Installation guide

104 Chapter 9. Setting Up a Red Hat Enterprise Linux LVS Cluster

ration Tool. In particular, FTP services and the use of ﬁrewall marks requires extra

manual conﬁguration of the LVS routers to route requests properly.

9.1.1. Conﬁguring Network Interfaces for a NAT LVS Cluster

To set up a NAT LVS cluster, the administrator must ﬁrst conﬁgure the network interfaces

for the public network and the private network on the LVS routers. In this example, the LVS

routers’ public interfaces (eth0) will be on the 192.168.26/24 network (I know, I know,

this is not a routable IP, but let us pretend there is a ﬁrewall in front of the LVS router for

good measure) and the private interfaces which link to the real servers (eth1) will be on

the 10.11.12/24 network.

So on the active or primary LVS router node, the public interface’s network script,

/etc/sysconfig/network-scripts/ifcfg-eth0, could look something like this:

DEVICE=eth0

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 Section 10.4 GLOBAL SETTINGS and

Section 10.6.1 The VIRTUAL SERVER Subsection.