1. Preliminary Installation
This section lists the setup necessary before starting the Grid
Infrastructure software installation.
Software and Hardware requirements
Review the software and hardware requirements listed here.
Like in previous versions, the installer does a prerequisite checks before the
software installation. New in 11g Release 2 is the installer now offers the
ability to generate a Fixup script to fix kernel parameters.
SCAN (Single Client Access Name)
SCAN is new in Oracle 11g Release 2. It simplifies client
management by providing a single point of access for clients to connect to any
database in the cluster. In the event when nodes were added or removed from the
cluster, clients that use SCAN to access the cluster do not have to make any
explicit changes to the client settings. This is particularly beneficial for
RAC One Node where databases can be configured to relocate to any available
SCAN is resolvable by either of the following methods:
Name Service (DNS): At least one IP address has to be defined in DNS for the
SCAN. The recommended approach is to create a round robin SCAN resolvable to a
maximum of three different addresses for high availability and scalability.
Naming Service (GNS): Three IP addresses are automatically acquired from the
DHCP service and the GNS provides name resolution for the SCAN.
SCAN addresses, virtual IP addresses, and public IP addresses
must all be on the same subnet.
Refer to the following whitepaper
for additional information on SCAN.
In this installment, we will use GNS to resolve the SCAN
Configure GNS (Grid Naming Service) Virtual IP Address
The Grid Naming Service (GNS) is a part of the Grid Plug and Play
feature (GPnP), which allows the Oracle Clusterware to dynamically allocate
virtual IP addresses for each node through DHCP service running on the public
network. All name resolution requests for the cluster within a subdomain
delegated by the DNS are handed off to GNS using multicast Domain Name Service
(mDNS) included within the Oracle Clusterware. Using GNS eliminates the need
for managing IP addresses and name resolution and is especially advantageous in
a dynamic cluster environment where nodes are often added or removed.
Prior to the Grid Infrastructure software installation, we have
configured a static IP address for the GNS virtual IP and defined
gurnard.vcconsult.com as the subdomain to delegate in DNS.
Refer to the Oracle
Grid Infrastructure Installation Guide for additional information about
Configure Oracle ASM (Automatic Storage Management) shared storage
In our environment, we have created four ASM disks; three of
which were dedicated for storing the OCR, Voting disk, datafiles and online
redo logs and one for the Fast Recovery Area.
[root@gurnard1 ~]# oracleasm listdisks
[root@gurnard2 ~]# oracleasm listdisks
ASM storage configuration is described here.
CTSS (Cluster Time Synchronization Service)
CTSS is configured automatically as a part of the Grid
Infrastructure installation to synchronize the clocks on all the nodes. As an
alternative, you can manually configure NTP (Network Time Protocol) on both
nodes. We will synchronize the time across the cluster nodes using CTSS.
2. Install Oracle Database 11g Release 2 Grid Infrastructure software
The Grid Infrastructure software now installs both the Oracle
Clusterware and ASM into the same Oracle Home. We will use the grid Unix
account to install the software.
Download and unzip the software to a staging area and as the grid
user on gurnard1, execute runInstaller to start the installation.
uid=1100(grid) gid=1000(oinstall) groups=1000(oinstall),1100(asmadmin),1300(asmdba)
grid@gurnard1-> more .profile
Select Installation Option: Click
on Install and Configure Grid Infrastructure for a Cluster.
Select Installation Type: Click on
Select Product Languages: Select English.
Grid Plug and Play Information:
Cluster Name: gurnard-cluster
SCAN Name: gurnard-cluster-scan.gurnard.vcconsult.com
SCAN Port: 1521
Select Configure GNS.
GNS Sub Domain: gurnard.vcconsult.com
GNS VIP Address: 192.168.1.208
Cluster Node Information:
Click on Add.
Virtual IP Name: AUTO
Click on SSH Connectivity.
OS Username: grid
OS Password: ******
Click on Setup.
Click on OK.
Specify Network Interface Usage:
Interface Name: eth0;
Subnet: 192.168.1.0; Interface Type: Public
Interface Name: eth1;
Subnet: 10.10.10.0; Interface Type: Private
Storage Option Information: Select
Automatic Storage Management (ASM).
Create ASM Disk Group:
Disk Group Name: DATA
Redundancy: Select Normal
Add Disks: Select Candidate
Select ORCL:VOL1, ORCL:VOL2,
Clusterware files are stored in the DATA disk group. The disk group redundancy
level determines the type of default file mirroring by Oracle ASM:
External redundancy: no mirroring
Normal redundancy: 2-way mirroring
High redundancy: 3-way mirroring