The XBSA Interface

ON–Bar and the storage manager communicate through the X/Open Backup Services Application Programmer's Interface (XBSA), which enables the storage manager to manage media for the database server. By using an open-system interface to the storage manager, ON–Bar can work with a variety of storage managers that also use XBSA.

Each storage manager develops and distributes a unique version of the XBSA shared library. You must use the version of the XBSA shared library provided with the storage manager. For example, if you use ISM, use the XBSA shared library provided with ISM. ON–Bar and the XBSA shared library must be compiled the same (32-bit or 64-bit).

ON–Bar uses XBSA to exchange the following types of information with a storage manager:

• Control data. ON–Bar exchanges control data with a storage manager to verify that ON–Bar and XBSA are compatible, to ensure that objects are restored to the proper instance of the database server and in the proper order, and to track the history of backup objects.
• Backup or restore data. During backups and restores, ON–Bar and the storage manager use XBSA to exchange data from specified storage spaces or logical-log files.

ON–Bar uses XBSA transactions to ensure data consistency. All operations included in a transaction are treated as a unit. All operations within a transaction must succeed for objects transferred to the storage manager to be restorable.