How to Install Oracle 11 g on Linux

In order to use Oracle Database, first of all we need to setup Oracle Software. Installation of Oracle Database on Windows is very easy. By running setup.exe from installation CD of Oracle for Windows, we can invoke a setup and by clicking NEXT buttons we can install Oracle Software and Database without any problem. We don’t need any prerequisite actions before installation. But in Linux it’s different. If we want to install Oracle Database on Linux OS, we should follow some prerequisite actions.

Today, we’re going to install Oracle Database on CentOS and mostly used release of Oracle Database – “Oracle Database 11g Release 2”.

Checking minimum hardware requirements 

At least, your system should meet the following requirements:

-           1GB RAM

-           Requirement for swap space in Oracle installation is as follows:

                Available RAM                                      Swap Space Required

                Between 1 GB and 2 GB        1.5 times the size of RAM

                Between 2 GB and 8 GB       Equal to the size of RAM

                More than 8 GB                     .75 times the size of RAM

-           400MB free space in /tmp directory

-           Depending on type of the installation, 1.5-3.5 GB free space for Oracle Software

-           1.5GB free space if new Oracle Database is created

Getting familiar with requirements mentioned above, we need to get hardware information of our system. To check the size of RAM, Swap space and tmp directory, we run these commands:

-           To check the size of physical memory, execute      

                    grep MemTotal     /proc/meminfo

-           To check the size of swap space, execute  

                    grep SwapTotal     /proc/meminfo

-           To check the space in  /tmp directory, execute

                    df –h /tmp

		Changes to be made to Kernel parameters   If you have not used the "oracle-validated" package to perform all prerequisites. You will need to manually perform the following setup tasks :   Oracle recommend the following minimum parameter settings : shmmax 2147483648 shmmni 4096 shmall 2097152 shmmin 1 semmsl 250 semmns 32000 semopm 100 semmni 128 file-max 65536 ip_local_port_range 1024   65000 rmem_default 1048576 rmem_max 1048576 wmem_default 262144 wmem_max 262144 We do all these changes in the /etc/sysctl.conf file by adding these lines to that file: kernel.shmmax = 2147483648 kernel.shmall = 2097152 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=1048576 net.core.rmem_max=1048576 net.core.wmem_default=262144 net.core.wmem_max=262144 After appending those lines we save that file and run the following command to  make these changes effective immediately in the running system /sbin/sysctl –p Setting Shell limits for the Oracle User  To improve the performance of the software on Linux systems, you must increase the  following shell limits for the oracle user: 1. Add the following lines to /etc/security/limits.conf file oracle              soft    nproc   2047 oracle              hard    nproc   16384 oracle              soft    nofile  1024 oracle              hard    nofile  65536 2. Add the following lines to /etc/pam.d/login file session    required     /lib/security/pam_limits.so session    required     pam_limits.so 3. In order to use Oracle Software, we need to make a change in “oracle” user’s   buffer size and number of opened file descriptors. In order to do it, we add below lines  to /etc/profile file if [ $USER = "oracle" ]; then         if [ $SHELL = "/bin/ksh" ]; then               ulimit -p 16384               ulimit -n 65536         else               ulimit -u 16384 -n 65536         fi fi Installing Oracle Database 11g Release 2   Download Oracle Software OTN : Oracle Database 11g Release 2 (11.2.0.1) Software (64 -bit)   # 11.2.0.1 unzip linux.x64_11gR2_database_1of2.zip unzip linux.x64_11gR2_database_2of2.zip You should now have a single directory called "database" containing installation files.  Hosts File The "/etc/hosts" file must contain a fully qualified name for the server. <IP-address>  <fully-qualified-machine-name>  <machine-name> For example. 127.0.0.1       localhost.localdomain  localhost 10.10.9.3       pankaj-oraserver    ol5-11gr2 $uname –n  -- > to check machine name $dnsdomainname -- > to check the localdomain Install the following packages if they are not already present. binutils-2.* compat-libstdc++-33* compat-libstdc++-33*.i386.rpm elfutils-libelf* gcc-4.* gcc-c++-4.* glibc-2.* glibc-common-2.* glibc-devel-2.* glibc-headers-2.* ksh* libaio-0.* libaio-devel-0.* libgomp-4.* libgcc-4.* libstdc++-4.* libstdc++-devel-4.* make-3.* sysstat-7.* unixODBC-2.* unixODBC-devel-2.* numactl-devel-* Install all the packages required for oracle. We need to install the mentioned rpm manually. To check whether the package is installed or not rpm -qa | grep -i compact* If the package is not installed, install it with command rpm -ivh compat-db-4.2.52-5.1.i386.rpm Create groups and user for Oracle Installation In this step, we create “oinstall” and “dba” groups and “oracle” user to install Oracle Software, and groupadd  oinstall groupadd  dba groupadd oper groupadd admadmin Add oracle user and assign oinstall as primary group and others as secondary useradd -m -g oinstall -G dba,oper,asmadmin,oracle passwd oracle  AdditionalSetup The following setup tasks must be performed regardless of which setup method you used previously. Disable secure linux by editing the "/etc/selinux/config" file, making sure the SELINUX flag  is set as follows. SELINUX=disabled Alternatively, this alteration can be done using the GUI tool (Applications > System Settings  > Security Level). Click on the SELinux tab and disable the feature. If SELinux is disabled after installation, the server will need a reboot for the change to take effect. Create the directories in which the Oracle software will be installed. mkdir -p /opt/oracle/product/11.2.0/db_1 chown -R oracle:oinstall opt/ chmod -R 775 opt/ Note: /opt = ORACLE_BASE opt/oracle/product/11.2.0/db_1 =  ORACLE_HOME Login as root and issue the following command. xhost +<machine-name> $uname –n -- > to check the machnine name Login as the oracle user and add the following lines at the end of the ".bash_profile" file, remembering to adjust them for your specific installation. # Oracle Settings PATH=$PATH:$HOME/bin export PATH TMP=/tmp; export TMP TMPDIR=$TMP; export TMPDIR ORACLE_HOSTNAME=pankaj_oraserver; export ORACLE_HOSTNAME ORACLE_UNQNAME_DB11G; export ORACLE_UNQNAME ORACLE_BASE=/oracle; export ORACLE_BASE #ORACLE_HOME=@ORACLE_BASE/product/11.2.0/db_1;  export ORACLE_HOME ORACLE_HOME=/oracle/product/11.2.0/db_1/; export ORACLE_HOME ORACLE_SID=calypsotest; export ORACLE_SID PATH=/usr/sbin:$PATH; export PATH PATH=$ORACLE_HOME/bin:$PATH: export PATH LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib;  export LD_LIBRARY_PATH CLASSPATH=$ORACLE_HOME/jlib:@ORACLE_HOME/rdbms/jlib;  export CLASSPATH ./bash_profile -- To restart  bash Installation Log into the oracle user. If you are using X emulation then set the DISPLAY environmental  variable. DISPLAY=<machine-name>:0.0; export DISPLAY Start the Oracle Universal Installer (OUI) by issuing the following command in the database  directory. [oracle@pankaj-oraserver database]$ cd /home/oracle/database/ [oracle@pankaj-oraserver database]$ ls -lh total 40K drwxr-xr-x 12 root root 4.0K Apr 11 20:12 doc drwxr-xr-x  4 root root 4.0K Apr 11 20:12 install drwxr-xr-x  2 root root 4.0K Apr 11 20:12 response drwxr-xr-x  2 root root 4.0K Apr 11 20:12 rpm -rwxr-xr-x  1 root root 4.3K Apr 11 20:12 runInstaller drwxr-xr-x  2 root root 4.0K Apr 11 20:12 sshsetup drwxr-xr-x 14 root root 4.0K Apr 11 20:14 stage -rw-r--r--  1 root root 5.3K Apr 11 20:14 welcome.html sh -x runInstaller Note : If it prompted for any package installtion, please install those packages first. Installation of Oracle Database 10g completed successfully! Congratulations! Now reboot your server and login as oracle user and start newly created database.  [oracle@pankaj-oraserver ~]$ cd /oracle/product/11.2.0/db_1/ [oracle@pankaj-oraserver db_1]$ cd bin [oracle@pankaj-oraserver bin]$ sh -x dbca    Database is created successfully now. Post Installation Edit the "/etc/oratab" file setting the restart flag for each instance to "Y" calypsotest:/oracle/product/11.2.0/db_1:Y (To make your database up when your system boots) Issues I face after Installation and configuration of database [oracle@pankaj-oraserver bin]$ sqlplus SQL*Plus: Release 11.2.0.1.0 Production on Tue Apr 23 15:24:19 2013 Copyright (c) 1982, 2009, Oracle.  All rights reserved. Enter user-name: system Enter password: ERROR: ORA-01034: ORACLE not available ORA-27101: shared memory realm does not exist Linux Error: 2: No such file or directory Process ID: 0 Session ID: 0 Serial number: 0 Fix : 1-export ORACLE_SID=Your database SID My Sid is calypsotest 2-export ORACLE_HOME=YOUR ORACLE HOME for example  /oracle/product/11.2.0/db_1/ 3-export PATH=PATH:$ORACLE_HOME/bin 4-connect to sqlplus like the following: sqlplus / as sysdba 5-after connecting to sqlplus type: startup