---
title: "Cloud DB for MSSQL VPC Migration"
slug: "cloud-db-for-mssql-vpc-migration"
updated: 2026-09-17T09:25:07Z
published: 2026-09-17T09:25:07Z
canonical: "guide.ncloud-docs.com/cloud-db-for-mssql-vpc-migration"
stale: true
---

> ## Documentation Index
> Fetch the complete documentation index at: https://guide.ncloud-docs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Cloud DB for MSSQL VPC Migration

This section explains how to migrate Cloud DB for MSSQL running in NAVER Cloud Platform's Classic environment to a VPC environment.

The following topics are covered:

- Create Classic Path Service
- Create a backup server
- Database backup
- Configure VPC peering
- Create a Cloud DB for MSSQL for migration
- Database and SID issues troubleshooting

![cdb_mssql_vpcmigration_diagram](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdb_mssql_vpcmigration_digram.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

Follow the steps below in order.

## Create Classic Path Service

Create a Classic Path Service to transfer data between the Classic and VPC environments.

### Create a VPC for Classic Path

First, create a dedicated VPC to configure the Classic Path service.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Networking** > **VPC** > **VPC Management**.
2. Click the **[Create VPC]** button and enter the following information:  

![cdbformssql_classiccdbmigration_3_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_3_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
  - **VPC name**: name of the VPC to be created
  - **IP address range**: **10.36.192.0/19** (CIDR band dedicated to the Classic Path VPC)
  - **Type**: NORMAL
3. After entering the information, click the **[Create]** button.

### Create Classic Path

Create a Classic Path to connect the Classic and VPC environments.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **Networking** > **Classic Path**.
2. Click the **[Create Classic Path]** button and enter the following information:  

![cdbformssql_classiccdbmigration_4_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_4_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
  - **Classic Path name**: name of the Classic Path to be created
  - **VPC**: VPC created above
  - **Note**: memo related to the Classic Path. To edit it, click the **[Edit]** button.
3. After entering the information, click the **[Create]** button.

### Create subnet

Create an additional subnet in the VPC dedicated to the Classic Path you just created.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **VPC > Subnet Management**.
2. Click the **[Create subnet]** button and enter the following information:  

![cdbformssql_classiccdbmigration_5_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_5_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
  - **Subnet name**: name of the subnet.
  - **VPC**: VPC created in Classic Path.
  - **IP address range**: the subnet's IP address range.
  - **Available zone**: available zone in which the subnet is placed.
  - **Network ACL**: network ACL applied to the subnet.
  - **Internet gateway exclusivity**: indicates whether the subnet is connected to the internet. Y is displayed for public subnet, and N is displayed for private subnet.
3. After entering the information, click the **[Create]** button.

## Create a backup server

Create an application server that temporarily stores backup files and is used for restoration operations.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **Server > Server > Create server**.
2. Set the items below in order on the **Set server** tab.  

![cdbformssql_classiccdbmigration_6_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_6_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
  - **VPC**: VPC created in Classic Path.
  - **Subnet**: select a subnet to be used when accessing VPC.
  - **Server created**: number of servers to be created.
  - **Server name**: name of the server to be created.
  - **Public IP**: select **[Assign new public IP]** if remote access is required.
  - **Note**: memo related to the server. To edit it, click the **[Edit]** button.

### Set disk capacity

Adjust the disk size as needed for the backup server.

1. In the **Set storage** page, confirm or modify the following information:  

![cdbformssql_classiccdbmigration_7_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_7_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
  - **Storage name**: name of the storage you want to use
  - **Storage type**: type of storage you want to use
  - **Snapshot name**: automatically set to the name chosen when creating
  - **Size**: 100 GB or more is recommended. This depends on the backup volume.
  - **Storage type**: type of Block Storage to be used
  - **IOPS**: use the default value or set it according to performance needs.

              Note

              

If you need additional disks besides the default ones, you can set them by clicking the **[Add storage]** button.

### Create a backup folder and enable sharing

Create a shared folder on your server for backups and grant **Everyone** permission to store MSSQL backup files in it.

1. Select a folder to use for backups. ![cdbformssql_classiccdbmigration_10-1_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_10-1_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
2. Right-click the folder you created and open the **[backup Properties]** window. ![cdbformssql_classiccdbmigration_10-2_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_10-2_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
3. Select **[Sharing]** from the top tab and click the **[Share…]** button.
4. When the **Choose people to share with** window appears, select **Everyone** from the drop-down menu, and click the **[Add]** button.
5. Change the **Permission Level** for **Everyone** to **Read/Write**.
6. Click the **[Share]** button at the bottom to share.
7. Confirm the **Network Path** to be used for future SQL Server backups.
8. Click the **[Close]** button to finish.

              Note

              

The network path is used as the `TO DISK` path for MSSQL `BACKUP DATABASE` commands.

### Turn off the password protected sharing

Turn off the password protected sharing and public folder sharing settings to allow access to the backup folder. ![cdbformssql_classiccdbmigration_11_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_11_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. From the application server, go to **Control Panel > Network and Internet > Network and Sharing Center > Advanced sharing settings**.
2. Expand the **All Networks** section and configure the following items:
  - **Public folder sharing:** select **Turn off Public folder sharing**.
  - **Password protected sharing**: select **Turn off password protected sharing**.
3. When you have finished setting up the options, click the **[Save changes]** button.

### Check the Classic DB Server information

Check the Cloud DB for MSSQL instance information of the Classic environment to be backed up.

1. In the Classic environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Database** > **Cloud DB for MSSQL** > **DB Server**.  

![cdbformssql_classiccdbmigration_12_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_12_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
2. Select the target instance from the created DB server list.
3. Ensure that it is in the same network band as the migration target.

### Add ACG rules to allow access to Classic DB

If you need direct access to the Classic DB server from the application server, manually add an access-allow rule to the ACG.

1. Click the **[View rules]** button next to the name of the DB server ACG that you checked above.  

![cdbformssql_classiccdbmigration_13_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_13_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
2. In the Set ACG rule window, enter the following items:
  - **Protocol**: TCP
  - **Access source**: **public IP address of the application server**. You can also enter it automatically by clicking the **[myIP]** button.
  - **Allowed port**: 1433
  - **Note**: memo related to the ACG rule. To edit it, click the [Edit] button.
3. Click the **[Add]** button, and then click the **[Apply]** button to save the settings.

              Caution

              

Only set this if the application server needs to connect directly to the Classic DB.

## Database backup

Back up data to a shared folder on the application server for backups created in the existing Classic DB.

### Prepare a Classic Cloud DB for MSSQL database for migration

Create a database to be used in the Classic environment for backup and migration purposes. ![cdbformssql_classiccdbmigration_14_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_14_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. After running SQL Server Management Studio (SSMS), enter the following information to connect to the Classic Cloud DB for MSSQL:
  - **Server type**: database engine
  - **Server name**: DB server information
  - **Authentication**: SQL server authentication
  - **Login**: ID of the DB account
  - **Password**: password of the DB account
2. After connecting, create a test table as shown in the example below.  

![cdbformssql_classiccdbmigration_14-2_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_14-2_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

```
USE cpathdb1
GO

CREATE TABLE tblx (
  idx INT IDENTITY(1,1)
)
GO

INSERT INTO tblx DEFAULT VALUES
GO 2

SELECT * FROM tblx
GO
```

1. Check if the data is displayed correctly on the **Results** tab.

### Add a CLASSICPATH route in the VPC route table

Add a **CLASSICPATH** route entry to communicate with the Classic environment.

1. From NAVER Cloud Platform console, click **VPC > Route Table**. ![cdbformssql_classiccdbmigration_15-1_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_15-1_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
2. Select the desired route table for the public subnet and click the **[Set routes]** button.

![cdbformssql_classiccdbmigration_15-2_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_15-2_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Click the **[Create]** button and enter the following values:
  - **Destination**: 10.0.0.0/8
  - **Target type**: CLASSICPATH
  - **Target name**: name of the Classic Path you set
2. When you are finished, click **[OK]** or **[Apply]** to save the settings.

### Set the ACG for the backup server

Modify the ACG rule to allow the MSSQL server to access the shared folder on the backup server.

1. Check the ACG applied to the application server for backup.
2. Click the **[View rules]** button for the ACG in the console.  

![cdbformssql_classiccdbmigration_16-1_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_16-1_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
3. On the **[Inbound rules]** tab, ensure the following rules are included:
  - Protocol: TCP
  - Access source: 10.0.0.0/8
  - Allowed port: 445
4. If there is no such rule, apply the same item and click the **[OK] > [Apply]** button in order.

### Cloud DB for MSSQL backup

Back up the database in the classic environment to a shared folder on the application server.

1. Connect to SQL Server Management Studio (SSMS).

![cdbformssql_classiccdbmigration_17_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_17_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Enter the queries shown in the example below and execute them sequentially.

```
CREATE TABLE tblx (
    idx INT IDENTITY (1,1)
);
GO

INSERT INTO tblx DEFAULT VALUES;
GO 2

SELECT * FROM tblx;
GO

BACKUP DATABASE cpathdb1
TO DISK = '\\10.36.192.6\backup\cpathdb1.full'
WITH INIT;
GO
```

1. On the **Messages** tab at the bottom, check if the completion time is displayed along with the **"BACKUP DATABASE successfully processed..."** message.

### Check the SID value of the Classic Cloud DB for MSSQL administrator account

Check the SID value of Classic DB to create the same login account in the environment to be restored.

1. Connect to SQL Server Management Studio (SSMS).

![cdbformssql_classiccdbmigration_18_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_18_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Enter and execute the query below.

```
SELECT SID
FROM master.sys.sql_logins
WHERE name = 'testadmin'
```

## Configure VPC peering

Configure peering to enable communication between the Classic Path VPC and the running VPC.

### Check the information of the Classic Path VPC and the running VPC

Check the CIDR bands of the Classic Path VPC and the migration target VPC.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Networking** > **VPC > VPC Management**.

![cdbformssql_classiccdbmigration_19-1_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_19-1_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Check the following items:
  - CIDR of the Classic Path dedicated VPC
  - CIDR of the running VPC
2. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Networking** > **VPC** > **Subnet Management**.

![cdbformssql_classiccdbmigration_19-2_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_19-2_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Check the following items:
  - Subnet of the Classic Path VPC
  - Subnet of the running VPC

              Caution

              

If the CIDR bands overlap, you cannot configure VPC peering.

### Delete the CLASSICPATH route from the route table

Delete the CLASSICPATH route for the VPC peering route operation.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Networking** > **VPC** > **Route Table**.

![cdbformssql_classiccdbmigration_20_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_20_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Select the **route table for the public subnet** where the route to be deleted is set and click the **[Set routes]** button.
2. Find a route entry that meets the following conditions and click the **[Delete]** button:
  - **Destination**: IP address belonging to the Classic Path environment
  - **Target type**: CLASSICPATH
  - **Target name**: name of the Classic Path you created
3. Click the **[Apply]** button to save the changes.

### Configure VPC peering between the Classic Path VPC and the user VPC

VPC peering must be **configured in both directions** for communication between the Classic Path VPC and the user VPC. Each VPC must be in a different CIDR range, and two peerings must be created, with the requester-receiver role reversed for one of them.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Networking** > **VPC** > **VPC Peering**.

![cdbformssql_classiccdbmigration_21_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_21_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Click the **[Create VPC peering]** button and enter the following information:
  - **Requesting VPC**: Classic Path VPC (`vpccpath`)
  - **Accepting VPC**: user VPC (`mssqlvpc`)
  - **Requesting VPC IP address range**: `10.36.192.0/19`
  - **Accepting VPC IP address range**: `10.0.0.0/16`
2. Create one more peering in the opposite direction.
  - **Requesting VPC**: user VPC (`mssqlvpc`)
  - **Accepting VPC**: Classic Path VPC (`vpccpath`)
  - **Requesting VPC IP address range**: `10.0.0.0/16`
  - **Accepting VPC IP address range**: `10.36.192.0/19`
3. Check if both peers have a **status of "Running**."

### Set route table

Once peering is configured successfully, add **a route setting to each VPC that specifies the other VPC as the destination**.

1. **Classic Path VPC → User VPC route setting**
  - Go to **VPC > Route Table**.
  - Select the `vpccpath-default-public-table` item.
  - In the **Routes tab**, check if the following entries exist:  

![cdbformssql_classiccdbmigration_22_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_22_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
    - Destination: `10.0.0.0/16`
    - Target type: `VPCPEERING`
    - Target name: `classicpathvpc2vpc`
  - If the route does not exist, add it manually.
2. **User VPC → Classic Path VPC route setting**
  - Select the route table of the user VPC in the same way (`mssqlvpc-default-public-table`).
  - In the **Routes tab**, check if the following entries exist:  

![cdbformssql_classiccdbmigration_23_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_23_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
    - Destination: `10.36.192.6/32`
    - Target type: `VPCPEERING`
    - Target name: `vpc2classicpathvpc`

## Create a Cloud DB for MSSQL for migration

Create a Cloud DB for MSSQL instance in advance in the VPC environment for backup data migration.

### VPC Cloud DB for MSSQL ACG settings

Check the ACG settings so that the Cloud DB for MSSQL instance in the VPC environment can access the backup server's shared folder.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Database** > **Cloud DB for MSSQL** > **DB Server** > **DB Server 상세 화면 > ACG > [View rules]**.
2. Check if the following ACG rule is included:  

![cdbformssql_classiccdbmigration_25-2_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_25-2_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)
  - Outbound rule
    - **Protocol**: `TCP`
    - **Destination**: `10.36.192.6/32`
    - **Allowed port**: `445`

### Check the VPC Cloud DB for MSSQL server

Check the MSSQL Cloud DB instance in the VPC environment to which you want to migrate your backup files.

1. In the VPC environment of the NAVER Cloud Platform console, navigate to **Menu** > **All Services** > **Database** > **Cloud DB for MSSQL** > **DB Server**.

![cdbformssql_classiccdbmigration_24_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_24_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Select the target DB server and check the following items:
  - **DB service name**: service name of the DB to be restored
  - **DB engine version**: engine version of the DB to be restored
  - **VPC**: name of the VPC to which the DB to be restored is connected
  - **Subnet**: name of the subnet where the DB to be restored is located
  - **Access port**: `1433`
  - **ACG name**: name of the access control group connected to the DB instance

## Database and SID issues troubleshooting

Restore the data backed up to the application server in the Classic Path VPC to the Cloud DB for MSSQL instance in the VPC environment.

### Restore the database using a backup file

Perform the restore by referencing the backup file in the shared folder path of the Classic Path VPC connected through peering.

1. Run SQL Server Management Studio (SSMS) and connect to the MSSQL server in the VPC environment.
2. Run the query below to perform the restore.  

![cdbformssql_classiccdbmigration_26_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_26_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

```
RESTORE DATABASE cpathdb1
FROM DISK = '\\10.36.192.6\backup\cpathdb1.full'
WITH REPLACE;
```

1. Once the restore process is complete, the phrases "**Processed**" and "**RESTORE DATABASE successfully**" will be displayed in the output message.

### SID-based account creation and login verification

Access to the restored database may be restricted if the user account is not created with the same SID as the existing Classic environment. To avoid this issue, create a login account using the **SID value** from the **existing Classic DB**, then check to see if the account has access.

1. Connect to the master database in SQL Server Management Studio (SSMS).
2. Run the syntax below.

![cdbformssql_classiccdbmigration_27_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_27_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

```
CREATE LOGIN AServerAdmin
WITH PASSWORD='P@ssw0rd'
, SID=0x3D75220DEFFB564588417C6A6EBC7BB7
, DEFAULT_DATABASE=[master]
, CHECK_POLICY=OFF
, CHECK_EXPIRATION=OFF
GO
```

1. After executing the command, check if the message **"Command completed"** appears.
2. Then, open the **Connect to server** window in SSMS.

![cdbformssql_classiccdbmigration_28_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_28_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Enter the following items and connect to the server:
  - **Server name**: DB server address of the VPC environment
  - **Authentication**: SQL server authentication
  - **Login**: user account ID
  - **Password**: user password

              Note

              

To ensure proper integrations with database users and normal access, you must assign the same SID as the account used in the Classic environment.

### Grant the VPC Cloud DB for MSSQL console user the DB_OWNER privilege of the restored database

Link an existing console user account to the restored database and grant it the `db_owner` privilege.

![cdbformssql_classiccdbmigration_29_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_29_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. Connect to the restored database in SQL Server Management Studio (SSMS).
2. Run the SQL statement below to create the console user account and assign the `db_owner` role to it.

```
USE cpathdb1
GO

CREATE USER testadmin FOR LOGIN testadmin
GO

ALTER ROLE [db_owner] ADD MEMBER testadmin
GO
```

              Note

              

If the query runs successfully, the console user account `testadmin` will have full privileges on the `cpathdb1` database.

### Check the restored data in the restored database using the Console Admin account

After completing the SID restoration and authorization settings, connect to the database using the console user account to confirm that the restoration was successful.

![cdbformssql_classiccdbmigration_30_ko](https://cdn.document360.io/6998976f-9d95-4df8-b847-d375892b92c2/Images/Documentation/cdbformssql_classiccdbmigration_30_en.png?sv=2026-02-06&spr=https&st=2026-10-27T16%3A42%3A33Z&se=2026-10-27T17%3A42%3A33Z&sr=c&sp=r&sig=MoQtEZXzqQsyJCHxsvSGNoNy6ZXGbnCgGHVOVz0akb4%3D)

1. In SSMS, connect to the `cpathdb1` database with the console user account.
2. Run the following query to verify that the data has been successfully restored:

```
SELECT * FROM tblx
```

              Note

              

If the data is not retrieved, recheck the login SID match or user authorization status. Once the restore and access permissions are complete, the data entered prior to the restore should be displayed normally in the `tblx` table.