During installation of Oracle Grid Infrastructure, you can specify an optional Oracle Home user associated with the Oracle Grid home.

For example, assume that you use an Administrator user named OraSys to install the software (Oracle Installation user), then you can specify the ORADOMAIN\OraGrid domain user as the Oracle Home user for this installation. The specified Oracle Home domain user must exist before you install the Oracle Grid Infrastructure software.

The Oracle Home user for the Oracle Grid Infrastructure installation can be either the Windows built-in account (LocalSystem) or an existing user. If you specify an existing user as the Oracle Home user, then the Windows User Account you specify must be a domain user or Group Managed Service Account (gMSA) user. When you use an Oracle Home User, a secure wallet in Oracle Cluster Registry (created automatically) stores the Oracle Home User name and password information. If you decide not to create an Oracle Home user, then the Windows built-in account is used as Oracle Home User.

For Oracle Grid Infrastructure 12c release 12.1.0.1, if you choose the Oracle Grid Infrastructure Management Repository option during installation, then use of an Oracle Home user is mandatory. Similarly, if you perform a software-only installation of Oracle Grid Infrastructure, then you must choose a Windows Domain User account to configure the Oracle Grid Infrastructure Management Repository after installation.

During installation, the installer creates the software services and configures the Access Control Lists (ACLs) based on the information you provided about the Oracle Home User.

When you specify an Oracle Home user, the installer configures that user as the Oracle Service user for all software services that run from the Oracle home. The Oracle Service user is the operating system user that the Oracle software services run as, or the user from which the services inherit privileges.