Backup Behavior
When a backup is requested, the Tungsten Replicator performs a number of separate, discrete, operations designed to perform the backup operation.
The backup operation performs the following steps:
- Tungsten Replicator identifies the filename where properties about the backup will be stored. The file is used as the primary interface between the underlying backup script and Tungsten Replicator.
- Tungsten Replicator executes the configured backup/restore script, supplying any configured arguments, and the location of a properties file, which the script updates with the location of the backup file created during the process.
- If the backup completes successfully, the file generated by the backup process is copied into the configured directory, for example
/opt/continuent/backups. - Tungsten Replicator updates the property information with a CRC value for the backup file and the standard metadata for backups, including the tool used to create the backup.
A log is created of the backup process into a file according to the configured backup configuration. For example, when backing up using mysqldump the
log is written to the log directory as mysqldump.log. When using a custom script, the log is written to script.log.
As standard, Tungsten Replicator supports two primary backup types, mysqldump and xtrabackup. A third option is based on the
incremental version of the xtrabackup tool. The use of external backup script enables additional backup tools and methods to be supported.
To create a custom backup script, see "Writing a Custom Backup/Restore Script" for a list of requirements and samples.