The physical group you designate as the Oracle Inventory directory is the central inventory of Oracle software installed on your system. It should be the primary group for all Oracle software installation owners. Users who have the Oracle Inventory group as their primary group are granted the OINSTALL privilege to read and write to the central inventory.

• If you have an existing installation, then OUI detects the existing oraInventory directory from the/etc/oraInst.loc file, and uses this location.

• If you are installing Oracle software for the first time, then you can specify the Oracle inventory directory and the Oracle base directory during the Oracle software installation, and Oracle Universal Installer will set up the software directories for you. Ensure that the directory paths that you specify are in compliance with the Oracle Optimal Flexible Architecture recommendations.

Ensure that the group designated as the OINSTALL group is available as the primary group for all planned Oracle software installation owners.

Create operating system groups and users depending on your security requirements, as described in this install guide.

Set resource limits settings and other requirements for Oracle software installation owners.

Group and user names must use only ASCII characters.

If you have had an existing installation on your system, and you are using the same user account to install this installation, then unset the ORACLE_HOME, ORACLE_BASE, ORACLE_SID, TNS_ADMIN environment variables and any other environment variable set for the Oracle installation user that is connected with Oracle software homes.

Configure the environment of the oracle or grid user by performing the following tasks:

• Set the default file mode creation mask (umask) to 022 in the shell startup file.

• Set the DISPLAY environment variable.