21 Oracle Backup/Restore (2) RMAN - Backup

RMAN – Recovery Manager

• Backup is happen on the data block level. It can save time and space. Would detect the HWM on the file and do not backup data block higher the HWM.
• Compression
• Can detect the bad data block
• Backup Level 0-5. 0 is Full backup.  1-5 can be differential or incremental .

 

RMAN Catalog

-- Create tablepsace to hold repository

CREATE TABLESPACE RMAN

DATAFILE '/u01/app/oracle/oradata/oracledb1/RMAN01.DBF' SIZE 50M REUSE

AUTOEXTEND ON NEXT 64K MAXSIZE 32767M

EXTENT MANAGEMENT LOCAL

SEGMENT SPACE MANAGEMENT AUTO;

-- Create rman schema owner

CREATE USER rman IDENTIFIED BY rman

TEMPORARY TABLESPACE temp 

DEFAULT TABLESPACE rman 

QUOTA UNLIMITED ON rman;

GRANT connect, resource, recovery_catalog_owner TO rman;

rman catalog username/passowrd@SID target username/password@SID

• If SID is not provided, it use the current $ORACLE_SID
• Catalog’s username name and password is the one we create in the above.
• In below screenshot, we only connect to the catalog

In below screenshot,  we connect to the $ORACLE_SID database and catalog and then register database.

Backup database

backup database; 

backup database plus archivelog;

Here is the screenshot of the backup database plus archivelog

Backup tablespace

backup tablespace <TABLESPACE NAME>

backup tablepsace exmple;

Backup data file

backup datafile [datafile path] 

backup datafile '/u01/app/oracle/oradata/oracledb1/example01.dbf';

 

Backup control file

 backup current controlfile;

 

Differential Incremental backup

• Incremental backup would only backup the changed block since the last level 0 incremental backup.
• If there is no level 0 incremental backup. RMAN will first create level 0 and then create the level 1 backup.
• Oracle would not use the FULL backup as base (parent ) for increment backup ( level 1).
• The level 1 backup would only backup the changes since last level 0 or level 1 backup.

 backup incremental level 1 database;

Cumulative Incremental backup

RMAN can also backup Cumulative backup base on the last level 0 backup.

 

BACKUP INCREMENTAL LEVEL 1 CUMULATIVE database

List backup

# Show all backup 

list backup;

# Show/Delete items not needed for recovery

report obsolete;

delete obsolete;