it depends alot on what is written on your policy procedure (on retention period and how you are going to do the backup).
maybe you can explain more on what you are backing up (windows image, database or etc).
with more information I might be able to give you more pointers…
Configure Retention Policy is defined to establish how long a backup retain by RMAN before it is expired. If u configure a retention policy & are using FRA, then RMAN & Oracle will take care of automatically remove when it obsolate. The redundancy and the recovery window policies are manually exclusive & either of them may be defined as a time. The procedure is :
1.Launch RMAN & connect to target database (u may connect to recover catalog database if u created one) C:\> RMAN TARGET /
2.To set retention policy to a redundancy of 7,
1.RMAN> configure retention policy to redundancy 7;
3.To view it
1.RMAN> show retention policy;
4.To set retention policy to a recovery window of 7 days,
1.RMAN> configure retention policy to recovery window of 7 days;
5.To clear it,
1.RMAN> configure retention policy clear;
Some more words: If you want to recover ur backup to any point in timeup to 7 days ago (running “archivelog” mode only), then u may set Recovery Window-based Retention Policy of 7 days by:
RMAN> configure retention policy to recovery window of 7 days;
NOTE: This is old RMAN parameter, may be the new parameter set as 3 days