This post was borne out of our mass migration to Rackspace. Naturally, it gets into some advanced, hairy stuff. However, when fully dialed in, this method can take less than 5 minutes, even for large WordPress or Drupal sites. In order to complete these tasks, you will need privileged shell access to both servers (including mysql access), you will need to have rsync installed and configured, and you will need DNS access to the destination server (server2).
* Note: The following steps contain some powerful commands. Please be careful! And don’t execute any command if, after reading the details, you are still unsure what will happen.
1. Export your MySQL Database using mysqldump. This is the only step that must be done while logged into server1.
1-2. Edit db_backup.sql. This only needs to be done if you plan to create a fully-functional development version of your site. Open db_backup.sql in your editor of choice. Find & Replace all old URLs (http://old_site.com) to the new URLs (http://dev_site.server2.com). Rename the .sql file & save it.
*Remaining steps will be done from server2.
2. Create a DNS entry for the site’s new home.
3. Establish the document root for your site’s new home – i.e. create the new site directory.
user@server2:~$ mkdir /path/to/new_site_dir
4. Use rsync to migrate your site directory. Our example will transfer files from old_site_dir on server1 to new_site_dir on server2.
user@server2:/path/to/new_site_dir$ rsync -avz user@server1:/path/to/old_site_dir/ .
4-2. Check owner/group of new directory. Be sure it is consistent with working sites.
5. Create MySQL database, database user, database password, and privileges.
mysql> create database db_name; mysql> create user db_user; mysql> grant all on db_name.* to 'db_user'@'localhost' identified by 'db_password';
6. Upload the db_backup.sql. This will be imported into your newly created database (from previous step).
user@server2:~$ mysql -u mysql_user -p db_name < db_backup.sql [/code]
7. Update your site’s database settings. For WordPress, update wp-config.php with your info from step 5. For Drupal, update settings.php with your info from step 5.
8. Add the VirtualHost record to your apache2 configuration file.
8-2. Restart Apache once the new VirtualHost record has been added.