This parameter is only relevant for Standby Database and Split Mirror Backup.
This parameter defines the connection string to the primary database instance so that BRBACKUP can log on to the primary database.
primary_db = <conn_str>|LOCAL
Default value: none
Possible values:
<conn_str>: connection string for the connect from the standby or split host to the primary (that is, production) database (for example, TNS alias in TNSNAMES.ORA).
LOCAL: local connection on the same host as the primary database
primary_db = C11_PRIM