Introduction
A very common challenge encountered when working with active database systems is performing hot backups—that is, creating backups without stopping the database service or making it read-only. Simply copying the data files of an active database will often result in a copy of the database that is internally inconsistent, i.e. it will not be usable or it will be missing transactions that occurred during the copy. On the other hand, stopping the database for scheduled backups renders database-dependent portions of your application to become unavailable. Percona XtraBackup is an open source utility that can be used to circumvent this issue, and create consistent full or incremental backups of running MySQL, MariaDB, and Percona Server databases, also known as hot backups.
As opposed to the logical backups that utilities like mysqldump produce, XtraBackup creates physical backups of the database files—it makes a copy of the data files. Then it applies the transaction log (a.k.a. redo log) to the physical backups, to backfill any active transactions that did not finish during the creation of the backups, resulting in consistent backups of a running database. The resulting database backup can then be backed up to a remote location using rsync, a backup system like Bacula, or DigitalOcean backups.
This tutorial will show you how to perform a full hot backup of your MySQL or MariaDB databases using Percona XtraBackup on Ubuntu 14.04. The process of restoring the database from a backup is also covered. The CentOS 7 version of this guide can be found here.
Prerequisites
To follow this tutorial, you must have the following:
- Superuser privileges on an Ubuntu 14.04 system
- A running MySQL or MariaDB database
- Access to the admin user (root) of your database