VERITAS Storage Foundation 4.1 for Oracle RAC HP Serviceguard Storage Management Suite Extracts, December 2005

Backing Up and Recovering the Database Using Storage Checkpoints
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 sfrac_ckptcreate command automatically saves control file and log
information when you create a Storage Checkpoint. See “Creating Storage
Checkpoints Using sfrac_ckptcreate” on page 144 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 your intention is to roll back the database to recover from structural changes that
you do not want to maintain, you may want to use the backup control file that was
created by the sfrac_ckptcreate command. The backup control file is located in
the directory
$VXDBA_DBPATH/ $ORACLE_SID / checkpoint_dir/CKPT_NAME .
◆ Make sure that all archived redo logs are available.
A database backup with online and archived logs is required for a complete database
recovery. Query V$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.
Chapter 7, Using Storage Checkpoints and Storage Rollback 139