3.1.3. Enabling NAT Routing on the LVS Routers

3.1.3. Enabling NAT Routing on the LVS Routers

In a simple NAT LVS cluster where each clustered service uses only one port, like HTTP on port 80, the administrator needs only to enable packet forwarding on the LVS routers for the requests to be properly routed between the outside world and the real servers. See Section 2.5, “Turning on Packet Forwarding” for instructions on turning on packet forwarding. However, more configuration is necessary when the clustered services require more than one port to go to the same real server during a user session. For information on creating multi-port services using firewall marks, see Section 3.4, “Multi-port Services and LVS Clustering”.

Once forwarding is enabled on the LVS routers and the real servers are set up and have the clustered services running, use the Piranha Configuration Tool to configure the cluster as shown in Chapter 4, Configuring the LVS Routers with Piranha Configuration Tool.


Do not configure the floating IP for eth0:1 or eth1:1 by manually editing network scripts or using a network configuration tool. Instead, use the Piranha Configuration Tool as shown in Section 4.4, “GLOBAL SETTINGS” and Section 4.6.1, “The VIRTUAL SERVER Subsection” to configure any cluster-related virtual interfaces.

When finished, start the pulse service as shown in Section 4.8, “Starting the Cluster”. Once pulse is up and running, the active LVS router will begin routing requests to the pool of real servers.

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