VERITAS Storage Foundation 4.1 Oracle Administrator's Guide

Chapter 8, Using Storage Checkpoints and Storage Rollback
Prerelease 8 September 2005, 8:55am Guidelines for Oracle Recovery
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Guidelines for Oracle Recovery
For optimal Oracle recovery, follow these guidelines:
◆ Back up all control files before Storage Rollback in case the subsequent Oracle recovery is not
successful. Oracle recommends that you keep at least two copies of the control files for each
Oracle database and that you store the copies on different disks. It is also a good idea to back
up the control files before and after making structural changes to databases.
Note The VxDBA utility automatically saves control file and log information when you create a
Storage Checkpoint. See “Creating Storage Checkpoints” on page 349 for more information.
◆ Make sure that the control files are not rolled back.
A control file is a small binary file that describes the structure of the database and must be
available to mount, open, and maintain the database. The control file stores all necessary
database file information, log file information, the name of the database, the timestamp of
database creation, and synchronization information, such as the Storage Checkpoint and
log-sequence information needed for recovery. Rolling back the control file will result in an
inconsistency between the physical database structure and the control file.
Note If you intend to roll back the database to recover from structural changes that you do not
want to maintain, you may want to roll back control files. The VxDBA utility saves control
file and log information and provides the capability to roll back control files. See “Managing
Storage Rollback” on page 358 and “Showing the Backup Control File List” on page 374 for
more information.
◆ Make sure that all archived redo logs are available.
A database backup with online and archived logs is required for a complete database recovery.
Query V$ARCHIVED_LOG to list all the archived log information and V$ARCHIVE_DEST to
list the location of archive destinations.
To restore the necessary archived redo log files, you can query V$LOG_HISTORY to list all
the archived redo log history or query V$RECOVERY_LOG to list only the archived redo logs
needed for recovery. The required archived redo log files can be restored to the destination
specified in the LOG_ARCHIVE_DEST parameter or to an alternate location. If the archived
redo logs were restored to an alternate location, use the ALTER DATABASE RECOVER ...
FROM statement during media recovery.
◆ After Storage Rollback, perform Oracle recovery, applying some or all of the archived redo
logs.