Routing On The Real Servers - Red Hat ENTERPRISE LINUX 5 - VIRTUAL SERVER ADMINISTRATION Manual

Chapter 3. Setting Up LVS
BOOTPROTO=static
ONBOOT=yes
IPADDR=192.168.26.9
NETMASK=255.255.255.0
GATEWAY=192.168.26.254
The /etc/sysconfig/network-scripts/ifcfg-eth1 for the private NAT interface on the LVS
router could look something like this:
DEVICE=eth1
BOOTPROTO=static
ONBOOT=yes
IPADDR=10.11.12.9
NETMASK=255.255.255.0
In this example, the VIP for the LVS router's public interface will be 192.168.26.10 and the VIP for the
NAT or private interface will be 10.11.12.10. So, it is essential that the real servers route requests back
to the VIP for the NAT interface.
Important
The sample Ethernet interface configuration settings in this section are for the real IP
addresses of an LVS router and not the floating IP addresses. To configure the public and
private floating IP addresses the administrator should use the Piranha Configuration
Tool, as shown in
SERVER Subsection".
After configuring the primary LVS router node's network interfaces, configure the backup LVS router's
real network interfaces — taking care that none of the IP address conflict with any other IP addresses
on the network.
Important
Be sure each interface on the backup node services the same network as the interface on
primary node. For instance, if eth0 connects to the public network on the primary node, it
must also connect to the public network on the backup node as well.

3.1.2. Routing on the Real Servers

The most important thing to remember when configuring the real servers network interfaces in a NAT
topology is to set the gateway for the NAT floating IP address of the LVS router. In this example, that
address is 10.11.12.10.
Note
Once the network interfaces are up on the real servers, the machines will be unable to
ping or connect in other ways to the public network. This is normal. You will, however, be
able to ping the real IP for the LVS router's private interface, in this case 10.11.12.8.
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Section 4.4, "GLOBAL SETTINGS" Section 4.6.1, "The VIRTUAL
and