Split Mirror Offline Backup

Use

This section describes how you can use BRBACKUP to perform a split mirror offline backup with your Oracle database.

In an offline backup the database is shut down to split the mirror disks. Therefore, it is considerably faster than a normal offline backup, in which the database is shut down for the duration of the entire backup.

Prerequisites

You set the following parameters in the initialization profile init<DBSID>.sap:

?      backup_type

0       Split command scenario: backup_type = offline_split

0       SPLITINT scenario: backup_type = offline_mirror

Instead of backup_type, you can enter the BRBACKUP command option -t|-type as shown below in "Activities." The BRBACKUP command option takes priority.

?      Split command scenario: split_cmd and resync_cmd

?      SPLITINT scenario: split_options and split_resync

All copies of control files and online redo log files must be located on disks that can be split, for example, in sapdata directories for control files.

Activities

Split Command Scenario

You start BRBACKUP on the backup host using the following command :

brbackup -t offline_split

For more information, see -t|-type.

BRBACKUP then performs the following steps:

...

       1.      Shuts down the database on the productive host, in order to guarantee the consistency of the database for an offline backup.

       2.      Splits the mirror disks using split_cmd.

       3.      Restarts the database on the production host, so that it is again available for the SAP System.

       4.      Backs up the mirror disks on the backup host.

       5.      If you have set resync_cmd, synchronizes the mirror disks with the originals.

SPLITINT Scenario

You start BRBACKUP on the backup host using the following command :

brbackup -t offline_mirror

For more information, see -t|-type.

BRBACKUP and SPLITINT then perform the following steps:

...

       1.      BRBACKUP calls SPLITINT without stopping the database.

       2.      SPLITINT prepares the split. When complete, SPLITINT sends a message to BRBACKUP.

       3.      When BRBACKUP receives the message, it stops the database.

       4.      SPLITINT executes the split. When complete, SPLITINT sends a message to BRBACKUP.

       5.      When BRBACKUP receives the message, it restarts the database.

       6.      SPLITINT completes the split and sends a success message before returning control to BRBACKUP.

       7.      BRBACKUP starts the actual backup (for example, with BACKINT).

Resynchronization (the next step) occurs after the actual backup (for example, with BACKINT) has finished. It is optional and only needs to be executed if the setting in init<DBSID>.sap is split_resync = yes.

       8.      SPLITINT performs the resynchronization and sends a success message before returning control to BRBACKUP.

       9.      BRBACKUP cleans up and terminates.

For more information, see the documentation BC-BRI SPLITINT Interface for Oracle Databases, which you can find on SAP Service Marketplace at:

service.sap.com/dbaora  ®  Media Library  ® Backup and Recovery

See also:

Split Mirror Backup: Software Configuration