tencent cloud

This document describes how to smoothly migrate your public network CLB service from the classic network to a VPC.

Note：

This example is only for reference. In actual migration, please carefully assess the impact and develop the migration plan in advance.

Scenario

Resource configuration of the classic network-based business:

• The DNS domain name is resolved to the public network CLB’s VIP in the classic network.
• The public network CLB is bound with two CVMs (CVM 1 and CVM 2) as the backend servers.
• Applications deployed in CVM 1 and CVM 2 can access the backend TencentDB for Redis and TencentDB for MySQL services.

Migration process

Migration directions

1. Create a VPC as instructed in Creating VPCs.
   
2. Migrate TencentDB for MySQL and TencentDB for Redis instances to the VPC.

   Note：

   During the migration, the TencentDB instances is still connected. Both the original classic network IP and VPC IP addresses remain valid for a certain period after the migration, thus maintaining your service availability. Please complete the migration of other resources within the period.

3. Create images for the classic network-based CVM 1 and CVM 2 as instructed in Creating Custom Images and use the images to create two CVM instances in the VPC. Then test whether the CVMs can access TencentDB instances.

   Note：

   If restarting CVM instances during the migration is acceptable to your business, you can directly switch to VPC during off-peak hours. For detailed directions, see Switching to VPC.

4. Create a public network CLB in the VPC and associate it with the two CVMs created in the previous step. For more information, see Getting Started with CLB. Perform a health check to avoid service interruption due to an exception.
   
5. Resolve the DNS domain name to the public network CLB’s VIP in the VPC.
   
6. Check whether the VPC works well. If yes, release the original public network CLB and CVM resources in the classic network to finish the migration.

   Note：

   The original classic network IP of a TencentDB instance will be automatically released after expiration.