Oracle RAC Linux Network Configuration

Perform the following network configuration on all nodes in the cluster!

Introduction to Network Settings

During the Linux O/S install you already configured the IP address and host name for each of the nodes. You now need to configure the /etc/hosts file as well as adjust several of the network settings for the interconnect. I also include instructions for enabling Telnet and FTP services.

Each node should have one static IP address for the public network and one static IP address for the private cluster interconnect. The private interconnect should only be used by Oracle to transfer Cluster Manager and Cache Fusion related data. Although it is possible to use the public network for the interconnect, this is not recommended as it may cause degraded database performance (reducing the amount of bandwidth for Cache Fusion and Cluster Manager traffic). For a production RAC implementation, the interconnect should be at least gigabit or more and only be used by Oracle.

Configuring Public and Private Network

In our two-node example, you need to configure the network on both nodes for access to the public network as well as their private interconnect.

The easiest way to configure network settings in RHEL4 is with the Network Configuration program. This application can be started from the command-line as the root user account as follows:

# su -
# /usr/bin/system-config-network &

Do not use DHCP naming for the public IP address or the interconnects; you need static IP addresses!

Using the Network Configuration application, you need to configure both NIC devices as well as the /etc/hosts file. Both of these tasks can be completed using the Network Configuration GUI. Notice that the /etc/hosts settings are the same for both nodes.

Our example configuration will use the following settings:

Server 1 (linux1)
Device	IP Address	Subnet	Purpose
eth0	192.168.1.100	255.255.255.0	Connects linux1 to the public network
eth1	192.168.2.100	255.255.255.0	Connects linux1 (interconnect) to linux2 (int-linux2)
/etc/hosts
127.0.0.1 localhost loopback # Public Network - (eth0) 192.168.1.100 linux1 192.168.1.101 linux2 # Private Interconnect - (eth1) 192.168.2.100 int-linux1 192.168.2.101 int-linux2 # Public Virtual IP (VIP) addresses for - (eth0) 192.168.1.200 vip-linux1 192.168.1.201 vip-linux2

Server 2 (linux2)
Device	IP Address	Subnet	Purpose
eth0	192.168.1.101	255.255.255.0	Connects linux2 to the public network
eth1	192.168.2.101	255.255.255.0	Connects linux2 (interconnect) to linux1 (int-linux1)
/etc/hosts
127.0.0.1 localhost loopback # Public Network - (eth0) 192.168.1.100 linux1 192.168.1.101 linux2 # Private Interconnect - (eth1) 192.168.2.100 int-linux1 192.168.2.101 int-linux2 # Public Virtual IP (VIP) addresses for - (eth0) 192.168.1.200 vip-linux1 192.168.1.201 vip-linux2

Note that the virtual IP addresses only need to be defined in the /etc/hosts file (or your DNS) for both nodes. The public virtual IP addresses will be configured automatically by Oracle when you run the Oracle Universal Installer, which starts Oracle's Virtual Internet Protocol Configuration Assistant (VIPCA). All virtual IP addresses will be activated when the srvctl start nodeapps -n command is run. This is the Host Name/IP Address that will be configured in the client(s) tnsnames.ora file.