BACKUP DATABASE PLUS ARCHIVELOG DELETE INPUT;
In Data Guard environment this command tries to
1.backup archivelog before starting backup
2.delete archivelog before starting backup
4.backup archivelog generated during backup
5.delete archivelog generated during backup which in most cases these logs couldn’t send or applied to standby database.
If you configure archivelog deletion policy as in the following it couldn’t delete archivelog and shows warning as RMAN-08120: warning: archived log not deleted, not yet applied by standby.
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON ALL STANDBY;
How to configure backup with only delete archivelog before starting backup, without trying to delete archivelog during generated backup.