Specify an Oracle Inventory directory
The first time you install Oracle software on a system, you are prompted to provide an oraInventory directory path.
When you provide an Oracle base path when prompted during installation, or you have set the environment variable ORACLE_BASE for the user performing the Oracle Grid Infrastructure installation, OUI creates the Oracle Inventory directory in the path ORACLE_BASE/../oraInventory. For example, if ORACLE_BASE is set to /opt/oracle/11, then the Oracle Inventory directory is defaulted to the path /opt/oracle/oraInventory, so that the central inventory for all installations is outside of the Oracle base for this particular Oracle installation user.
If you neither enter a path nor set ORACLE_BASE, then the Oracle Inventory directory is placed in the home directory of the user that is performing the installation. For example:
/home/oracle/oraInventory
As this placement can cause permission errors during subsequent installations with multiple Oracle software owners, Oracle recommends that you do not accept this option, and instead use an OFA-compliant path.
For new installations, Oracle recommends that you either create an Oracle path in compliance with OFA structure, such as /u01/app/oraInventory, that is owned by an Oracle software owner, or you set the Oracle base environment variable to an OFA-compliant value.
If you set an Oracle base variable to a path such as /u01/app/grid or /u01/app/oracle, then the Oracle Inventory is defaulted to the path u01/app/oraInventory using correct permissions to allow all Oracle installation owners to write to this central inventory directory.
By default, the Oracle Inventory directory is not installed under the Oracle base directory for the installation owner. This is because all Oracle software installations share a common Oracle Inventory, so there is only one Oracle Inventory for all users, whereas there is a separate Oracle base for each user.