Backing Up Oracle - Computing at Cornell

This example shows backups that are obsolete because there is at least
one backup and they were made no more than 3 days ago:
RMAN> report obsolete redundancy 1 until time 'sysdate-3' device type 'sbt_tape';
RMAN-03022: compiling command: report
Report of obsolete backups and copies
Type Key Completion Time Filename/Handle
-------------------- ------ ------------------ --------------------
Backup Set 1941 21-MAR-01
Backup Piece 1944 21-MAR-01 PARIS/424966318/90/1
Backup Set 1942 21-MAR-01
Backup Piece 1945 21-MAR-01 PARIS/424966318/91/1
Backup Set 1943 21-MAR-01
Backup Piece 1946 21-MAR-01 PARIS/424966374/92/1
The next example shows orphaned backups that are unusable because
they belong to incarnations of the database that are not direct ancestors of
the current incarnation:
RMAN> report obsolete orphan device type 'sbt_tape';
RMAN-03022: compiling command: report
Report of obsolete backups and copies
Type Key Completion Time Filename/Handle
-------------------- ------ ------------------ --------------------
Backup Set 2194 26-MAR-01
Backup Piece 2197 26-MAR-01 OSLO/425411996/16/1
Backup Set 2211 27-MAR-01
Backup Piece 2214 27-MAR-01 OSLO/425461354/19/1
Backup Set 2212 27-MAR-01
Backup Piece 2215 27-MAR-01 OSLO/425461478/21/1
Backup Set 2213 27-MAR-01
Backup Piece 2216 27-MAR-01 OSLO/425461354/20/1
Chapter 7. Day-to-day monitoring of Oracle backups on UNIX 95