DB2 command line processor

The DB2® Command Line Processor (CLP) interprets commands for the DB2 database and passes control to a DB2 Server Process.

For Data Protection for SAP for DB2, the LOAD libraryname option instructs DB2 to start the Data Protection for SAP shared library. This process starts the backup or restore operation, dynamically loads the library, and communicates with Data Protection for SAP through the Vendor API.

For starting a backup or restore, the DB2 CLP communicates with the DB2 Server Process and provides information to the Server Process for processing the database.

Figure 1. DB2 backup architecture

This graphic shows the actions that are triggered by a backup database and a restore database command. It shows how the DB2 Server Process and Tivoli Storage Manager interact. This process is described in detail in the following text.

The DB2 BACKUP DATABASE command performs this DB2 Server process:

Creates a unique timestamp to identify the backup.
Loads Data Protection for SAP dynamically as a shared library.
Reads the data from the database containers.
Reads the DB2 configuration files.
Creates data blocks that contain the backup image and passes these blocks to the data mover part of Data Protection for SAP.

The Data Protection for SAP shared library sends the data to the Tivoli® Storage Manager server storage (tape or disk). At the end of the backup process, the DB2 Server process logs the backup in the Recovery History File.

The DB2 RESTORE DATABASE command performs this DB2 Server process:

Loads Data Protection for SAP dynamically as a shared library.
Requests the backup data from the shared library.

The Data Protection for SAP shared library:

Checks with the Tivoli Storage Manager if the backup image is available.
Retrieves the data blocks from Tivoli Storage Manager.
Passes the data blocks to the DB2 Server Process.

The DB2 Server Process

Restores the DB2 data to the database containers.
Logs the restore in the Recovery History File.