SAPDBA Organizing Disk Storage

SAP recommends storing the files of the database system on different physical disks. The files should be distributed among the disks like in the following example:

Distribution of Directories: Example

Disk no.: Directory	Contents of directory
Disk 1: origlogA	Online redo log files from the first and third group (Set A)
Disk 2: origlogB	Online redo log files from the second and fourth group (Set B)
Disk 3: mirrorlogA	Mirrored online redo log files from the first and third group (Set A)
Disk 4: mirrorlogB	Mirrored online redo log files from the second and fourth group (Set B)
Disk 5: sapdata1	Database files, mirror of the control file
Disk 6: sapdata2	Database files, mirror of the control file
Disk 7: sapdata	Other database files in sapdata3 up to sapdata , each on separate disks when possible

In this example, the control file is mirrored twice. Please make sure that the number and descriptions of the control file and its mirrors agree with the entry in the init.ora profile. The database files can be distributed among any number of disks.

Make sure that the offline redo log files (online redo log files saved to the archive directory) are not kept on one of the disks of the online redo logs. The offline redo log files have not been taken into account in the above example.

A disk assignment like the one described above is essential for reliable database operations. For performance reasons, you should distribute the online redo log groups to four disks.