Supporting the Raw Device Configuration with BRBACKUP and BRRESTORE

The BRARCHIVE utility remains unchanged in a raw device configuration because offline redo log files must always reside in a file system.

There are some changes in the BRBACKUP and BRRESTORE programs in a raw device configuration, but these changes have no effect on the function scope of the programs. The known functionality of BRBACKUP and BRRESTORE for backing up and restoring file systems remains unchanged.

Use the dd command to access raw devices.

• With
dd, you can write directly from/to the raw device to/from tape (backup/restore to/from tape)

• With
dd, you can copy directly from/to the raw device to/from disk with file system (backup/restore to/from disk)

• In case of a backup with software compression, output of the command
dd is sent directly to the compress. In case of a restore with decompression, output of uncompress is sent to dd.

• In case of a backup on a remote computer, output of
dd is sent for example directly to remsh (/rsh etc.). In case of a restore from a remote computer, it is sent from remsh (/rsh etc.) to the dd command.

• There are new
init.sap parameters for defining the options for the dd command: see dd_flags and dd_in_flags.

Since the dd command does not support a dd continuation tape (in this case an I/O error is reported), a method which is similar to the cpio continuation method is not supported. This means that each individual database file residing on the raw devices must completely fit onto one tape. This restriction does not refer to the BRBACKUP continuation tape management, which means that the BRBACKUP utility can request continuation tapes if they should be necessary for backup of the next database files.