Log Area 

All log volumes in a database instance are known collectively as the log area. The database system writes the redo log entries of transactions in the log segments of the log area. Redo log entries are needed, amongst other things, for restoring a consistent database instance state after a restart or a system breakdown.

The database system writes undo log entries in the data area.

 

The database system overwrites the log area cyclically, since a full log area would cause the database to shut down. You must carry out log backups at regular intervals, because the database system cannot overwrite the segments in the log area until after a successful log backup.

To monitor the filling level of the log area, you can use the Database Manager GUI, for example.

For the security of your data, we recommend that you mirror the log area. If hardware-based mirroring is not possible, you can set the log mode accordingly.

See also:

Database Manager GUI, Displaying Log Area Information

Concepts of the Database System, Logging Transactions and Backing Up Log Entries

Database Administration in CCMS: MaxDB, Monitoring the Log Area

Database Administration in CCMS: SAP liveCache, Monitoring the Log Area