By default RMAN picks one backup location to do duplicate with clause 'BACKUP LOCATION' .
Many times user don't have much space in single location ,hence, the backup piece distributed
to different location and at same time want to use 'BACKUP LOCATION' feature for duplicate.
How to perform the RMAN duplication using the BACKUP LOCATION clause when the RMAN backuppieces are stored on several mount points or directories?
SolutionAn Enhancement request is already in place: 'Unpublished' Bug 12846424 : RMAN DUPLICATE BACKUP LOCATION TO ACCEPT MULTIPLE DIRECTORY PATH LOCATIONS
Create soft link for the rest location in the location we providing in the clause 'BACKUP LOCATION'.
Please perform the following steps, as shown here.
1. Create the softlink on all of the individual RMAN backuppieces required for the RMAN duplicate, as shown in the example here. You may change the '/tmp/rmanbkup' on a different directory where you want to create those softlinks.
ln –s /u02/oracle/level0_backup_21042018 /tmp/rmanbkup/bkp3
ln –s /u03/backup /tmp/rmanbkup/bkp1
ln –s /u04/backup /tmp/rmanbkup/bkp2
Now use /tmp/rmanbkup/ as your backup location in your restore script.
RMAN> catalog start with '/tmp/rmanbkup';