You can back up storage spaces and logical logs only when the database server is in online, quiescent, or fast-recovery mode. However, you can salvage logical logs with the database server offline. The storage-space chunks can be stored on raw disk storage space, in cooked files, or on an NTFS file system (Windows).
Only online storage spaces are backed up. Use the onstat -d utility to determine which storage spaces are online. After you begin the backup, monitor its progress in the ON–Bar activity log and database server message log.