Migrate ECS to Simple Application Server

Notes

• Create snapshots to back up data.

  For more information, see the following topics:

  • ECS instance: Manually create a single snapshot.

  • simple application server: Create a snapshot.

  Warning

  Create snapshots for both the ECS instance and the simple application server. If a migration failure causes data issues, you can use the snapshots to restore the cloud disks.

• Ensure that the runtime environment versions on both servers are identical.

  Some websites have strict requirements for their runtime environment version. If the versions on the source and target servers do not match, the website may not work correctly after migration. Therefore, you must identify the exact version of the runtime environment on your ECS instance. For example, if you have an LNMP environment, identify the versions of Nginx, MySQL, and PHP, and then deploy the same versions on the simple application server.

• Check your network connectivity.

  You must ensure that both the ECS instance and the simple application server have public network access. If you are migrating data across international regions, note that an unstable network can slow down the migration.

Post-migration impacts

Step 1: Install and configure BT-Panel

1. Connect to your Simple Application Server in the console.

   For more information, see Connect to a Linux server.

2. Run the following command to switch to the root user:

   sudo su root

3. Install BT-Panel.

   Go to the BT-Panel website to get an installation package for your operating system. In this example, the Simple Application Server runs CentOS 7.6. Run the following command to install the free edition of BT-Panel.

   Note

   If your Simple Application Server uses the BT-Panel application image, skip this step and configure BT-Panel directly.

   yum install -y wget && wget -O install.sh http://download.bt.cn/install/install_6.0.sh && sh install.sh

   When the installation is complete, the panel access information is displayed. Save the aaPanel Internet Address, aaPanel Internal Address, username, and password. For more information about installing BT-Panel, see BT-Panel Linux installation tutorial.

4. On your local computer, access the aaPanel Internet Address from a browser, and then log in to aaPanel with the username and password.

   After you log in to BT-Panel, you also need to log in to your BT-Panel account. If you do not have a BT-Panel account, you must register one first. Follow the on-screen instructions to complete the process.

5. In BT-Panel, set up a runtime environment that matches the one on the ECS instance.

   1. In the left-side navigation pane, click App Store.

   2. In the App Sort section, click Deployment.

   3. In the list of software, find the following applications and click Install in the Operation column for each.

      • Nginx

        Click Install, select version nginx 1.16, then click Commit.

      • MySQL

        Click Install, select version mysql 5.7, then click Commit.

      • PHP-7.0

        Click Install, keep the default settings, then click Commit.

      • phpMyAdmin

        Click Install, select version phpmyadmin 4.9, then click Commit.

      The installation may take some time.

6. In BT-Panel, add website information.

   1. In the left-side navigation pane, click Website.

   2. On the Website Management page, click Add Site.

   3. In the Add Site dialog box, on the Create Site tab, configure the parameters, then click Commit.

      The following table describes the main parameters. For parameters that are not listed, use the default values.

      Parameter	Description	Example
      Domain name	If you have bound a domain name to the Simple Application Server and completed DNS resolution, enter the domain name. If you have not yet bound a domain name, you can enter the server's public IP address for testing. After the migration is complete, bind and resolve a domain name to the server, and then update this setting.	This example uses the server's public IP address for testing.
      Description	A description of the website. This parameter is optional.	In this example, set this to server-B.
      Root Directory	The root directory of the website. The default root directory in BT-Panel is /www/wwwroot.	In this example, set this to /www/wwwroot/wordpress.

7. In BT-Panel, configure the MySQL database.

   1. In the left-side navigation pane, click Database.

   2. On the Databases page, change the root password.

      1. Click root password.

      2. Enter a custom password in the root password field, then click Commit.

         In this example, the password is set to Test@123.

         Important

         Store your password securely. A leaked password can expose your server to security risks.

   3. On the Databases page, click phpMyAdmin.

   4. On the phpMyAdmin page, enter the username and password for the MySQL root user, then click Run.

   5. In the top menu bar, click SQL. Enter the following commands and click Run.

      To migrate database data, you need a MySQL user with remote connection permissions. Create this user on the MySQL database on the Simple Application Server.

      -- Switch to the mysql database.
      use mysql;
      -- In this example, the username for remote connections is testUser and the password is Test@123.
      create user 'testUser'@'%' IDENTIFIED BY 'Test@123';
      -- Grant remote connection privileges to testUser.
      grant all privileges on *.* to 'testUser'@'%' with grant option;
      -- Apply the privilege changes.
      flush privileges;

   6. In the top menu bar, click SQL. Enter the following commands and click Run.

      To allow the WordPress website to connect to the database after migration, create a database and user on the Simple Application Server with credentials identical to those on the ECS instance.

      In this example, the MySQL database for the WordPress website on the ECS instance is named wordpress, the username is user, and the password is PASSword123..

      -- Create the wordpress database.
      create database wordpress;
      -- Create a new user named user with the password PASSword123.
      create user 'user'@'localhost' identified by 'PASSword123.';
      -- Grant all privileges on the wordpress database to the user.
      grant all privileges on wordpress.* to 'user'@'localhost' identified by 'PASSword123.';
      -- Apply the privilege changes.
      flush privileges;

8. In BT-Panel, configure the firewall.

   1. In the left-side navigation pane, click Security.

   2. In the Firewall section, add a rule to allow traffic on the default MySQL port, 3306.

   3. Click Allow.

Step 2: Configure the ECS instance

Before you use DTS to migrate database data, complete the following configurations on your ECS instance.

1. Configure the security group.

   To migrate data, you must open the required port in the security group of your ECS instance. In this example, both the ECS instance and the Simple Application Server have a MySQL database installed. Therefore, you must open port 3306, the default port for MySQL, in the security group of the ECS instance. For more information, see Add a security group rule.

2. Configure MySQL.

   For data migration, you must create a MySQL user with remote connection permissions on the ECS instance.

   1. Connect to the ECS instance.

      For more information, see Connection methods overview.

   2. Run the following command to log on to the MySQL database.

      mysql -uroot -p

   3. At the Enter password: prompt, enter the password for the MySQL root user.

      Enter the password for your MySQL database.

      Note

      For data security purposes, no output is returned when you enter a password. You need only to enter the correct password and then press the Enter key.

   4. Run the following command to use the wordpress database.

      The wordpress database is the database for the WordPress website.

      use wordpress;

   5. Run the following command to create a database user for remote connection.

      In this example, the username is testUser and the password is Test@123.

      Important

      The password used in this example is for demonstration purposes only. To prevent security risks, set a strong password and keep it confidential.

      create user 'testUser'@'%' IDENTIFIED BY 'Test@123';

   6. Run the following commands in sequence to grant the remote connection permissions to the testUser user.
      1. Grant the remote connection permissions.

         grant all privileges on *.* to 'testUser'@'%' with grant option;

      2. Make the configuration immediately take effect.

         flush privileges;

   7. Run the following command to exit MySQL:

      \q;

Step 3: Copy website files using scp

1. Confirm the simple application server information.

   To remotely copy website files using the scp command, you need the server's public IP address and destination path. First, confirm the following information for the simple application server:

   • Public IP address.

     To find the public IP address, see View server information on the server card.

   • Website root directory.

     In this example, the simple application server's website root directory is /www/wwwroot/wordpress.

2. Connect to the ECS instance.

   For more information, see Connection methods.

3. Run the following command to use scp to migrate the web application from the ECS instance to the simple application server.

   scp -r /usr/share/nginx/html/wordpress/* root@<public IP address of the simple application server>:/www/wwwroot/wordpress

   The parameters in the scp command are described as follows:

   • -r: Recursively copies the entire directory. To copy a single file, remove the-r option.

   • /usr/share/nginx/html/wordpress/*: All files (/*) in the website's source directory on the ECS instance.

   • root@<public IP address of the simple application server>: The username and public IP address of the target simple application server.

   • /www/wwwroot/wordpress: The destination path on the simple application server.

4. When prompted with root@<public IP address of the simple application server>'s password:, enter the password for the simple application server.

   Note

   For data security purposes, no output is returned when you enter a password. You need only to enter the correct password and then press the Enter key.

   The scp command encrypts data during transmission, which can slow the transfer. Wait for the copy to complete.

Step 4: Migrate database data using DTS

1. Log on to 数据传输控制台.

2. In the left-side navigation pane, click Data Migration, and then click Create Task in the upper-left corner.

3. Configure the data migration task.

   The following section describes the key parameters. Use the default settings for other parameters.

   • Task Name: Enter a name for the task. For example, test-swas-01.

   • Source Database (information about the ECS instance):

     Parameter	Configuration example
     Database Type	Select MySQL.
     Access Method	Select Self-managed Database on ECS.
     Instance Region	The region of the ECS instance. For example, China (Hangzhou).
     Replicate Data Across Alibaba Cloud Accounts	In this example, select No.
     ECS Instance ID	Select the ID of your ECS instance.
     Port Number	The default value is 3306.
     Database Account	Enter a database account that has remote connection permissions. For example, testUser.
     Database Password	Test@123 Important The password in this example is for demonstration only. To prevent security risks, use a strong password and keep it confidential.

   • Destination Database (information about the Simple Application Server):

     Parameter	Configuration example
     Database Type	Select MySQL.
     Access Method	Select Public IP Address.
     Instance Region	The region of the Simple Application Server. For example, China (Hangzhou).
     Domain Name or IP	The public IP address of the Simple Application Server.
     Port Number	The default value is 3306.
     Database Account	Enter a database account that has remote connection permissions. For example, testUser.
     Database Password	Test@123 Important The password in this example is for demonstration only. To prevent security risks, use a strong password and keep it confidential.

4. After you configure the parameters, click Test Connectivity and Proceed to verify that DTS can connect to the MySQL databases on both servers.

5. In the CIDR Blocks of DTS Servers dialog box, click Test Connectivity and Proceed.

6. In the Configure Objects and Advanced Settings wizard, configure the required parameters and click Next: Advanced Settings.

   The following list describes the key parameters. For more information, see Data Migration Guide.

   • Task Stages: Select Schema Migration, Full Data Migration, or Incremental Data Migration based on your business requirements.

   • Source Objects: In the Source Objects section, select Select All and click the icon.

   After you complete the configuration, set Conflict resolution for existing tables to Ignore and continue, and set Case sensitivity for target object names to DTS default policy. In the Selected objects section, confirm that the sys and wordpress databases are selected.

7. In the Advanced Configuration wizard, keep the default settings and click Next: Save Task Settings and Precheck.

   Wait for the precheck to complete. If the precheck fails, click View Details next to Failed, resolve the issue based on the error message, and then rerun the precheck.

8. After the precheck passes, click Next: Purchase Instance. A successful precheck means all six checks have passed: source database connectivity, destination database connectivity, source database permissions, destination database permissions, storage engine check, and source database version check.

9. On the Purchase page, select Data Transmission Service (Pay-as-you-go) Service Terms, and then click Buy and Start.

   Data migration is free for this example. However, in practice, charges are based on your usage and the prices displayed on the page. For more information about DTS billing, see billing overview.

   After you start the migration task, wait for it to complete. You can view the status of the task in the migration task list. When the progress of both Schema Migration and Full Data Migration reaches 100% and the task status changes to Completed, the data migration is complete.

Step 5: Verify data migration

1. From your local computer, use a browser to log in to the aaPanel of the simple application server.

2. Check the WordPress website files.

   1. In the left navigation pane of aaPanel, click Site.

   2. On the PHP Project page, click the website's path in the Document Root column.

      In this example, the document root path is /www/wwwroot/wordpress.

      Verify that the WordPress core files, such as wp-config.php, wp-settings.php, and wp-login.php, are present in the /www/wwwroot/wordpress directory. Their presence confirms that the website files migrated successfully.

   3. Check for issues with the website application.

      Verify that the website application on the simple application server is identical to the one on the ECS instance, based on your business requirements. For example, a symbolic link to the wp-config.php file on the ECS instance becomes a regular file after migration, which may have incorrect file permissions. You must then adjust the file permissions for the wp-config.php file on the simple application server.

      To manage files in aaPanel, perform the following steps:

      1. Hover over the file and click Permission.

      2. In the Set permission dialog box, configure the file permissions and click OK.

         Configure the permissions based on your business requirements. This example grants full permissions to the wp-config.php file. Set the owner to root, set the permission to 777 by selecting the read, write, and execute checkboxes for the owner, group, and public, and then select Apply to subdirectory.

3. From your local computer, access http://<public IP address of the simple application server> in a browser to test the WordPress website.

   • If the WordPress website loads correctly and displays the same data as before the migration, the migration is successful. Displaying the default Hello world! post confirms a successful data migration.

   • If the WordPress website fails to load and displays a "Warning: require_once(/www/wwwroot/wordpress/wp-config.php): failed to open stream: Permission denied in /www/wwwroot/wordpress/wp-load.php on line 37" error, you must set the appropriate permissions for the specified file. For instructions, see Check for issues with the website application.

     Warning: require_once(/www/wwwroot/wordpress/wp-config.php): failed to open stream: Permission denied in /www/wwwroot/wordpress/wp-load.php on line 37
     Fatal error: require_once(): Failed opening required '/www/wwwroot/wordpress/wp-config.php' (include_path='.:/www/server/php/70/lib/php') in /www/wwwroot/wordpress/wp-load.php on line 37