Log Area 
The volume storage area needed for redo log management is called the log area. A log area can extend across several log volumes.
The log area is managed by the log writer. The log writer fills the log area with log pages from the log queue.

For security, the log area should always be
mirrored. If possible, you should mirror the log area on a hardware basis.
If hardware-based mirroring is not possible, you can use an appropriate log mode
setting.
In a production database system, make sure that redo log management is always activated, and that the log area cannot be overwritten until it has been backed up (Log Settings).
A full log causes the database to go down. Therefore, you must always carry out log backups in good time. For this purpose, make sure you activate automatic log backup.
In log backups, the log area is not saved as a whole. Instead, it is saved in backup units, called log segments. The size of a log segment is defined by the parameter LOG_SEGMENT_SIZE.