RMAN Backup with an External Backup Library (SAP Library - SAP Database Guide: Oracle (BC-DB-ORA-DBA))

RMAN Backup with an External Backup Library

Use

You can use external backup software together with the Oracle Recovery Manager (RMAN) to back up the database. To back up data to tape, the Oracle System Backup to Tape (SBT) interface is implemented as a dynamic function library. The type of backup media you can use depends on the external backup tool and the corresponding backup library.

Note

Before SAP Web Application Server (SAP Web AS) 6.20, you had to use BACKINT (that is, backup_dev_type = rman_util) when backing up with an external backup library. Starting from SAP Web AS Release 6.20, you do not have to use BACKINT.

RMAN saves the database files, but copies of profiles, logs, and a copy of the control files are made to a local or remote disk. Therefore, there are two new values for backup_dev_type:

backup_dev_type = rman_disk

backup_dev_type = rman_stage

When using a remote disk, you can form a common "staging" area for several systems, which simplifies the further backup of the copied profiles and logs.

Activities

The database is backed up in the following phases:

BRBACKUP or BRARCHIVE calls RMAN and starts the Oracle server process. The Oracle server process reads the data to be backed up from the Oracle database, and transfers it to the external backup library. The external backup library acts as a backup client. The backup client passes the data to the backup server. The server backs up the data to the storage medium.
Normally, BRBACKUP uses the BACKINT interface to pass the control file, the initialization profile and the log files to the backup client. The backup client passes the data to the backup server. The server backs up the data to the storage medium. This control file contains information on the backup of the files from the first phase.
You can also let BRBACKUP copy control file, profile, and log files to local or remote disk instead of calling BACKINT. Therefore, you do not need BACKINT any longer when performing RMAN backups with an external backup library.

For more information, see the values rman_disk or rman_stage for the backup_dev_type parameter.

This feature is available starting with Release 6.20 of SAP Web AS and BRBACKUP 6.10 patch level 6.

Caution

You must back up the copies of the control file, profile, and log files to storage medium on your own. You can normally do this directly with the external backup tool.

This graphic is explained in the accompanying text

You can use the following backup variant for external software, with or without RMAN:

backup_dev_type backup_mode	util_file without RMAN	rman_util with RMAN and external SBT backup library	rman_disk rman_stage with RMAN and external SBT backup library
partial	X	X+BACKINT	X
all	X	X+BACKINT	X
full (level 0)	X+cat.	X+BACKINT	X
incr (level 1)		X+BACKINT	X

Key:

X: Backup possible

X+cat.: Backup and subsequent cataloging possible

X+BACKINT: Backup with subsequent backup of the profile, log and control files with BACKINT possible

As before, you can make normal database backups with the BACKINT interface and external backup tools, using the following entry in the initialization profile init<DBSID>.sap:

backup_dev_type = util_file|util_file_online

For more information, see backup_dev_type and backup_mode.

Subsequent cataloging means that a full backup can be used as a reference backup in an incremental backup strategy.

Since RMAN can back up only database files and not profiles or logs, the profile, log, and control files are backed up in a second phase with BRBACKUP and the BACKINT interface or to local or remote disk.

For more information, see Profile Parameters and BRBACKUP Command Options.