Entering content frameFunction documentation Standby Database: BRARCHIVE Backup of Offline Redo Log Files Locate the document in its SAP Library structure

Use

You can use BRARCHIVE with the Oracle Standby Database to back up the offline redo log files.

BRARCHIVE can back up offline redo log files from the primary to the standby instance. This is possible because BRARCHIVE is able to copy offline redo log files to a local or remote hard disk.

Features

The following graphic illustrates how BRARCHIVE works with the standby database:

This graphic is explained in the accompanying text

This process copies the offline redo log files to an NFS-mounted or remote directory, which represents the archive directory (usually saparch) on the standby host. For a mounted directory, the copy process uses an insecure network protocol. In this case, you should use BRARCHIVE with the -w|-verify option.

Starting with SAP Release 4.5A, BRARCHIVE can use reliable copy programs such as rcp or ftp for the copying of the offline redo log files from the primary host onto the standby host, with the backup_dev_type parameter set to stage. Therefore, NFS-mounting and verification are no longer necessary.

This process waits for the offline redo log files to be copied into the local archive directory. If a redo log file was copied completely, BRARCHIVE applies these redo entries to the standby instance with the -m|- modify option, backing up the redo log file and deleting it if necessary. Therefore, BRARCHIVE starts the recovery process of the standby database, in which the offline redo log files are processed individually.

You can delay importing the redo entries, using the <delay> parameter with the -m|- modify option. If a logical error occurs in the primary instance (for example, accidental deletion of a table), you can prevent this error from being imported in the standby instance, by stopping the BRARCHIVE run.

You import the offline redo log files with the following Oracle command:

RECOVER STANDBY DATABASE;

Starting with BRARCHIVE Release 4.5B, when the volume of offline redo log files is high, the import to the standby database is performed in parallel to the backup, leading to significantly faster processing. For more information, see -m|-modify.

Caution

To import the redo log files, the database user (usually SYSTEM) must have SYSDBA authorization.

Caution

When redo entries are imported in which a structural change of the primary database is recorded, the BRARCHIVE process terminates with the following Oracle errors:

ORA-01670: new datafile <file_id> needed for standby database recovery

ORA-01157: cannot identify data file <file_id> - file not found

ORA-01110: data file <file_id>: ‘<file_name>‘

You now need to manually incorporate the structural change in the standby database. To do this, you can use the command:

ALTER DATABASE CREATE DATAFILE ‘<file_name>‘;

You can now restart BRARCHIVE.

For more information, see SAP Note 216108.

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