CentOS Oracle RAC 实验
Oracle RAC（Real Application Clusters）是一种高可用性、可伸缩性和容错性的数据库解决方案，它可以跨物理主机或虚拟服务器集成多个Oracle数据库实例，实现共享存储，实现更高的系统性能和灵活性。
使用CentOS操作系统，可以极大的降低系统的成本，下面我们来详细解释在CentOS系统上安装Oracle RAC的过程，并对每个步骤进行解释。
第一步、CentOS基础环境的安装
在安装Oracle RAC之前，需要先安装CentOS系统，这里给出一个简单例子：
[website@localhost ~]$ sudo yum update
[website@localhost ~]$ sudo yum -y install vim wget net-tools epel-release bash-completion
[website@localhost ~]$ sudo yum -y groupinstall "Development Tools"
第二步、Oracle Pre-Installation Setup
执行预安装检查之前，在Linux 上需要执行以下命令：
[website@localhost ~]$ sudo yum -y install compat-libstdc++-33
[website@localhost ~]$ sudo yum -y install elfutils-libelf-devel
[website@localhost ~]$ sudo yum -y install libaio-devel
[website@localhost ~]$ sudo yum -y install gcc-c++
预安装检查命令如下：
$ cd /home/oracle/database
$ ./runInstaller -checkRequirements -silent
检查结果：
Checking operating system package requirements…
Check complete. The overall result of this check is: Passed
——————————————————————————-
Checking recommended operating system packages…
…
Check complete. The overall result of this check is: Passed
——————————————————————————-
Pre-check for cluster services setup was unsuccessful on all the nodes.
–>Package: libXp-1.0.0-8.1.el6.i686 (ol6_latest)
Requires: libXtst.so.6
=====================
Perform Prerequisite Checks for the Oracle Grid Infrastructure:
The following configuration scripts need to be run as the “root” user.
/home/oracle/gridSetup.sh
Performing root user operation for Oracle 11g
The following environment variables are set as:
TRACING_THRESHOLD=1
LANG=en_US.UTF-8
ORACLE_OWNER=oracle
ORACLE_HOME=/u01/app/oracle/product/11.2.0/grid
Enter the full pathname of the local bin directory: [/usr/local/bin]:
The inventory pointer is located at /etc/oraInst.loc
The inventory is located at /u01/app/oraInventory
The log of the current session can be found at:
/u01/app/oracle/product/11.2.0/grid/cfgtoollogs/opatch/opatch2014-09-02_08-58-27AM_1.log
Do you want to continue? [y|n]
第三步、创建 Grid 用户并赋权
使用root用户在两个节点上创建Grid用户
[root@localhost ~]$ useradd -g oinstall -G dba -d /home/grid grid
[root@localhost ~]$ passwd grid
[root@localhost ~]$ usermod -a -G asmadmin grid
[root@localhost ~]$ usermod -a -G asmdba grid
[root@localhost ~]$ usermod -a -G dba grid
第四步、安装Oracle Clusterware
[oracle@localhost grid]$ ./gridSetup.sh
Cluster Verification Utility（CVU）
[root@localhost ~]# su - grid
[grid@localhost ~]$ ./runcluvfy.sh stage -pre crsinst -n dgnode1,dgnode2 -fixup -verbose
第五步、安装Oracle Database
安装Oracle Database，步骤如下：
[oracle@localhost ~]$ ./runInstaller -silent -showProgress -ignoreSysPrereqs -ignorePrereq -waitForCompletion oracle.install.option=INSTALL_DB_SWONLY UNIX_GROUP_NAME=oinstall INVENTORY_LOCATION=/u01/app/oraInventory ORACLE_HOME=/u01/app/oracle/product/11.2.0/dbhome_1 ORACLE_BASE=/u01/app/oracle oracle.install.db.InstallEdition=EE oracle.install.db.isCustomInstall=false oracle.install.db.DBA_GROUP=dba oracle.install.db.OPER_GROUP=dba SECURITY_UPDATES_VIA_MYORACLESUPPORT=false DECLINE_SECURITY_UPDATES=true
总结
以上就是CentOS Oracle RAC 实验的全部内容，当然，以上的步骤也非常适用于其他提供了Linux支持的数据库解决方案。该试验解决了高可用性等领域的需求，让一些企业能够更好地拥有一个稳定、可靠的系统。感谢您的阅读！
