操作系统：64位Linux RedHat 6.3安装Oracle 12C之环境准备工作
1、安装依赖包
binutils-2.20.51.0.2-5.11.el6 (x86_64)
compat-libcap1-1.10-1 (x86_64)
compat-libstdc++-33-3.2.3-69.el6 (x86_64)
compat-libstdc++-33-3.2.3-69.el6 (i686)
gcc-4.4.4-13.el6 (x86_64)
gcc-c++-4.4.4-13.el6 (x86_64)
glibc-2.12-1.7.el6 (i686)
glibc-2.12-1.7.el6 (x86_64)
glibc-devel-2.12-1.7.el6 (x86_64)
glibc-devel-2.12-1.7.el6 (i686)
ksh
libgcc-4.4.4-13.el6 (i686)
libgcc-4.4.4-13.el6 (x86_64)
libstdc++-4.4.4-13.el6 (x86_64)
libstdc++-4.4.4-13.el6 (i686)
libstdc++-devel-4.4.4-13.el6 (x86_64)
libstdc++-devel-4.4.4-13.el6 (i686)
libaio-0.3.107-10.el6 (x86_64)
libaio-0.3.107-10.el6 (i686)
libaio-devel-0.3.107-10.el6 (x86_64)
libaio-devel-0.3.107-10.el6 (i686)
libXext-1.1 (x86_64)
libXext-1.1 (i686)
libXtst-1.0.99.2 (x86_64)
libXtst-1.0.99.2 (i686)
libX11-1.3 (x86_64)
libX11-1.3 (i686)
libXau-1.0.5 (x86_64)
libXau-1.0.5 (i686)
libxcb-1.5 (x86_64)
libxcb-1.5 (i686)
libXi-1.3 (x86_64)
libXi-1.3 (i686)
make-3.81-19.el6
sysstat-9.0.4-11.el6 (x86_64)
2、创建oracle用户和组
[root@ora12c Server]# groupadd oinstall
[root@ora12c Server]# groupadd dba
[root@ora12c Server]# useradd -g oinstall -G dba oracle
[root@ora12c Server]# passwd oracle
Changing password for user oracle.
New UNIX password:
BAD PASSWORD: it is based on a dictionary word
Retype new UNIX password:
passwd: all authentication tokens updated successfully.
[root@ora12c Server]# mkdir -p /oracle/
[root@ora12c Server]# chown -R oracle:oinstall /oracle/
[root@ora12c Server]# chmod -R 775 /oracle/
4、修改内核参数
在/etc/sysctl.conf文件下加入如下参数
[root@ora12c Server]# vim /etc/sysctl.conf
fs.aio-max-nr = 1048576
fs.file-max = 6815744
kernel.shmall = 2097152
kernel.shmmax = 2536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
net.ipv4.ip_local_port_range = 9000 65500
net.core.rmem_default = 262144
net.core.rmem_max = 4194304
net.core.wmem_default = 262144
net.core.wmem_max = 1048586
/sbin/sysctl -p 使参数生效
[root@ora12c Server]# /sbin/sysctl -p
fs.aio-max-nr = 1048576
fs.file-max = 6815744
kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
net.ipv4.ip_local_port_range = 9000 65500
net.core.rmem_default = 262144
net.core.rmem_max = 4194304
net.core.wmem_default = 262144
net.core.wmem_max = 1048586
net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 2
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 = 68719476736
kernel.shmall = 4294967296
注意：kernel.shmmax一般为物理内存的一半，SGA大小不能超过这个值，否则报错
5、修改用户限制
在/etc/security/limits.conf加入相关配置
[root@ora12c Server]# vim /etc/security/limits.conf
oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 1024
oracle hard nofile 65536
oracle soft stack 10240
oracle hard stack 10240
修改文件/etc/pam.d/login，增加以下内容：
session required pam_limits.so
6、配置环境变量
在 .bash_profile配置如下变量
oracle@ora12c ~]$ vim .bash_profile
export ORACLE_BASE=/oracle/ora12c
export ORACLE_HOME=$ORACLE_BASE/db1
export ORACLE_SID=ora12c
export NLS_LANG=AMERICAN_AMERICA.ZHS16GBK
export NLS_DATE_FORMAT="yyyy-mm-dd HH24:MI:SS";
export PATH=$ORACLE_BASE/bin:$ORACLE_HOME/bin:/bin:/sbin:/usr/ccs/bin:/usr/local/bin:$PATH
umask 022
使配置文件生效
[oracle@ora12c ~]$ source .bash_profile
后面的安装就是使用xmanager进行图形界面安装，根据界面提示一步步来就可以了。
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