"
+  })
 
   # 서비스 계정 설정
   service_account_email = var.service_account_email
diff --git a/terraform/environments/prod/variables.tf b/terraform/environments/prod/variables.tf
index a13fe2c..1024448 100644
--- a/terraform/environments/prod/variables.tf
+++ b/terraform/environments/prod/variables.tf
@@ -91,6 +91,12 @@ variable "web_machine_type" {
   default     = "e2-standard-2" # 운영 환경에 맞춘 고성능 인스턴스입니다.
 }
 
+variable "web_machine_ssd" {
+  description = "웹 서버 부팅 디스크 크기(GB)입니다."
+  type        = number
+  default     = 50
+}
+
 variable "web_source_image" {
   description = "웹 서버 부팅 디스크에 사용할 이미지입니다."
   type        = string
@@ -144,3 +150,17 @@ variable "ssl_certificates" {
   type        = list(string)
   default     = []
 }
+
+# ========================================
+# 공통 태그 변수
+# ========================================
+variable "common_tags" {
+  description = "공통 태그입니다."
+  type        = map(string)
+  default = {
+    Project     = "pinhouse"
+    Environment = "prod"
+    Version     = "v1"
+    ManagedBy   = "Terraform"
+  }
+}
diff --git a/terraform/modules/compute/main.tf b/terraform/modules/compute/main.tf
index a639930..ed50b39 100644
--- a/terraform/modules/compute/main.tf
+++ b/terraform/modules/compute/main.tf
@@ -52,8 +52,10 @@ resource "google_compute_instance_template" "template" {
   # 네트워크 태그입니다.
   tags = var.tags
 
-  # 공통 레이블입니다.
-  labels = var.labels
+  # 공통 태그를 GCP 레이블에 반영합니다.
+  labels = {
+    for k, v in var.common_tags : lower(k) => lower(v)
+  }
 
   # 선점형 인스턴스일 때 스케줄링 정책을 조정합니다.
   scheduling {
@@ -107,11 +109,11 @@ resource "google_compute_instance" "instances" {
       enable-oslogin = var.enable_os_login
     },
     var.metadata,
-    lookup(each.value, "metadata", {})
+    coalesce(lookup(each.value, "metadata", null), {})
   )
 
   # 인스턴스별 시작 스크립트를 우선 적용합니다.
-  metadata_startup_script = lookup(each.value, "startup_script", var.startup_script)
+  metadata_startup_script = coalesce(lookup(each.value, "startup_script", null), var.startup_script)
 
   # 서비스 계정 설정입니다.
   service_account {
@@ -120,10 +122,17 @@ resource "google_compute_instance" "instances" {
   }
 
   # 공통 태그와 인스턴스별 태그를 합칩니다.
-  tags = concat(var.tags, lookup(each.value, "tags", []))
+  tags = concat(var.tags, coalesce(lookup(each.value, "tags", null), []))
 
-  # 공통 레이블과 인스턴스별 레이블을 합칩니다.
-  labels = merge(var.labels, lookup(each.value, "labels", {}))
+  # 공통 태그와 인스턴스별 태그 맵을 GCP 레이블에 반영합니다.
+  labels = merge(
+    {
+      for k, v in var.common_tags : lower(k) => lower(v)
+    },
+    {
+      for k, v in coalesce(lookup(each.value, "common_tags", null), {}) : lower(k) => lower(v)
+    }
+  )
 
   # 선점형 여부에 따라 스케줄링 정책을 조정합니다.
   scheduling {
diff --git a/terraform/modules/compute/variables.tf b/terraform/modules/compute/variables.tf
index 25975d5..2c4ec06 100644
--- a/terraform/modules/compute/variables.tf
+++ b/terraform/modules/compute/variables.tf
@@ -109,8 +109,8 @@ variable "tags" {
   default     = []
 }
 
-variable "labels" {
-  description = "인스턴스에 적용할 공통 레이블입니다."
+variable "common_tags" {
+  description = "인스턴스에 적용할 공통 태그입니다."
   type        = map(string)
   default     = {}
 }
@@ -135,7 +135,7 @@ variable "instances" {
     metadata            = optional(map(string))
     startup_script      = optional(string)
     tags                = optional(list(string))
-    labels              = optional(map(string))
+    common_tags         = optional(map(string))
     deletion_protection = optional(bool)
   }))
   default = {}
diff --git a/terraform/modules/nat-instance/main.tf b/terraform/modules/nat-instance/main.tf
index 5412a66..9dd8e8f 100644
--- a/terraform/modules/nat-instance/main.tf
+++ b/terraform/modules/nat-instance/main.tf
@@ -60,8 +60,10 @@ resource "google_compute_instance" "nat_instance" {
     }
   }
 
-  tags   = concat(var.tags, [var.nat_instance_tag])
-  labels = var.labels
+  tags = concat(var.tags, [var.nat_instance_tag])
+  labels = {
+    for k, v in var.common_tags : lower(k) => lower(v)
+  }
 
   allow_stopping_for_update = true
 }
diff --git a/terraform/modules/nat-instance/variables.tf b/terraform/modules/nat-instance/variables.tf
index 0caab88..06912ea 100644
--- a/terraform/modules/nat-instance/variables.tf
+++ b/terraform/modules/nat-instance/variables.tf
@@ -105,8 +105,8 @@ variable "tags" {
   default     = []
 }
 
-variable "labels" {
-  description = "NAT 인스턴스에 부여할 레이블입니다."
+variable "common_tags" {
+  description = "NAT 인스턴스에 부여할 공통 태그입니다."
   type        = map(string)
   default     = {}
 }
diff --git a/terraform/modules/storage/main.tf b/terraform/modules/storage/main.tf
index 0f8414b..cba1fc3 100644
--- a/terraform/modules/storage/main.tf
+++ b/terraform/modules/storage/main.tf
@@ -11,10 +11,14 @@ resource "google_storage_bucket" "buckets" {
   # 버킷이 생성될 프로젝트입니다.
   project = var.project_id
 
-  # 기본 레이블과 버킷별 레이블을 병합합니다.
+  # 기본 태그와 버킷별 태그를 GCP 레이블에 반영합니다.
   labels = merge(
-    var.default_labels,
-    lookup(each.value, "labels", {})
+    {
+      for k, v in var.common_tags : lower(k) => lower(v)
+    },
+    {
+      for k, v in coalesce(lookup(each.value, "common_tags", null), {}) : lower(k) => lower(v)
+    }
   )
 
   # 균일한 버킷 수준 액세스 설정입니다.
diff --git a/terraform/modules/storage/variables.tf b/terraform/modules/storage/variables.tf
index 6e77f53..83bf49b 100644
--- a/terraform/modules/storage/variables.tf
+++ b/terraform/modules/storage/variables.tf
@@ -23,8 +23,8 @@ variable "default_storage_class" {
   }
 }
 
-variable "default_labels" {
-  description = "모든 버킷에 공통 적용할 레이블입니다."
+variable "common_tags" {
+  description = "모든 버킷에 공통 적용할 태그입니다."
   type        = map(string)
   default     = {}
 }
@@ -38,7 +38,7 @@ variable "buckets" {
     name                        = string
     location                    = optional(string)
     storage_class               = optional(string)
-    labels                      = optional(map(string))
+    common_tags                 = optional(map(string))
     uniform_bucket_level_access = optional(bool)
     versioning_enabled          = optional(bool)
     force_destroy               = optional(bool)

From 2931d8222bc5c575887304603375eecf5d9928a2 Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 18:31:46 +0900
Subject: [PATCH 6/9] =?UTF-8?q?fix:=20PR=20=ED=8C=8C=EC=9D=B4=ED=94=84?=
 =?UTF-8?q?=EB=9D=BC=EC=9D=B8=20=EC=8A=A4=ED=82=B5=EB=90=98=EB=8A=94=20?=
 =?UTF-8?q?=EB=AC=B8=EC=A0=9C=20=EC=88=98=EC=A0=95=20(#7)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .github/workflows/terraform-plan.yml | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/.github/workflows/terraform-plan.yml b/.github/workflows/terraform-plan.yml
index 04a54ec..49b82c6 100644
--- a/.github/workflows/terraform-plan.yml
+++ b/.github/workflows/terraform-plan.yml
@@ -45,25 +45,22 @@ jobs:
           echo "변경된 파일 목록:"
           echo "$CHANGED_FILES"
 
-          # 변경된 환경을 JSON 배열 문자열로 수집합니다.
-          ENVIRONMENTS=""
-
-          # prod 환경 파일 변경 여부를 확인합니다.
+          # prod 환경 또는 공통 모듈 변경 시 prod 환경 Plan을 수행합니다.
+          ENVIRONMENTS='[]'
           if echo "$CHANGED_FILES" | grep -q "terraform/environments/prod/"; then
-            ENVIRONMENTS="$ENVIRONMENTS\"prod\","
+            ENVIRONMENTS='["prod"]'
           fi
 
-          # 공통 모듈이 바뀌면 모든 환경에서 Plan을 수행합니다.
           if echo "$CHANGED_FILES" | grep -q "terraform/modules/"; then
-            ENVIRONMENTS="\"prod\""
+            ENVIRONMENTS='["prod"]'
           fi
 
-          # 마지막 쉼표를 제거하고 JSON 배열 형식으로 변환합니다.
-          ENVIRONMENTS=$(echo "$ENVIRONMENTS" | sed 's/,$//')
-          ENVIRONMENTS="[$ENVIRONMENTS]"
-
           echo "감지된 환경: $ENVIRONMENTS"
-          echo "environments=$ENVIRONMENTS" >> $GITHUB_OUTPUT
+          {
+            echo "environments<<EOF"
+            echo "$ENVIRONMENTS"
+            echo "EOF"
+          } >> "$GITHUB_OUTPUT"
 
   # 환경별 Terraform init/fmt/validate/plan을 수행하고 결과 파일을 아티팩트로 남깁니다.
   terraform-plan-checks:

From 3a547f2ac39d550df42166571513c3b37245cc1b Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 18:39:48 +0900
Subject: [PATCH 7/9] =?UTF-8?q?fix:=20PR=20=ED=8C=8C=EC=9D=B4=ED=94=84?=
 =?UTF-8?q?=EB=9D=BC=EC=9D=B8=20=EC=8A=A4=ED=82=B5=EB=90=98=EB=8A=94=20?=
 =?UTF-8?q?=EC=A7=81=EB=A0=AC=ED=99=94=20=EB=AC=B8=EC=A0=9C=20=EC=88=98?=
 =?UTF-8?q?=EC=A0=95=20(#7)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .github/workflows/terraform-plan.yml | 46 ++++++++++++----------------
 1 file changed, 19 insertions(+), 27 deletions(-)

diff --git a/.github/workflows/terraform-plan.yml b/.github/workflows/terraform-plan.yml
index 49b82c6..5dc6561 100644
--- a/.github/workflows/terraform-plan.yml
+++ b/.github/workflows/terraform-plan.yml
@@ -26,7 +26,7 @@ jobs:
   # 변경된 Terraform 파일을 기준으로 영향받는 환경을 계산
   detect-changes:
     name: 변경 환경 감지
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     outputs:
       environments: ${{ steps.detect.outputs.environments || '[]' }}
     steps:
@@ -45,33 +45,36 @@ jobs:
           echo "변경된 파일 목록:"
           echo "$CHANGED_FILES"
 
-          # prod 환경 또는 공통 모듈 변경 시 prod 환경 Plan을 수행합니다.
-          ENVIRONMENTS='[]'
+          # 변경된 환경 목록을 배열로 수집합니다.
+          ENVIRONMENTS=()
           if echo "$CHANGED_FILES" | grep -q "terraform/environments/prod/"; then
-            ENVIRONMENTS='["prod"]'
+            ENVIRONMENTS+=("prod")
           fi
 
           if echo "$CHANGED_FILES" | grep -q "terraform/modules/"; then
-            ENVIRONMENTS='["prod"]'
+            ENVIRONMENTS+=("prod")
           fi
 
-          echo "감지된 환경: $ENVIRONMENTS"
-          {
-            echo "environments<<EOF"
-            echo "$ENVIRONMENTS"
-            echo "EOF"
-          } >> "$GITHUB_OUTPUT"
+          # 중복을 제거한 뒤 JSON 배열 문자열로 변환합니다.
+          if [ ${#ENVIRONMENTS[@]} -eq 0 ]; then
+            ENVIRONMENTS_JSON='[]'
+          else
+            ENVIRONMENTS_JSON=$(printf '%s\n' "${ENVIRONMENTS[@]}" | sort -u | jq -R . | jq -cs .)
+          fi
+
+          echo "감지된 환경: $ENVIRONMENTS_JSON"
+          echo "environments=$ENVIRONMENTS_JSON" >> "$GITHUB_OUTPUT"
 
   # 환경별 Terraform init/fmt/validate/plan을 수행하고 결과 파일을 아티팩트로 남깁니다.
   terraform-plan-checks:
     name: 체크 - ${{ matrix.environment }}
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     needs: detect-changes
     if: (needs.detect-changes.outputs.environments || '[]') != '[]' # 변경된 환경이 있을 때만 실행합니다.
     strategy:
       fail-fast: false # 한 환경 실패가 다른 환경 확인을 막지 않도록 유지합니다.
       matrix:
-        environment: ${{ fromJson(needs.detect-changes.outputs.environments || '[]') }} # 감지된 환경별로 병렬 실행합니다.
+        environment: ${{ fromJson(needs.detect-changes.outputs.environments || '[]') }}
 
     steps:
       - name: 코드 체크아웃
@@ -117,16 +120,8 @@ jobs:
         if: steps.init.outcome == 'success'
         working-directory: terraform/environments/${{ matrix.environment }}
         run: |
-          case "${{ matrix.environment }}" in
-            prod)
-              TFVARS_CONTENT="${TERRAFORM_TFVARS_PROD}"
-              SECRET_NAME="TERRAFORM_TFVARS_PROD"
-              ;;
-            *)
-              echo "오류: 지원하지 않는 환경입니다: ${{ matrix.environment }}"
-              exit 1
-              ;;
-          esac
+          TFVARS_CONTENT="${TERRAFORM_TFVARS_PROD}"
+          SECRET_NAME="TERRAFORM_TFVARS_PROD"
 
           if [ -z "${TFVARS_CONTENT}" ]; then
             echo "오류: GitHub Secret ${SECRET_NAME}를 설정해야 합니다."
@@ -191,16 +186,13 @@ jobs:
   # 업로드된 결과 파일을 읽어 PR 댓글을 환경별로 갱신
   comment-plan-results:
     name: PR 댓글 갱신
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     needs:
       - detect-changes
       - terraform-plan-checks
     if: always() && (needs.detect-changes.outputs.environments || '[]') != '[]' && github.event_name == 'pull_request'
-
-    # 특정 환경 댓글 실패가 다른 환경 댓글을 막지 않도록 유지
     strategy:
       fail-fast: false
-      # 감지된 환경별로 댓글을 분리
       matrix:
         environment: ${{ fromJson(needs.detect-changes.outputs.environments || '[]') }}
 

From 2d03cdc9a042c118745a62c3e5ae1abaa746020f Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 18:42:33 +0900
Subject: [PATCH 8/9] =?UTF-8?q?fix:=20PR=20=ED=8C=8C=EC=9D=B4=ED=94=84?=
 =?UTF-8?q?=EB=9D=BC=EC=9D=B8=20=EC=8A=A4=ED=82=B5=EB=90=98=EB=8A=94=20?=
 =?UTF-8?q?=EB=AC=B8=EC=A0=9C=EB=A5=BC=20=EC=9C=84=ED=95=9C=20=EB=94=94?=
 =?UTF-8?q?=EB=B2=84=EA=B7=B8=20=EC=9E=A1=20=EC=B6=94=EA=B0=80=20(#7)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .github/workflows/terraform-plan.yml | 30 ++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/.github/workflows/terraform-plan.yml b/.github/workflows/terraform-plan.yml
index 5dc6561..fb061b6 100644
--- a/.github/workflows/terraform-plan.yml
+++ b/.github/workflows/terraform-plan.yml
@@ -65,6 +65,31 @@ jobs:
           echo "감지된 환경: $ENVIRONMENTS_JSON"
           echo "environments=$ENVIRONMENTS_JSON" >> "$GITHUB_OUTPUT"
 
+  # detect-changes 출력값을 바로 확인하기 위한 디버그 잡
+  debug-detect-changes:
+    name: 디버그 - 감지 결과
+    runs-on: ubuntu-22.04
+    needs: detect-changes
+    if: always()
+
+    steps:
+      - name: detect-changes 출력 확인
+        env:
+          ENVIRONMENTS: ${{ needs.detect-changes.outputs.environments }}
+        run: |
+          echo "detect-changes environments 원본: $ENVIRONMENTS"
+          printf 'detect-changes environments quoted: <%s>\n' "$ENVIRONMENTS"
+          echo "detect-changes environments 길이: ${#ENVIRONMENTS}"
+          echo "detect-changes environments 바이트:"
+          printf '%s' "$ENVIRONMENTS" | od -An -tx1
+
+          echo "detect-changes environments JSON 파싱 시도:"
+          if [ -n "$ENVIRONMENTS" ]; then
+            printf '%s\n' "$ENVIRONMENTS" | jq -c .
+          else
+            echo "값이 비어 있습니다."
+          fi
+
   # 환경별 Terraform init/fmt/validate/plan을 수행하고 결과 파일을 아티팩트로 남깁니다.
   terraform-plan-checks:
     name: 체크 - ${{ matrix.environment }}
@@ -80,6 +105,11 @@ jobs:
       - name: 코드 체크아웃
         uses: actions/checkout@v4
 
+      - name: Matrix 디버그
+        run: |
+          echo "matrix.environment=${{ matrix.environment }}"
+          echo "needs.detect-changes.outputs.environments=${{ needs.detect-changes.outputs.environments }}"
+
       # 출력 파일 기반으로 결과를 다루기 위해 wrapper를 비활성화
       - name: Terraform 설치
         uses: hashicorp/setup-terraform@v3

From 90c428ff8576b27eaa44798c52c09ac9b00c44ae Mon Sep 17 00:00:00 2001
From: eedo_y <doup2001@naver.com>
Date: Sat, 4 Apr 2026 18:46:43 +0900
Subject: [PATCH 9/9] =?UTF-8?q?fix:=20PR=20=ED=8C=8C=EC=9D=B4=ED=94=84?=
 =?UTF-8?q?=EB=9D=BC=EC=9D=B8=20=EC=8A=A4=ED=82=B5=EB=90=98=EB=8A=94=20?=
 =?UTF-8?q?=EB=AC=B8=EC=A0=9C=20=EC=88=98=EC=A0=95=20(#7)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .github/workflows/terraform-plan.yml | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/terraform-plan.yml b/.github/workflows/terraform-plan.yml
index fb061b6..9114cf6 100644
--- a/.github/workflows/terraform-plan.yml
+++ b/.github/workflows/terraform-plan.yml
@@ -15,18 +15,16 @@ permissions:
   pull-requests: write
   id-token: write
 
-# 환경변수 설정
-env:
-  GCP_WORKLOAD_IDENTITY_PROVIDER: ${{ secrets.GCP_WORKLOAD_IDENTITY_PROVIDER }}
-  GCP_SERVICE_ACCOUNT: ${{ secrets.GCP_SERVICE_ACCOUNT }}
-  TERRAFORM_STATE_BUCKET: ${{ secrets.TERRAFORM_STATE_BUCKET }}
-  TERRAFORM_TFVARS_PROD: ${{ secrets.TERRAFORM_TFVARS_PROD }}
-
 jobs:
   # 변경된 Terraform 파일을 기준으로 영향받는 환경을 계산
   detect-changes:
     name: 변경 환경 감지
     runs-on: ubuntu-22.04
+    env:
+      GCP_WORKLOAD_IDENTITY_PROVIDER: ""
+      GCP_SERVICE_ACCOUNT: ""
+      TERRAFORM_STATE_BUCKET: ""
+      TERRAFORM_TFVARS_PROD: ""
     outputs:
       environments: ${{ steps.detect.outputs.environments || '[]' }}
     steps:
@@ -71,6 +69,11 @@ jobs:
     runs-on: ubuntu-22.04
     needs: detect-changes
     if: always()
+    env:
+      GCP_WORKLOAD_IDENTITY_PROVIDER: ""
+      GCP_SERVICE_ACCOUNT: ""
+      TERRAFORM_STATE_BUCKET: ""
+      TERRAFORM_TFVARS_PROD: ""
 
     steps:
       - name: detect-changes 출력 확인
@@ -96,6 +99,11 @@ jobs:
     runs-on: ubuntu-22.04
     needs: detect-changes
     if: (needs.detect-changes.outputs.environments || '[]') != '[]' # 변경된 환경이 있을 때만 실행합니다.
+    env:
+      GCP_WORKLOAD_IDENTITY_PROVIDER: ${{ secrets.GCP_WORKLOAD_IDENTITY_PROVIDER }}
+      GCP_SERVICE_ACCOUNT: ${{ secrets.GCP_SERVICE_ACCOUNT }}
+      TERRAFORM_STATE_BUCKET: ${{ secrets.TERRAFORM_STATE_BUCKET }}
+      TERRAFORM_TFVARS_PROD: ${{ secrets.TERRAFORM_TFVARS_PROD }}
     strategy:
       fail-fast: false # 한 환경 실패가 다른 환경 확인을 막지 않도록 유지합니다.
       matrix: