Managing Redo Log Files with OMF

With OMF, maintenance of the redo log files is simplified. Complete groups can be added with no file specifications provided simply with the following command:

 ALTER DATABASE ADD LOGFILE; 

To take advantage of this feature, you need to have the DB_CREATE_ONLINE_LOG_DEST_n initialization parameter set. To take advantage of duplexing the redo log files, you need not only DB_CREATE_ONLINE_LOG_DEST_1 to be set but also DB_CREATE_ONLINE_LOG_DEST_2 (more if you are going to be placing members on more than two different devices).

If a group is dropped, all the corresponding OMF files are dropped at the operating system level.

Archived redo log files cannot be OMF files. A specific file system location needs to be created specifically for archived log files. These locations are specified by the LOG_ARCHIVE_DEST_n parameter.

Now we have information on how redo log files work, how to create more, and how to delete existing ones. We also understand about sizing and configuration. But we still need to find out information on the redo log files in the database. The next section helps you with this task.