Operating System(s):RHEL5.x, OEL5.x
How to setup cluster nodes using GNS while installing Oracle RAC 11g R2?
To set up an Oracle 11g R2 RAC installation using Oracle Grid Naming Services (GNS) the following requirements need to be met:
Table 1 describes the different interfaces, IP address settings, and the resolutions in a cluster.
Table 1. Interface Requirements
Node Virtual IP
GNS virtual IP
SCAN virtual IP
Configuring the DNS Server to support GNS
To configure changes on a DNS server for an Oracle 11g R2 cluster using GNS:
For example: gns-server IN A 18.104.22.168
where gns-server is the GNS virtual IP address given during Oracle Grid installation. The address that you provide must be routable and should be in public IP address range.
Add the following to the DNS lookup file:
clusterdomain.example.com. NS gns-server.example.com.,
where clusterdomain.example.com. is the GNS sub domain (provided during the Oracle Grid installation) that you delegate and gns-server.clustername.com. resolves to the GNS virtual IP address.
Configuring a DNS Client
To configure the changes required on the cluster nodes for name resolution:
For example, edit the /etc/resolv.conf file as:
options attempts: 2
options timeout: 1
For example, hosts: dns files nis
Once the appropriate changes have been made run the following command to restart the service:
/sbin/service nscd restart
Once done with configuring the DNS server client, during the Oracle Grid installation provide the necessary information in the Oracle Universal Interface (OUI) to proceed with the installation.