Guidelines for Using Oracle ASM Disk Groups for Storage

Plan how you want to configure Oracle ASM disk groups for deployment.

During Oracle Grid Infrastructure installation, you can create one or two Oracle ASM disk groups. After the Oracle Grid Infrastructure installation, you can create additional disk groups using Oracle Automatic Storage Management Configuration Assistant (ASMCA), SQL*Plus, or Automatic Storage Management Command-Line Utility (ASMCMD).

Choose to create a second disk group during Oracle Grid Infrastructure installation. The first disk group stores the Oracle Cluster Registry (OCR), voting files, and the Oracle ASM password file. The second disk group stores the Grid Infrastructure Management Repository (GIMR) data files and Oracle Cluster Registry (OCR) backup files. Oracle strongly recommends that you store the OCR backup files in a different disk group from the disk group where you store OCR files. In addition, having a second disk group for GIMR is advisable for performance, availability, sizing, and manageability of storage.

Note:

You must specify the Grid Infrastructure Management Repository (GIMR) location at the time of installing Oracle Grid Infrastructure. You cannot migrate the GIMR from one disk group to another later.
For Oracle Domain Services Clusters, you must configure two separate Oracle ASM disk groups, one for OCR and voting files and the other for the GIMR.

If you install Oracle Database or Oracle RAC after you install Oracle Grid Infrastructure, then you can either use the same disk group for database files, OCR, and voting files, or you can use different disk groups. If you create multiple disk groups before installing Oracle RAC or before creating a database, then you can do one of the following:

Place the data files in the same disk group as the Oracle Clusterware files.
Use the same Oracle ASM disk group for data files and recovery files.
Use different disk groups for each file type.

If you create only one disk group for storage, then the OCR and voting files, database files, and recovery files are contained in the one disk group. If you create multiple disk groups for storage, then you can place files in different disk groups.

With Oracle Database 11g Release 2 (11.2) and later releases, Oracle Database Configuration Assistant (DBCA) does not have the functionality to create disk groups for Oracle ASM.