Oracle Inventory and ORA_INSTALL Group Requirements

The Oracle Inventory directory is the central inventory of Oracle software installed on your system. You do not need to create the Oracle central inventory or the ORA_INSTALL group as Oracle Universal Installer creates it for you.

Create operating system groups and users for standard or role-allocated system privileges

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

Unset Oracle Software Environment Variables

If you have an existing installation on your system, and use 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.