11g Archive backups

Have you ever heard of archive backups in 11g, if not here it is,

Normally to make sure that database can be brought up from a particular backupset rman will retain all archived redo logs as well which are necessary.

This happens because rman also considers the option that you may want to consider incomplete recovery.

This is not true for archival backups as they are complete in themselves and thus at the end may save you some space as well.

The name is bit confusing, its not just the archival backups it about whole self contained backup which includes your datafiles/controlfiles+archive logs to provide a consistent recovery.

Normally you need the archives to recover once you restore the database, but in this case we don’t need as your backups contained the archives and also they retention is independent of the control_file_record_keep_time and also the retention policy.

RMAN> backup database
format '/u01/app/backup/db_%U.bkp'
tag M1
keep until time 'sysdate+730'
restore point rs1;
Starting backup at 20-MAR-13
using target database control file instead of recovery catalog
current log archived
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=1400 device type=DISK
backup will remain until date 20-FEB-15
archived logs required to recover from this backup will be backed up
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
including current control file in backup set
channel ORA_DISK_1: starting piece 1 at 20-MAR-13
channel ORA_DISK_1: finished piece 1 at 20-MAR-13
piece handle=/u01/app/backup/db_poos2dgof_1_1.bkp tag=M1 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 20-MAR-13

Note: Do not use flash recovery area for archival backups like above, it will fail since this backups has to be retained 2 years, flash recovery area is managed by oracle and the content will be deleted according to the flash retention target.

So the above backup is self contained and no dependency of the archives, you can safely keep them in vault.

Another important aspect to consider is that restore point , if you see above the restore point clause, it will create a restore point in the database with the scn we have backup and its easier to restore with backup now.

Further, the existing backups also can be marked as archival backup with tag and clause keep forever or keep until as like below.

RMAN> change backup tag 'WEEKLY' keep forever;

Hope this helps

-Thanks

Geek DBA