ApsaraDB RDS:One-click migration for public PostgreSQL

Step 1: Configure a NAT Gateway and EIP

In this step, you associate a public IP address with the VPC of the RDS PostgreSQL instance. This allows the RDS PostgreSQL instance to access a self-managed database or a database from another cloud provider that has a public IP address.

1. Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.

2. In the navigation pane on the left, click Database Connection, and then click the link for the VPC that appears next to Network Type.

3. In the VPC console, select the Resource Management tab. In the Public Access Service section, click Create Now.

4. On the NAT Gateway creation page, configure the following key parameters and use the default values for the remaining parameters.

   Parameter	Description	Example
   Elastic IP Address	If you already have an Elastic IP Address, you can select it. For this example, select Purchase Elastic IP Address.	Purchase Elastic IP Address
   Peak Bandwidth	Select a peak bandwidth based on your needs. For this one-click migration, you can set the peak bandwidth to its maximum value to prevent migration slowdowns caused by bandwidth limits.	200 Mbps

5. Click Buy Now.

6. Confirm that the parameter settings are correct, select the terms of service checkbox, and then click Confirm Order.

   After the operation is complete, the NAT Gateway is created, an EIP is associated with it, and an SNAT entry is configured.

7. Click the resource ID of the Elastic IP Address. On the Instance Information page of the EIP, you can view the public IP Address.

Step 2: Configure the source database

Step 3: Run a feasibility assessment

1. Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.

2. In the navigation pane on the left, choose Cloud Migration/DR Deployment. Then, click the Feasibility Assessment tab.

3. In the Configure Scenario and Source Type step of the configuration wizard, select Migration to Cloud for the scenario and Self-managed Instance or Other Instance for the source type. Then, click Next.

4. In the Configure Destination Instance step, click Next.

5. In the Configure Source Instance step, select all options, and then click Next.

6. In the Start Feasibility Assessment step, set the following parameters.

   Parameter	Description
   Migration Task Name	The system automatically generates a name. No modification is required.
   Source VPC/DNS IP	For a self-managed PostgreSQL database on the public network: the public IP address of the database server. For a PostgreSQL instance from another cloud provider: the public endpoint of the instance.
   Port of Source Instance	For a self-managed PostgreSQL database on the public network: the database port. You can run the netstat -a | grep PGSQL command to view the port. For a PostgreSQL instance from another cloud provider: find this information in the management console of the cloud provider.
   Username	The username and password for the migration account created in Step 2.
   Password

7. Click Create Feasibility Assessment Task.

   After the migration assessment is complete, you can view the status of the migration assessment task in the Migration to Cloud list on the Feasibility Assessment page.

   • You can proceed with Migration to Cloud only if the Status is Successful.

   • If the Status is Failed, click View Report in the Actions column and resolve the issue based on the error message. For information about common errors, see Interpret the migration assessment report.

     Note

     Other cloud providers may have custom PostgreSQL plugins. If you encounter a plugin incompatibility error during the migration, submit a ticket.

   After you resolve the errors, you can click Re-assess in the Actions column to run the assessment again.

Step 4: Migrate to the cloud

1. Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.

2. In the navigation pane on the left, choose Cloud Migration/DR Deployment, switch to the Migration to Cloud tab, and then click Create Migration to Cloud Task.

3. In the Create Cloud Migration Task window, select the successful task from Step 3 in the Associated Assessment Task drop-down list.

   After you select an Associated Assessment Task, the other parameters are automatically populated.

4. Click Initiate Migration to Cloud to begin the migration task.

   Warning

   During the migration task, ensure that the source instance is accessible. Do not perform operations such as restarting the instance. If the source instance experiences a transient connection issue or an HA switchover, the migration task fails.

5. Perform the cutover.

   1. In the migration task list, you can click the link in the Cloud Migration Phase column to view the progress of the task.

   2. When the migration phase is Incremental Data Synchronization, click Switchover in the Actions column to promote the RDS PostgreSQL instance to the primary instance and start serving production traffic.

   3. In the Switchover window, follow the on-screen instructions to set the source instance to read-only or stop writes from your applications.

      To set the source instance to read-only:

      -- Set the database to read-only.
      ALTER SYSTEM SET default_transaction_read_only=on;
      -- Reload the parameter configuration to apply the change.
      SELECT pg_reload_conf();
      -- Terminate all existing sessions.
      SELECT pg_terminate_backend(pid) FROM pg_stat_activity 
      WHERE usename not in ('replicator', 'monitor', 'pgsql', 'aurora') AND pid != pg_backend_pid();

   4. Select all checkboxes and click Switch Now. Then, wait for the migration to complete.