Backing up "live" data can cause erroneous or partially updated files after such data is restored from a backup. This is particularly problematic with databases, which typically have relational data that must be kept in sync.



SBAdmin includes the ability to perform a snap shot, or point in time backup of any live data contained in Logical Volumes. Logical Volumes are software storage devices used exclusively on AIX systems and are quickly becoming a standard installation storage configuration on Linux systems.

Logical volumes are created by the Logical Volume Manager (LVM) package. SBAdmin performs snap shot backups by backing up an offline copy of all data in the logical volumes.

This allows users to continue to access and modify data in the online copy, while the backup includes all data as it was when the backup process started. This ensures the relational data, when restored, is all at the same point in time, no matter how long the backup takes.

SBAdmin uses a Split Mirror Backup process on AIX systems to capture data from an offline copy of a mirrored logical volume. All AIX systems use the Logical Volume Manager (LVM) for storing all data.

Logical volumes may be mirrored, keeping a separate up to date copy of all data as the data is changed. SBAdmin will allow you to configure split mirror backups, which will break off a copy of the live data, and use the offline copy to perform the backup.

This is especially useful for backing up live data such as Oracle, DB2, or MySQL databases. When the backup is complete, SBAdmin returns the mirror and syncs it up with the online copy. LVM also allows for 2 mirrors (3 copies) of a logical, so SBAdmin can break off one copy while data and system availability is still preserved using the remaining mirrored copies.

A backup job configured to use split mirrors, whether a specific file system, raw database, or the entire system, performs all the steps in splitting off copies, backing up, and re-syncing the copies making the process automatic and transparent to the user.

On Linux systems SBAdmin uses the Snapshot Logical Volumes. Most Linux systems now support the Logical Volume Manager (LVM) for storing all types of data, from file systems to raw database data. SBAdmin provides a simple user interface for performing LVM snapshot backups.

Now, when performing any SBAdmin backup of LVM data, a copy of the live changing data is automatically created, allowing the original data to be "frozen in time" at the point of the backup. At the same time, users can continue accessing and updating the changed data while the backup is running.

When this "hot backup" completes, the system is returned to normal operation, and the entire process is completely transparent to the users. The interface gives you several options such as which logical volume to create the snapshot, whether to create them all at once or sequentially and whether to continue or fail if there is a problem.

Since the snapshot backups are performed on any data residing in logical volumes, including raw databases and file system data, any and all data, even on a full system backup, may be captured.