Wednesday, March 26, 2008

Data Guard Standby with OMF or ASM

OMF

1. Enable forced logging on the primary database.

2. Enable archiving on the primary database.

3. Set all necessary initialization parameters on the primary database.

4. Create an initialization parameter file for the standby database.

5. If the primary database is configured to use OMF, then Oracle recommends that the standby database be configured to use OMF, too. To do this, set the DB_CREATE_FILE_DEST and DB_CREATE_ONLINE_LOG_DEST_n initialization parameters to appropriate values. Maintenance and future role transitions are simplified if the same disk group names are used for both the primary and standby databases.

6. Set the STANDBY_FILE_MANAGEMENT initialization parameter to AUTO.

7. Configure Oracle Net, as required, to allow connections to the standby database.

8. Create a remote login password file for the standby database. Use the same
password for the SYS account as on the primary database.

9. Start the standby database instance without mounting the control file.

ASM


1. If the standby database is going to use ASM, create an ASM instance if one does
not already exist on the standby database system.

2. Use the RMAN BACKUP command to create a backup set that contains a copy of
the primary database’s data files, archived log files, and a standby control file.

3. Use the RMAN DUPLICATE … FOR STANDBY command to copy the data files,
archived redo log files and standby control file in the backup set to the standby
database’s storage area.

The DUPLICATE … FOR STANDBY command performs the actual data movement
at the standby instance. If the backup set is on tape, the media manager must be
configured so that the standby instance can read the backup set. If the backup set
is on disk, the backup pieces must be readable by the standby instance, either by
making their primary path names available through NFS, or by copying them to
the standby system and using RMAN CATALOG BACKUPPIECE command to
catalog the backup pieces before restoring them.