# Oracle 云存储卷重新分配演示

## 预期的 Terraform 计划输出

当我们执行 `terraform plan -var ch2_enabled=false -var a1_storage_size_gb=200` 时，预期的输出将是：

```
Terraform will perform the following actions:

  # oci_core_instance.ch2_instance[0] will be destroyed
  - resource "oci_core_instance" "ch2_instance" {
      - availability_domain = "..." -> null
      - compartment_id      = "..." -> null
      - display_name        = "ch2-instance" -> null
      - id                  = "..." -> null
      - shape               = "VM.Standard2.1" -> null
      # ... 其他实例属性
    }

  # oci_core_volume.a1_additional_storage will be created
  + resource "oci_core_volume" "a1_additional_storage" {
      + availability_domain = (known after apply)
      + compartment_id      = "..."
      + display_name        = "a1-additional-storage"
      + id                  = (known after apply)
      + size_in_gbs         = 200
    }

  # oci_core_volume_attachment.a1_volume_attachment will be created
  + resource "oci_core_volume_attachment" "a1_volume_attachment" {
      + attachment_type = "paravirtualized"
      + id              = (known after apply)
      + instance_id     = (known after apply)
      + volume_id       = (known after apply)
    }

Plan: 2 to add, 0 to change, 1 to destroy.
```

## 存储卷重新分配流程

1. **终止 ch2 实例** - 释放其所有关联资源（包括引导卷和数据卷）
2. **创建新的 200GB 数据卷** - 为 A1 实例提供额外存储
3. **附加新卷到 A1 实例** - 将新存储空间挂载到目标实例

## 实际执行步骤

在实际环境中，你需要：

1. 确保 ~/.oci/config 文件中有正确的 [korea] 配置
2. 运行 `terraform init` 下载 OCI provider
3. 运行 `terraform plan -var ch2_enabled=false -var a1_storage_size_gb=200` 查看计划
4. 确认计划无误后运行 `terraform apply -var ch2_enabled=false -var a1_storage_size_gb=200`

## 预期结果

- ch2 实例被完全终止，释放其存储资源
- A1 实例获得新的 200GB 数据卷
- ch3 实例保持不变
- 总体资源得到优化配置

## 验证步骤

完成后，你可以在 Oracle 云控制台中验证：
- ch2 实例不再存在
- A1 实例有新的 200GB 数据卷附加
- 存储卷的成本已从 ch2 转移到 A1