Creating Required Operating System Groups and Users
Depending on whether this is the first time Oracle software is being installed on thissystem and on the products that you are installing,
you may need to create several operating system groups and users.
The following operating system groups and user are required if you are installing Oracle Database:
■ The OSDBA group (dba)
You must create this group the first time you install Oracle Database software on the system.
It identifies operating system user accounts that have database administrative privileges (the SYSDBA privilege).
The default name for this group is dba.
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If you want to specify a group name other than the default dba group, ---(Not Recommended)
then you must choose the Custom installation type to install the software or start Oracle Universal Installer as a user that is not a member of this group.
In this case, Oracle Universal Installer prompts you to specify the name of this group.
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■ The OSOPER group (oper)
This is an optional group.
Create this group if you want a separate group of operating system users to have a limited set of database administrative privileges(the SYSOPER privilege).
By default, members of the OSDBA group also have the SYSOPER privilege.
If you want to specify a separate OSOPER group, other than the default dba group,
then you must choose the Custom installation type to install the software or start Oracle Universal Installer as a user that is not a member of the dba group.
In this case, Oracle Universal Installer prompts you to specify the name of this group.
The usual name chosen for this group is oper.
■ An unprivileged user
Verify that the unprivileged user nobody exists on the system.
The nobody user must own the external jobs (extjob) executable after the installation.
The following operating system group and user are required for all installations:
■ The Oracle Inventory group (oinstall)
You must create this group the first time you install Oracle software on the system.
The usual name chosen for this group is oinstall.
This group owns the Oracle inventory, which is a catalog of all Oracle software installed on the system.
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Note:
If Oracle software is already installed on the system,
then the existing Oracle Inventory group must be the primary group of the operating system user that you use to install new Oracle software.
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■ The Oracle software owner user (typically, oracle)
You must create this user the first time you install Oracle software on the system.
This user owns all of the software installed during the installation.
This user must have the Oracle Inventory group as its primary group.
It must also have the OSDBA and OSOPER groups as secondary groups.
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Note: In Oracle documentation, this user is referred to as the oracle user.
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A single Oracle Inventory group is required for all installations of Oracle software on the system.
After the first installation of Oracle software, you must use the same Oracle Inventory group for all subsequent Oracle software installations on that system.
However, you can choose to create different Oracle software owner users, OSDBA groups, and OSOPER groups (other than oracle, dba, and oper) for separate installations.
By using different groups for different installations, members of these different groups have DBA privileges only on the associated databases rather than on all databases on the system.
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Creating the Oracle Inventory Group
You must create the Oracle Inventory group if it does not already exist.
The following subsections describe how to determine the Oracle Inventory group name, if it exists, and how to create it if necessary.
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Determining Whether the Oracle Inventory Group Exists
When you install Oracle software on the system for the first time, Oracle Universal Installer creates the oraInst.loc file.
This file identifies the name of the Oracle Inventory group and the path of the Oracle Inventory directory.
To determine whether the Oracle Inventory group exists, enter the following command:
# more /etc/oraInst.loc
If the output of this command shows the oinstall group name, then the group already exists.
If the oraInst.loc file exists, then the output from this command is similar to the following:
inventory_loc=/u01/app/oracle/oraInventory
inst_group=oinstall
The inst_group parameter shows the name of the Oracle Inventory group, oinstall.
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Creating the Oracle Inventory Group
If the oraInst.loc file does not exist, then create the Oracle Inventory group by entering the following command:
# /usr/sbin/groupadd oinstall
Creating the OSDBA Group
You must create an OSDBA group in the following circumstances:
■ An OSDBA group does not exist, for example, if this is the first installation of Oracle Database software on the system.
■ An OSDBA group exists, but you want to give a different group of operating system users database administrative privileges in a new Oracle installation.
If the OSDBA group does not exist or if you require a new OSDBA group, then create it as follows.
In the following command, use the group name dba unless a group with that name already exists.
# /usr/sbin/groupadd dba
Creating an OSOPER Group (Optional)
Create an OSOPER group only if you want to identify a group of operating system users
with a limited set of database administrative privileges (SYSOPER operator privileges).
For most installations, it is sufficient to create only the OSDBA group.
If you want to use an OSOPER group, then you must create it in the following circumstances:
■ If an OSOPER group does not exist, for example, if this is the first installation of Oracle Database software on the system
■ If an OSOPER group exists, but you want to give a different group of operating system users database operator privileges in a new Oracle installation.
If you require a new OSOPER group, then create it as follows.
In the following command, use the group name oper unless a group with that name already exists.
# /usr/sbin/groupadd oper
Creating the Oracle Software Owner User
You must create an Oracle software owner user in the following circumstances:
■ If an Oracle software owner user does not exist, for example, if this is the first
installation of Oracle software on the system
■ If an Oracle software owner user exists, but you want to use a different operating
system user, with different group membership, to give database administrative
privileges to those groups in a new Oracle Database installation
Determining Whether an Oracle Software Owner User Exists
To determine whether an Oracle software owner user named oracle exists, enter the
following command:
# id oracle
If the oracle user exists, then the output from this command is similar to the
following:
uid=440(oracle) gid=200(oinstall) groups=201(dba),202(oper)
If the user exists, then determine whether you want to use the existing user or create
another oracle user. If you want to use the existing user, then ensure that the user’s
primary group is the Oracle Inventory group and that it is a member of the
appropriate OSDBA and OSOPER groups.
Creating an Oracle Software Owner User
If the Oracle software owner user does not exist or if you require a new Oracle
software owner user, then create it as follows. In the following procedure, use the user
name oracle unless a user with that name already exists.
1. To create the oracle user, enter a command similar to the following:
# /usr/sbin/useradd -g oinstall -G dba[,oper] oracle
In this command:
■ The -g option specifies the primary group, which must be the Oracle
Inventory group, for example oinstall
■ The -G option specifies the secondary groups, which must include the OSDBA
group and if required, the OSOPER group. For example, dba or dba,oper
2. Set the password of the oracle user:
# passwd oracle
Modifying an Oracle Software Owner User
If the oracle user exists, but its primary group is not oinstall or it is not a member
of the appropriate OSDBA or OSOPER groups, then enter a command similar to the
following to modify it. Specify the primary group using the -g option and any
required secondary group using the -G option:
# /usr/sbin/usermod -g oinstall -G dba[,oper] oracle
Verifying that the User nobody Exists
Before installing the software, perform the following procedure to verify that the
nobody user exists on the system:
1. To determine whether the user exists, enter the following command:
# id nobody
If this command displays information about the nobody user, then you do not
have to create that user.
2. If the nobody user does not exist, then enter the following command to create it:
# /usr/sbin/useradd nobody