database into a consistent mode that permits the split, as well as to take it out of this mode again.
This configuration enables an offline backup of a very large database in a short time, as well as an online backup that creates very few archive log files, since the backup mode time of the database is kept to a minimum.
A small number of archive logs reduces the space needed for the archive logs in total, as well as speeds up the recovery process of the database. After a restore of an online database, a recovery is needed to return the database to a consistent state. All archive logs that have been created during the backup must be applied. In a split mirror backup, only the archive log files created during the split are applied.
Local mirror - single host
In cases where no dedicated backup server is available, both functions (application and backup) are performed on the same client (or host). Offline backups of mail applications, for instance, could reduce the downtime of the application to minutes instead of hours in this way.
In this type of configuration, only disk image (raw disk) and filesystem backups are supported. Database and application backups, like Oracle and SAP R/3, cannot be supported, since the database has to be mounted on the backup server, which would not be possible on the same server that has the database already mounted.
Remote mirror
Remote mirror technology, such as Continuous Access XP, enhances the configurations shown earlier due to the fact that the backup and application processes utilize different disk array resources at different locations.
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