Cloud Enterprise Network：隔離VPC使用共用服務

您可以使用Terraform搭建本文樣本環境，關於Terraform的安裝和配置，請參考Install Terraform。

下面步驟以Linux主機運行Terraform v1.9.8為例進行介紹，操作前請確保您已經完成Authentication。

第一步：建立資源

1. 為本文的實踐情境建立一個目錄，並進入該目錄。

   mkdir tf-CenSharedVpc && cd tf-CenSharedVpc

2. 建立一個main.tf檔案，用於定義資源資訊。

   touch main.tf

3. 開啟main.tf檔案，複製如下代碼，粘貼到檔案中並儲存。此檔案包含了本文實踐情境中需要用到的資源和對應配置。

   variable "pname" {
     description = "The prefix name for the resources"
     type        = string
     default     = "tf-CenSharedVpc"
   }
   
   variable "default_region" {
     description = "Default region"
     type        = string
     default     = "cn-hangzhou"
   }
   
   variable "az_list" {
     description = "List of availability zones to use"
     type        = list(string)
     default     = ["cn-hangzhou-j", "cn-hangzhou-k"]
   }
   
   variable "vpc_cidr_list" {
     description = "List of VPC CIDR block"
     type        = list(string)
     default     = ["192.168.0.0/16", "172.16.0.0/12", "10.0.0.0/16"]
   }
   
   variable "vsw_cidr_list" {
     description = "List of VSW CIDR block"
     type        = list(string)
     default = [
       "192.168.0.0/24", "192.168.1.0/24",
       "172.16.0.0/24", "172.16.1.0/24",
       "10.0.0.0/24", "10.0.1.0/24"
     ]
   }
   
   variable "ecs_ip_list" {
     description = "List of ECS ip"
     type        = list(string)
     default     = ["192.168.0.124", "172.16.0.222", "10.0.0.112"]
   }
   
   provider "alicloud" {
     region = var.default_region
   }
   
   # --- 3vpc 6vsw 3ecs
   resource "alicloud_vpc" "vpc" {
     count      = length(var.vpc_cidr_list)
     vpc_name   = "${var.pname}-vpc${count.index + 1}"
     cidr_block = var.vpc_cidr_list[count.index]
   }
   
   resource "alicloud_vswitch" "vsw" {
     count        = length(var.vsw_cidr_list)
     vpc_id       = alicloud_vpc.vpc[floor(count.index / length(var.az_list))].id
     cidr_block   = var.vsw_cidr_list[count.index]
     zone_id      = var.az_list[count.index % length(var.az_list)]
     vswitch_name = "${var.pname}-vsw${count.index + 1}"
   }
   
   resource "alicloud_instance" "ecs" {
     count                = length(var.vpc_cidr_list)
     instance_name        = "${var.pname}-ecs${count.index + 1}"
     instance_type        = "ecs.e-c1m1.large"
     security_groups      = [alicloud_security_group.sg[count.index].id]
     vswitch_id           = alicloud_vswitch.vsw[count.index * length(var.az_list)].id
     image_id             = "aliyun_3_x64_20G_qboot_alibase_20230727.vhd"
     system_disk_category = "cloud_essd"
     private_ip           = var.ecs_ip_list[count.index]
     instance_charge_type = "PostPaid"
   }
   
   # --- 3 sg
   resource "alicloud_security_group" "sg" {
     count  = length(var.vpc_cidr_list)
     name   = "${var.pname}-${count.index + 1}"
     vpc_id = alicloud_vpc.vpc[count.index].id
   }
   
   resource "alicloud_security_group_rule" "allow_inbound_ssh" {
     count             = length(var.vpc_cidr_list)
     type              = "ingress"
     ip_protocol       = "tcp"
     nic_type          = "intranet"
     policy            = "accept"
     port_range        = "22/22"
     priority          = 1
     security_group_id = alicloud_security_group.sg[count.index].id
     cidr_ip           = "0.0.0.0/0"
   }
   
   resource "alicloud_security_group_rule" "allow_inbound_icmp" {
     count             = length(var.vpc_cidr_list)
     type              = "ingress"
     ip_protocol       = "icmp"
     nic_type          = "intranet"
     policy            = "accept"
     port_range        = "-1/-1"
     priority          = 1
     security_group_id = alicloud_security_group.sg[count.index].id
     cidr_ip           = "0.0.0.0/0"
   }
   
   # --- cen and tr
   resource "alicloud_cen_instance" "cen" {
     cen_instance_name = "${var.pname}-cen1"
   }
   resource "alicloud_cen_transit_router" "tr" {
     transit_router_name = "${var.pname}-tr"
     cen_id              = alicloud_cen_instance.cen.id
   }
   data "alicloud_cen_transit_router_route_tables" "tr" { # get tr sys table
     transit_router_id               = alicloud_cen_transit_router.tr.transit_router_id
     transit_router_route_table_type = "System"
   }
   
   # 3 attach
   resource "alicloud_cen_transit_router_vpc_attachment" "attach" {
     count             = length(var.vpc_cidr_list)
     cen_id            = alicloud_cen_instance.cen.id
     transit_router_id = alicloud_cen_transit_router.tr.transit_router_id
     vpc_id            = alicloud_vpc.vpc[count.index].id
     zone_mappings {
       zone_id    = var.az_list[0]
       vswitch_id = alicloud_vswitch.vsw[count.index * length(var.az_list)].id
     }
     zone_mappings {
       zone_id    = var.az_list[1]
       vswitch_id = alicloud_vswitch.vsw[count.index * length(var.az_list) + 1].id
     }
     transit_router_vpc_attachment_name = "attach${count.index + 1}"
   }
   
   # 3 propa
   resource "alicloud_cen_transit_router_route_table_propagation" "propa" {
     count                         = length(var.vpc_cidr_list)
     transit_router_route_table_id = data.alicloud_cen_transit_router_route_tables.tr.tables[0].id
     transit_router_attachment_id  = alicloud_cen_transit_router_vpc_attachment.attach[count.index].transit_router_attachment_id
   }
   
   # 1 custom_table
   resource "alicloud_cen_transit_router_route_table" "custom_table" { # create tr custom_table
     transit_router_id               = alicloud_cen_transit_router.tr.transit_router_id
     transit_router_route_table_name = "custom_table"
   }
   
   resource "alicloud_cen_transit_router_route_entry" "tr_entry" {
     transit_router_route_table_id                     = alicloud_cen_transit_router_route_table.custom_table.transit_router_route_table_id
     transit_router_route_entry_destination_cidr_block = "10.0.0.0/16"
     transit_router_route_entry_next_hop_type          = "Attachment"
     transit_router_route_entry_name                   = "entry1_name"
     transit_router_route_entry_description            = "entry1_desc"
     transit_router_route_entry_next_hop_id            = alicloud_cen_transit_router_vpc_attachment.attach[2].transit_router_attachment_id
   }
   
   # associate attach1\2   custom_table
   resource "alicloud_cen_transit_router_route_table_association" "ass1" {
     transit_router_route_table_id = alicloud_cen_transit_router_route_table.custom_table.transit_router_route_table_id
     transit_router_attachment_id  = alicloud_cen_transit_router_vpc_attachment.attach[0].transit_router_attachment_id
   }
   resource "alicloud_cen_transit_router_route_table_association" "ass2" {
     transit_router_route_table_id = alicloud_cen_transit_router_route_table.custom_table.transit_router_route_table_id
     transit_router_attachment_id  = alicloud_cen_transit_router_vpc_attachment.attach[1].transit_router_attachment_id
   }
   # ass attach3 sys_table
   resource "alicloud_cen_transit_router_route_table_association" "ass3" {
     transit_router_route_table_id = data.alicloud_cen_transit_router_route_tables.tr.tables[0].id
     transit_router_attachment_id  = alicloud_cen_transit_router_vpc_attachment.attach[2].transit_router_attachment_id
   }
   
   # vpc entry
   resource "alicloud_route_entry" "vpc_entry" {
     count                 = length(var.vpc_cidr_list)
     route_table_id        = alicloud_vpc.vpc[count.index].route_table_id
     destination_cidrblock = "0.0.0.0/0"
     nexthop_type          = "Attachment"
     nexthop_id            = alicloud_cen_transit_router_vpc_attachment.attach[count.index].transit_router_attachment_id
   }
   
   output "ecs1_login_address" {
     value = "https://ecs-workbench.aliyun.com/?from=EcsConsole&instanceType=ecs&regionId=${var.default_region}&instanceId=${alicloud_instance.ecs[0].id}"
   }
   
   output "ecs2_login_address" {
     value = "https://ecs-workbench.aliyun.com/?from=EcsConsole&instanceType=ecs&regionId=${var.default_region}&instanceId=${alicloud_instance.ecs[1].id}"
   }
   
   output "ecs3_login_address" {
     value = "https://ecs-workbench.aliyun.com/?from=EcsConsole&instanceType=ecs&regionId=${var.default_region}&instanceId=${alicloud_instance.ecs[2].id}"
   }

4. 初始化目錄，完成Terraform的初始化配置。

   terraform init

5. 建立資源。執行後Terraform會先預覽將要建立的資源，確認無誤後，輸入yes正式開始建立。

   terraform apply

第二步：驗證測試

您可以通過以下步驟，測試VPC1、VPC2、VPC3之間的連通性。

1. 登入VPC1下的ECS1執行個體（執行個體名稱為tf-CenSharedVpc-ecs1）。

   您可以在Terraform的Outputs輸出中，找到ECS1的登入地址並複製到瀏覽器開啟，登入時注意認證方式選擇臨時SSH密鑰認證。

   

2. 通過ping命令，ping VPC3下的ECS3執行個體的IP地址，測試VPC1和VPC3之間的連通性。

   ping 10.0.0.112

   經驗證，VPC1和VPC3之間可以正常通訊。

3. 登入VPC2下的ECS2執行個體（執行個體名稱為tf-CenSharedVpc-ecs2），通過ping命令，ping VPC3下的ECS3執行個體的IP地址，測試VPC2和VPC3之間的連通性。

   ping 10.0.0.112

   經驗證，VPC2和VPC3之間可以正常通訊。

4. 登入VPC1下的ECS1執行個體（執行個體名稱為tf-CenSharedVpc-ecs1），通過ping命令，ping VPC2下的ECS2執行個體的IP地址，測試VPC1和VPC2之間的連通性。

   ping 172.16.0.222

   經驗證，VPC1和VPC2之間不能通訊。

第三步：釋放資源

驗證完畢後，如果您不再使用資源，請執行以下命令釋放資源，防止繼續計費。

terraform destroy --auto-approve