| Lesson 9 | Perform tablespace recovery with line command RMAN |
| Objective | Use RMAN to restore tablespace, control file, and archived log files. |
Perform Tablespace Recovery
To restore Tablespace to its present location
Start RMAN and connect to the target database and recovery catalog database. For example, enter:
% RMAN CATALOG RMAN/RMAN@BACKUP
RMAN> CONNECT TARGET RMAN/RMAN@PETS
After allocating the channels, take the tablespace that you want to recover offline and restore the tablespace.
For example, to restore tablespace TEMP to the disk you might issue:
RUN{
SQL 'ALTER TABLESPACE TEMP OFFLINE TEMPORARY';
ALLOCATE CHANNEL C1 TYPE DISK;
RESTORE TABLESPACE TEMP;
}
Once the database is restored, open the database.
To restore the control file to its present location by using a recovery catalog
Start RMAN and connect to the target and recovery catalog databases. For example, enter:
% RMAN CATALOG RMAN/RMAN@BACKUP
RMAN> CONNECT TARGET RMAN/RMAN@PETS
Start the instance without mounting the database:
STARTUP NOMOUNT;
If for some reason you need to restore a control file created before a certain date, issue a SET UNTIL command for that date.
Otherwise, allocate one or more channels, restore the control file, mount, and open the database.
RUN
{
ALLOCATE CHANNEL C1 TYPE DISK;
RESTORE CONTROLFILE;
ALTER DATABASE MOUNT;
}
RMAN automatically replicates the control file to the locations specified by the CONTROL_FILES initialization parameter.
To restore archived log files
Start RMAN and connect to the target database and catalog database. For example, enter:
% RMAN CATALOG RMAN/RMAN@BACKUP
RMAN> CONNECT TARGET RMAN/RMAN@PETS
If the database is open, shut it down, and mount it.
SHUTDOWN IMMEDIATE; STARTUP MOUNT
If desired, specify the new location for the restored archived logs by using
SET ARCHIVELOG DESTINATION
.
Otherwise, allocate the channels and restore the archived redo logs.
For example, this script restores all backed up archivelog files:
RUN
{
SET ARCHIVELOG DESTINATION
TO '/ORACLE/TEMP_RESTORE';
ALLOCATE CHANNEL CH1 TYPE DISK;
RESTORE ARCHIVELOG ALL;
}
To avoid performing media recovery on a tablespace that cannot be opened because the database was shut down abruptly during a tablespace backup, issue the following command.
ALTER DATABASE DATAFILE <datafile name>
END BACKUP;
This will bring the tablespaces out of the hot backup mode. You can now open the database.
If you must perform a media recovery, check if the database is mounted. If not, mount the database and issue the RECOVER command.
RECOVER DATABASE;
Once the database is recovered, open the database.
The next lesson uses the Recovery Manager to recover a failed database.
Perform tablespace- Exercise