Oracle Message RMAN-06007 - target database not mounted and db_name not set in init.ora

ERRORtarget database not mounted and db_name not set in init.ora
CAUSEThe target database has not mounted the control file, and its init.ora file does not specify the DB_NAME parameter.
ACTIONMOUNT the target database, or add the DB_NAME parameter to its init.ora and restart the instance.