Oracle Installation parameter configuration on Linux

First, set a user group for the normal installation of oracle;

[Root @ localhost ~] # Groupadd oinstall
[Root @ localhost ~] # Groupadd DBA

A user account is called Oracle, and a group is called oinstall and DBA.

[Root @ localhost ~] # Useradd-G oinstall-g dba Oracle
[Root @ localhost ~] # Passwd Oracle

This is a pop-up from the system that requires you to perform password verification based on UNIX password management.
Enter the password twice:

Changing password for user oracle.
New UNIX password:
Bad password: it does not contain enough different characters
Retype new Unix Password:
Passwd: All authentication tokens updated successfully.

Modify the Linux Kernel Parameter file:
Linux allows you to modify most Kernel Parameters during system startup and runtime.
The following Kernel Parameter settings are required for Oracle Database 10 GB. The minimum value is given, so if your system uses a large value, do not change it.

VI/etc/sysctl. conf

kernel. shmall = 2097152
kernel. sh mMax = 2147483648
kernel. shmmni = 4096
kernel. SEM = 250 32000 100 128
FS. file-max = 65536
net. ipv4.ip _ local_port_range = 9000 65000
net. core. rmem_default = 4194304
net. core. rmem_max = 4194304
net. core. wmem_default = 262144
net. core. wmem_max = 262144
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kernel. shmall is the physical memory divided by pagesize;
kernel. shmmax is half of the physical memory.
FS. file-Max is 512 multiplied by processes (for example, 128 processes);
net. ipv4.ip _ local_port_range/net. core. rmem_default/net. core. the three parameter settings of rmem_max are different from those in the official documentation. They are modified according to the latest requirements of Metalink 343431.1.
net. ipv4.tcp _ rmem/net. ipv4.tcp _ WMEM parameters generally do not need to be set unless they are in the case of many network transmissions such as dataguard/streams;
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use the command: sysctl-P to view the Left and Right parameter settings

[Root @ localhost ~] # Sysctl-P
Net. ipv4.ip _ forward = 0
Net. ipv4.conf. Default. rp_filter = 1
Net. ipv4.conf. Default. accept_source_route = 0
Kernel. sysrq = 0
Kernel. core_uses_pid = 1
Net. ipv4.tcp _ syncookies = 1
Kernel. msgmnb = 65536
Kernel. msgmax = 65536
Kernel. shmmax = 4294967295
Kernel. Shmall = 268435456
Kernel. shmmax = 2147483648
Kernel. shmmni = 4096
Kernel. SEM = 250 32000 100 128
FS. File-max = 65536
Net. ipv4.ip _ local_port_range = 1024 65000
Net. Core. rmem_default = 4194304
Net. Core. rmem_max = 4194304
Net. Core. wmem_default = 262144
Net. Core. wmem_max = 262144

We recommend that you set a limit on the number of processes that can be used and the number of opened files for each Linux Account.
VI/etc/security/limits. conf
Oracle soft nproc 2047
Hard nproc 16384
Oracle soft nofile 1024
Oracle hard nofile 65536

VI/etc/PAM. d/login
Session required/lib/security/pam_limits.so
Session required pam_limits.so

VI/etc/profile
If [$ user = "oracle"]; then
If [$ shell = "/bin/KSh"]; then
Ulimit-P 16384
Ulimit-N 65536
Else
Ulimit-u 16384-N 65536
Fi
Umask 022
Fi

Create an Oracle installation directory, including Data File Installation
Mkdir-P/U1/APP/Oracle/product/1002/DB
Mkdir-P/U2/oradata

Authorization for installation directory files:
In this way, users with non-root permissions also have read permissions.
Chown-r ORACLE: oinstall/U1/APP/Oracle/U1/APP/Oracle/product/1002/DB/U2/oradata
Chmod-r 777/U1/APP/Oracle/U1/APP/Oracle/product/1002/DB/U2/oradata

If you have installed Multiple Oracle products or databases on the same server, the ORACLE_HOME, oracle_sid, and path variables may be changed. The oracle_base variable should not be changed and can be set in your login configuration file as needed. Oracle provides a utility called oraenv.ProgramTo set other variables.
Log On As Oracle (or log on to the Oracle user directory as a root), and. bash_profile or. profile (bash or KSh) to add oracle_base to the logon configuration file:

Cd/home/Oracle
VI. bash_profile
export oracle_base =/U1/APP/Oracle
export ORACLE_HOME = $ oracle_base/product/1002/DB
export Path = $ path: $ ORACLE_HOME/bin
export oracle_sid = L