Creating Standard Groups, Users for 11.2 GRID installation

Oracle® Grid Infrastructure Installation Guide 11g Release 2 (11.2) for Linux
2 Advanced Installation Oracle Grid Infrastructure for a Cluster Preinstallation Tasks 
2.5.6 Example of Creating Standard Groups, Users, and Paths
Example of Creating Standard Groups, Users, and Paths

The following is an example of how to create the Oracle Inventory group (oinstall), and a single group (dba) as the OSDBA, OSASM and OSDBA for 
Oracle ASM groups. In addition, it shows how to create the Oracle Grid Infrastructure software owner (grid), and one Oracle Database owner 
(oracle) with correct group memberships. This example also shows how to configure an Oracle base path compliant with OFA structure with correct
permissions:

# groupadd -g 1000 oinstall
# groupadd -g 1031 dba
# useradd -u 1100 -g oinstall -G dba grid
# useradd -u 1101 -g oinstall -G dba oracle
# mkdir -p  /u01/app/11.2.0/grid        ( GRID_HOME )
# mkdir -p /u01/app/grid                ( ORACLE_BASE fro GRID HOME ) 
# chown -R grid:oinstall /u01
# mkdir /u01/app/oracle                 ( ORACLE_BASE for RDBMS HOME ) 
# chown oracle:oinstall /u01/app/oracle
# chmod -R 775 /u01/

After running these commands, you have the following groups and users:

    An Oracle central inventory group, or oraInventory group (oinstall). Members who have the central inventory group as their primary group, 
    are granted the OINSTALL permission to write to the oraInventory directory.

    A single system privileges group that is used as the OSASM, OSDBA, OSDBA for ASM, and OSOPER for ASM group (dba), whose members are granted 
    the SYSASM and SYSDBA privilege to administer Oracle Clusterware, Oracle ASM, and Oracle Database, and are granted SYSASM and OSOPER for ASM 
    access to the Oracle ASM storage.

    An Oracle grid installation for a cluster owner (grid), with the oraInventory group as its primary group, and with the OSASM group as the 
    secondary group, with its Oracle base directory /u01/app/grid.

    An Oracle Database owner (oracle) with the oraInventory group as its primary group, and the OSDBA group as its secondary group, with its 
    Oracle base directory /u01/app/oracle.

    /u01/app owned by grid:oinstall with 775 permissions before installation, and by root after the root.sh script is run during installation. 
    This ownership and permissions enables OUI to create the Oracle Inventory directory, in the path /u01/app/oraInventory.

    /u01 owned by grid:oinstall before installation, and by root after the root.sh script is run during installation.

    /u01/app/11.2.0/grid owned by grid:oinstall with 775 permissions. These permissions are required for installation, and are changed during 
    the installation process.

    /u01/app/grid owned by grid:oinstall with 775 permissions before installation, and 755 permissions after installation.

    /u01/app/oracle owned by oracle:oinstall with 775 permissions.