Figure 11 describes the ON–Bar backup sequence. When you issue a backup command, the onbar-driver builds a list of storage spaces and creates a backup session.
In a parallel backup (if BAR_MAX_BACKUP is not set to 1), the onbar-driver starts one or more onbar_d child processes and assigns backup tasks to them. Each onbar_d child process backs up one storage space. Each onbar_d child disappears when the backup of its storage space is done. The onbar-driver keeps creating new children until all the storage spaces are backed up. Then the onbar-driver backs up the logical logs.
If you specify a whole-system backup or set BAR_MAX_BACKUP to 1, the onbar_driver backs up the storage spaces and logical logs serially. No onbar_d child processes are created.
When the backup is complete, the onbar-driver determines whether an error occurred and returns a status in the ON–Bar activity log. After each object is backed up, information about it is added to the emergency boot file on the database server and to the sysutils database.