Recover a MySQL Table with Zmanda Recovery Manager

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If somebody accidentally drops a critical table in MySQL, the application no longer works. The solution to this problem is to utilize the (open source) Zmanda Recovery Manager.

You are a MySQL database administrator. You take regular backups of your MySQL database. Somebody drops a table critical to the MySQL application (for example, the "accounts" table in a SugarCRM application). The MySQL application no longer works. How can you recover from the situation?

The answer is MySQL binary logs. Binary logs track all updates to the database with minimal impact on database performance. MySQL binary logs have to be enabled on the server. You can use the mysqlbinlog MySQL command to recover from the binary logs.

A more comprehensive solution is to use the Zmanda Recovery Manager for MySQL. The mysql-zrm tool allows users to browse the binary logs and selectively restore the database from incremental backups:

      # mysql-zrm --action parse-binlogs   --source-directory=/var/lib/mysql
      /sugarcrm/20060915101613
      Log filename                 | Log Position | Timestamp         | Event Type |    Event
      /var/lib/mysql/my-bin.000015 | 11013        | 06-09-12 06:20:03 | Xid = 4413 | COMMIT;
      /var/lib/mysql/my-bin.000015 | 11159        | 06-09-12 06:20:03 | Query      | DROP TABLE IF EXISTS `accounts`;

Here we're doing selective recovery for incremental backups without the DROP customer table from the SugarCRM database. Do two selective restore commands to restore from the incremental backup done on Sept 15, 2006, without executing the database event DROP TABLE at log position 11159:

      # mysql-zrm --action restore  --backup-set sugarcrm \
         --source-directory=/var/lib/mysql/ sugarcrm/20060915101613/ \
         --stop-position 11014
      # mysql-zrm --action restore   --backup-set sugarcrm \
         --source-directory=/var/lib/mysql/ sugarcrm/20060915101613/ \
         --start-position 11160

See the Zmanda Recovery Manager for MySQL for more information: http://mysqlbackup.zmanda.com.

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