This content has been marked as final. Show 5 replies
from [url http://docs.oracle.com/cd/E11882_01/backup.112/e10643/rcmsynta020.htm] here
Backup-based duplication without a target connection RMAN creates duplicate files from pre-existing RMAN backups and copies. The DUPLICATE command must have been issued with the DATABASE clause. This form requires a connection to an auxiliary instance and a recovery catalog. This mode is useful when the target database is not available or a connection to it is not desirable (as mandated by security policy restrictions or a firewall).
Backup-based duplication without connection to target and recovery catalog RMAN creates duplicate files from RMAN backups and copies that were placed in a designated BACKUP LOCATION.
Edited by: swapnil kambli on May 21, 2013 1:36 AM
From 11g onwards it is not necessary to connect with target database to duplicate the database using existing backup that means you can run RMAN duplicate command without connecting with target and catalog as well. Here is one of sample script for backup based duplication without connecting to target database:-
set newname for database to '/database1/testdb/%b';
duplicate target database to testdb
backup location '/database1/rmanbkp'
'/database1/testdb/redo12.log') SIZE 20M REUSE,
'/database1/testdb/redo22.log') SIZE 20M REUSE;
For more information you can refer below link:-