Finding the Offline Redo Log Files (SAP Library - SAP Database Guide: Oracle (BC-DB-ORA-DBA))

Finding the Offline Redo Log Files

Use

You find the offline redo log files when using SAPDBA to perform a partial restore and complete recovery of your Oracle database.

SAPDBA attempts to locate valid backups of the offline redo log files by scanning the summary BRARCHIVE log (arch<DBSID>.log). If the backup was performed with an external backup program, SAPDBA attempts to establish a link to that backup program and find the offline redo logs in this way.

Prerequisites

You have restored the backup files. If relevant, you have restored incremental backups.

You have configured and started SAPDBA. Refer to Getting Started with SAPDBA.

Procedure

Choose Restore/recovery ® Partial restore and complete recovery ® Find offline redo logs in SAPDBA.

Choose Find offline redo logs so that SAPDBA can make available the offline redo log files belonging to the lost data files.

To find the backed-up offline redo log files, SAPDBA uses the BRARCHIVE summary log. To find the offline redo logs, SAPDBA searches the directory where Oracle archives the online redo log files.

SAPDBA highlights any gaps in the redo log sequence.

Caution

If the sequence of the redo log files required for recovery is interrupted, you cannot continue with the recovery. A partial recovery with the SAPDBA menu options in Partial restore and complete recovery, but only with loss of data.

Choose Show list of found offline redo logs to display the list of found offline redo logs for the respective instance (that is, the logs beginning with the determined log sequence number) that are required for the recovery process.

SAPDBA displays the following log sequence numbers for each instance (thread):

The fixed number in the BRBACKUP backup used
(if no backup was restored, a value is determined from V$RECOVER_FILE and V$RECOVERY_LOG)

The number of the first offline redo log required (compare Oracle V$RECOVERY_LOG)

The number of the last (online) redo log required

The number SAPDBA suggests

These numbers normally match.

Caution

Only change the log sequence number proposed by SAPDBA in exceptional cases. Only experienced database administrators should attempt this.

If necessary, choose Select instance and change current first required log to change the log sequence number of the first offline redo log file for the restore.

Note

You must get offline redo log files of other instances that were not found from the archiving directories and store them manually or with BRARCHIVE in the local archiving directory. SAPDBA does not perform this action automatically.

Choose Return to continue with the recovery process.

Result

SAPDBA sets the Status of Find offline redo logs to finished.

To continue with the partial restore and complete recovery, perform Restoring the Offline Redo Log Files.